mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/herbert/cryptodev-2.6.git
synced 2026-04-18 03:23:53 -04:00
5cf06ea56ee67209d4e9a0b381641fb062ecd2c3
81 Commits
| Author | SHA1 | Message | Date | |
|---|---|---|---|---|
Lorenzo Stoakes
|
5dba5cc2e0 |
mm: introduce VM_MAYBE_GUARD and make visible in /proc/$pid/smaps
Patch series "introduce VM_MAYBE_GUARD and make it sticky", v4. Currently, guard regions are not visible to users except through /proc/$pid/pagemap, with no explicit visibility at the VMA level. This makes the feature less useful, as it isn't entirely apparent which VMAs may have these entries present, especially when performing actions which walk through memory regions such as those performed by CRIU. This series addresses this issue by introducing the VM_MAYBE_GUARD flag which fulfils this role, updating the smaps logic to display an entry for these. The semantics of this flag are that a guard region MAY be present if set (we cannot be sure, as we can't efficiently track whether an MADV_GUARD_REMOVE finally removes all the guard regions in a VMA) - but if not set the VMA definitely does NOT have any guard regions present. It's problematic to establish this flag without further action, because that means that VMAs with guard regions in them become non-mergeable with adjacent VMAs for no especially good reason. To work around this, this series also introduces the concept of 'sticky' VMA flags - that is flags which: a. if set in one VMA and not in another still permit those VMAs to be merged (if otherwise compatible). b. When they are merged, the resultant VMA must have the flag set. The VMA logic is updated to propagate these flags correctly. Additionally, VM_MAYBE_GUARD being an explicit VMA flag allows us to solve an issue with file-backed guard regions - previously these established an anon_vma object for file-backed mappings solely to have vma_needs_copy() correctly propagate guard region mappings to child processes. We introduce a new flag alias VM_COPY_ON_FORK (which currently only specifies VM_MAYBE_GUARD) and update vma_needs_copy() to check explicitly for this flag and to copy page tables if it is present, which resolves this issue. Additionally, we add the ability for allow-listed VMA flags to be atomically writable with only mmap/VMA read locks held. The only flag we allow so far is VM_MAYBE_GUARD, which we carefully ensure does not cause any races by being allowed to do so. This allows us to maintain guard region installation as a read-locked operation and not endure the overhead of obtaining a write lock here. Finally we introduce extensive VMA userland tests to assert that the sticky VMA logic behaves correctly as well as guard region self tests to assert that smaps visibility is correctly implemented. This patch (of 9): Currently, if a user needs to determine if guard regions are present in a range, they have to scan all VMAs (or have knowledge of which ones might have guard regions). Since commit |
||
|
Linus Torvalds
|
55a42f78ff |
Merge tag 'vfio-v6.18-rc1' of https://github.com/awilliam/linux-vfio
Pull VFIO updates from Alex Williamson:
- Use fdinfo to expose the sysfs path of a device represented by a vfio
device file (Alex Mastro)
- Mark vfio-fsl-mc, vfio-amba, and the reset functions for
vfio-platform for removal as these are either orphaned or believed to
be unused (Alex Williamson)
- Add reviewers for vfio-platform to save it from also being marked for
removal (Mostafa Saleh, Pranjal Shrivastava)
- VFIO selftests, including basic sanity testing and minimal userspace
drivers for testing against real hardware. This is also expected to
provide integration with KVM selftests for KVM-VFIO interfaces (David
Matlack, Josh Hilke)
- Fix drivers/cdx and vfio/cdx to build without CONFIG_GENERIC_MSI_IRQ
(Nipun Gupta)
- Fix reference leak in hisi_acc (Miaoqian Lin)
- Use consistent return for unsupported device feature (Alex Mastro)
- Unwind using the correct memory free callback in vfio/pds (Zilin
Guan)
- Use IRQ_DISABLE_LAZY flag to improve handling of pre-PCI2.3 INTx and
resolve stalled interrupt on ppc64 (Timothy Pearson)
- Enable GB300 in nvgrace-gpu vfio-pci variant driver (Tushar Dave)
- Misc:
- Drop unnecessary ternary conversion in vfio/pci (Xichao Zhao)
- Grammatical fix in nvgrace-gpu (Morduan Zang)
- Update Shameer's email address (Shameer Kolothum)
- Fix document build warning (Alex Williamson)
* tag 'vfio-v6.18-rc1' of https://github.com/awilliam/linux-vfio: (48 commits)
vfio/nvgrace-gpu: Add GB300 SKU to the devid table
vfio/pci: Fix INTx handling on legacy non-PCI 2.3 devices
vfio/pds: replace bitmap_free with vfree
vfio: return -ENOTTY for unsupported device feature
hisi_acc_vfio_pci: Fix reference leak in hisi_acc_vfio_debug_init
vfio/platform: Mark reset drivers for removal
vfio/amba: Mark for removal
MAINTAINERS: Add myself as VFIO-platform reviewer
MAINTAINERS: Add myself as VFIO-platform reviewer
docs: proc.rst: Fix VFIO Device title formatting
vfio: selftests: Fix .gitignore for already tracked files
vfio/cdx: update driver to build without CONFIG_GENERIC_MSI_IRQ
cdx: don't select CONFIG_GENERIC_MSI_IRQ
MAINTAINERS: Update Shameer Kolothum's email address
vfio: selftests: Add a script to help with running VFIO selftests
vfio: selftests: Make iommufd the default iommu_mode
vfio: selftests: Add iommufd mode
vfio: selftests: Add iommufd_compat_type1{,v2} modes
vfio: selftests: Add vfio_type1v2_mode
vfio: selftests: Replicate tests across all iommu_modes
...
|
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Linus Torvalds
|
ee2fe81cdc |
Merge tag 'docs-6.18' of git://git.lwn.net/linux
Pull documentation updates from Jonathan Corbet:
"It has been a relatively busy cycle in docsland, with changes all
over:
- Bring the kernel memory-model docs into the Sphinx build in the
"literal include" mode.
- Lots of build-infrastructure work, further cleaning up long-term
kernel-doc technical debt. The sphinx-pre-install tool has been
converted to Python and updated for current systems.
- A new tool to detect when documents have been moved and generate
HTML redirects; this can be used on kernel.org (or any other site
hosting the rendered docs) to avoid breaking links.
- Automated processing of the YAML files describing the netlink
protocol.
- A significant update of the maintainer's PGP guide.
... and a seemingly endless series of typo fixes, build-problem fixes,
etc"
* tag 'docs-6.18' of git://git.lwn.net/linux: (193 commits)
Documentation/features: Update feature lists for 6.17-rc7
docs: remove cdomain.py
Documentation/process: submitting-patches: fix typo in "were do"
docs: dev-tools/lkmm: Fix typo of missing file extension
Documentation: trace: histogram: Convert ftrace docs cross-reference
Documentation: trace: histogram-design: Wrap introductory note in note:: directive
Documentation: trace: historgram-design: Separate sched_waking histogram section heading and the following diagram
Documentation: trace: histogram-design: Trim trailing vertices in diagram explanation text
Documentation: trace: histogram: Fix histogram trigger subsection number order
docs: driver-api: fix spelling of "buses".
Documentation: fbcon: Use admonition directives
Documentation: fbcon: Reindent 8th step of attach/detach/unload
Documentation: fbcon: Add boot options and attach/detach/unload section headings
docs: filesystems: sysfs: add remaining top level sysfs directory descriptions
docs: filesystems: sysfs: clarify symlink destinations in dev and bus/devices descriptions
docs: filesystems: sysfs: remove top level sysfs net directory
docs: maintainer: Fix ambiguous subheading formatting
docs: kdoc: a few more dump_typedef() tweaks
docs: kdoc: remove redundant comment stripping in dump_typedef()
docs: kdoc: remove some dead code in dump_typedef()
...
|
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Linus Torvalds
|
8804d970fa |
Merge tag 'mm-stable-2025-10-01-19-00' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull MM updates from Andrew Morton:
- "mm, swap: improve cluster scan strategy" from Kairui Song improves
performance and reduces the failure rate of swap cluster allocation
- "support large align and nid in Rust allocators" from Vitaly Wool
permits Rust allocators to set NUMA node and large alignment when
perforning slub and vmalloc reallocs
- "mm/damon/vaddr: support stat-purpose DAMOS" from Yueyang Pan extend
DAMOS_STAT's handling of the DAMON operations sets for virtual
address spaces for ops-level DAMOS filters
- "execute PROCMAP_QUERY ioctl under per-vma lock" from Suren
Baghdasaryan reduces mmap_lock contention during reads of
/proc/pid/maps
- "mm/mincore: minor clean up for swap cache checking" from Kairui Song
performs some cleanup in the swap code
- "mm: vm_normal_page*() improvements" from David Hildenbrand provides
code cleanup in the pagemap code
- "add persistent huge zero folio support" from Pankaj Raghav provides
a block layer speedup by optionalls making the
huge_zero_pagepersistent, instead of releasing it when its refcount
falls to zero
- "kho: fixes and cleanups" from Mike Rapoport adds a few touchups to
the recently added Kexec Handover feature
- "mm: make mm->flags a bitmap and 64-bit on all arches" from Lorenzo
Stoakes turns mm_struct.flags into a bitmap. To end the constant
struggle with space shortage on 32-bit conflicting with 64-bit's
needs
- "mm/swapfile.c and swap.h cleanup" from Chris Li cleans up some swap
code
- "selftests/mm: Fix false positives and skip unsupported tests" from
Donet Tom fixes a few things in our selftests code
- "prctl: extend PR_SET_THP_DISABLE to only provide THPs when advised"
from David Hildenbrand "allows individual processes to opt-out of
THP=always into THP=madvise, without affecting other workloads on the
system".
It's a long story - the [1/N] changelog spells out the considerations
- "Add and use memdesc_flags_t" from Matthew Wilcox gets us started on
the memdesc project. Please see
https://kernelnewbies.org/MatthewWilcox/Memdescs and
https://blogs.oracle.com/linux/post/introducing-memdesc
- "Tiny optimization for large read operations" from Chi Zhiling
improves the efficiency of the pagecache read path
- "Better split_huge_page_test result check" from Zi Yan improves our
folio splitting selftest code
- "test that rmap behaves as expected" from Wei Yang adds some rmap
selftests
- "remove write_cache_pages()" from Christoph Hellwig removes that
function and converts its two remaining callers
- "selftests/mm: uffd-stress fixes" from Dev Jain fixes some UFFD
selftests issues
- "introduce kernel file mapped folios" from Boris Burkov introduces
the concept of "kernel file pages". Using these permits btrfs to
account its metadata pages to the root cgroup, rather than to the
cgroups of random inappropriate tasks
- "mm/pageblock: improve readability of some pageblock handling" from
Wei Yang provides some readability improvements to the page allocator
code
- "mm/damon: support ARM32 with LPAE" from SeongJae Park teaches DAMON
to understand arm32 highmem
- "tools: testing: Use existing atomic.h for vma/maple tests" from
Brendan Jackman performs some code cleanups and deduplication under
tools/testing/
- "maple_tree: Fix testing for 32bit compiles" from Liam Howlett fixes
a couple of 32-bit issues in tools/testing/radix-tree.c
- "kasan: unify kasan_enabled() and remove arch-specific
implementations" from Sabyrzhan Tasbolatov moves KASAN arch-specific
initialization code into a common arch-neutral implementation
- "mm: remove zpool" from Johannes Weiner removes zspool - an
indirection layer which now only redirects to a single thing
(zsmalloc)
- "mm: task_stack: Stack handling cleanups" from Pasha Tatashin makes a
couple of cleanups in the fork code
- "mm: remove nth_page()" from David Hildenbrand makes rather a lot of
adjustments at various nth_page() callsites, eventually permitting
the removal of that undesirable helper function
- "introduce kasan.write_only option in hw-tags" from Yeoreum Yun
creates a KASAN read-only mode for ARM, using that architecture's
memory tagging feature. It is felt that a read-only mode KASAN is
suitable for use in production systems rather than debug-only
- "mm: hugetlb: cleanup hugetlb folio allocation" from Kefeng Wang does
some tidying in the hugetlb folio allocation code
- "mm: establish const-correctness for pointer parameters" from Max
Kellermann makes quite a number of the MM API functions more accurate
about the constness of their arguments. This was getting in the way
of subsystems (in this case CEPH) when they attempt to improving
their own const/non-const accuracy
- "Cleanup free_pages() misuse" from Vishal Moola fixes a number of
code sites which were confused over when to use free_pages() vs
__free_pages()
- "Add Rust abstraction for Maple Trees" from Alice Ryhl makes the
mapletree code accessible to Rust. Required by nouveau and by its
forthcoming successor: the new Rust Nova driver
- "selftests/mm: split_huge_page_test: split_pte_mapped_thp
improvements" from David Hildenbrand adds a fix and some cleanups to
the thp selftesting code
- "mm, swap: introduce swap table as swap cache (phase I)" from Chris
Li and Kairui Song is the first step along the path to implementing
"swap tables" - a new approach to swap allocation and state tracking
which is expected to yield speed and space improvements. This
patchset itself yields a 5-20% performance benefit in some situations
- "Some ptdesc cleanups" from Matthew Wilcox utilizes the new memdesc
layer to clean up the ptdesc code a little
- "Fix va_high_addr_switch.sh test failure" from Chunyu Hu fixes some
issues in our 5-level pagetable selftesting code
- "Minor fixes for memory allocation profiling" from Suren Baghdasaryan
addresses a couple of minor issues in relatively new memory
allocation profiling feature
- "Small cleanups" from Matthew Wilcox has a few cleanups in
preparation for more memdesc work
- "mm/damon: add addr_unit for DAMON_LRU_SORT and DAMON_RECLAIM" from
Quanmin Yan makes some changes to DAMON in furtherance of supporting
arm highmem
- "selftests/mm: Add -Wunreachable-code and fix warnings" from Muhammad
Anjum adds that compiler check to selftests code and fixes the
fallout, by removing dead code
- "Improvements to Victim Process Thawing and OOM Reaper Traversal
Order" from zhongjinji makes a number of improvements in the OOM
killer: mainly thawing a more appropriate group of victim threads so
they can release resources
- "mm/damon: misc fixups and improvements for 6.18" from SeongJae Park
is a bunch of small and unrelated fixups for DAMON
- "mm/damon: define and use DAMON initialization check function" from
SeongJae Park implement reliability and maintainability improvements
to a recently-added bug fix
- "mm/damon/stat: expose auto-tuned intervals and non-idle ages" from
SeongJae Park provides additional transparency to userspace clients
of the DAMON_STAT information
- "Expand scope of khugepaged anonymous collapse" from Dev Jain removes
some constraints on khubepaged's collapsing of anon VMAs. It also
increases the success rate of MADV_COLLAPSE against an anon vma
- "mm: do not assume file == vma->vm_file in compat_vma_mmap_prepare()"
from Lorenzo Stoakes moves us further towards removal of
file_operations.mmap(). This patchset concentrates upon clearing up
the treatment of stacked filesystems
- "mm: Improve mlock tracking for large folios" from Kiryl Shutsemau
provides some fixes and improvements to mlock's tracking of large
folios. /proc/meminfo's "Mlocked" field became more accurate
- "mm/ksm: Fix incorrect accounting of KSM counters during fork" from
Donet Tom fixes several user-visible KSM stats inaccuracies across
forks and adds selftest code to verify these counters
- "mm_slot: fix the usage of mm_slot_entry" from Wei Yang addresses
some potential but presently benign issues in KSM's mm_slot handling
* tag 'mm-stable-2025-10-01-19-00' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (372 commits)
mm: swap: check for stable address space before operating on the VMA
mm: convert folio_page() back to a macro
mm/khugepaged: use start_addr/addr for improved readability
hugetlbfs: skip VMAs without shareable locks in hugetlb_vmdelete_list
alloc_tag: fix boot failure due to NULL pointer dereference
mm: silence data-race in update_hiwater_rss
mm/memory-failure: don't select MEMORY_ISOLATION
mm/khugepaged: remove definition of struct khugepaged_mm_slot
mm/ksm: get mm_slot by mm_slot_entry() when slot is !NULL
hugetlb: increase number of reserving hugepages via cmdline
selftests/mm: add fork inheritance test for ksm_merging_pages counter
mm/ksm: fix incorrect KSM counter handling in mm_struct during fork
drivers/base/node: fix double free in register_one_node()
mm: remove PMD alignment constraint in execmem_vmalloc()
mm/memory_hotplug: fix typo 'esecially' -> 'especially'
mm/rmap: improve mlock tracking for large folios
mm/filemap: map entire large folio faultaround
mm/fault: try to map the entire file folio in finish_fault()
mm/rmap: mlock large folios in try_to_unmap_one()
mm/rmap: fix a mlock race condition in folio_referenced_one()
...
|
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Suren Baghdasaryan
|
b9e2f58ffb |
alloc_tag: mark inaccurate allocation counters in /proc/allocinfo output
While rare, memory allocation profiling can contain inaccurate counters if
slab object extension vector allocation fails. That allocation might
succeed later but prior to that, slab allocations that would have used
that object extension vector will not be accounted for. To indicate
incorrect counters, "accurate:no" marker is appended to the call site line
in the /proc/allocinfo output. Bump up /proc/allocinfo version to reflect
the change in the file format and update documentation.
Example output with invalid counters:
allocinfo - version: 2.0
0 0 arch/x86/kernel/kdebugfs.c:105 func:create_setup_data_nodes
0 0 arch/x86/kernel/alternative.c:2090 func:alternatives_smp_module_add
0 0 arch/x86/kernel/alternative.c:127 func:__its_alloc accurate:no
0 0 arch/x86/kernel/fpu/regset.c:160 func:xstateregs_set
0 0 arch/x86/kernel/fpu/xstate.c:1590 func:fpstate_realloc
0 0 arch/x86/kernel/cpu/aperfmperf.c:379 func:arch_enable_hybrid_capacity_scale
0 0 arch/x86/kernel/cpu/amd_cache_disable.c:258 func:init_amd_l3_attrs
49152 48 arch/x86/kernel/cpu/mce/core.c:2709 func:mce_device_create accurate:no
32768 1 arch/x86/kernel/cpu/mce/genpool.c:132 func:mce_gen_pool_create
0 0 arch/x86/kernel/cpu/mce/amd.c:1341 func:mce_threshold_create_device
[surenb@google.com: document new "accurate:no" marker]
Fixes: 39d117e04d15 ("alloc_tag: mark inaccurate allocation counters in /proc/allocinfo output")
[akpm@linux-foundation.org: simplification per Usama, reflow text]
[akpm@linux-foundation.org: add newline to prevent docs warning, per Randy]
Link: https://lkml.kernel.org/r/20250915230224.4115531-1-surenb@google.com
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Suggested-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Acked-by: Usama Arif <usamaarif642@gmail.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: David Rientjes <rientjes@google.com>
Cc: David Wang <00107082@163.com>
Cc: Kent Overstreet <kent.overstreet@linux.dev>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Sourav Panda <souravpanda@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
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David Hildenbrand
|
9dc21bbd62 |
prctl: extend PR_SET_THP_DISABLE to optionally exclude VM_HUGEPAGE
Patch series "prctl: extend PR_SET_THP_DISABLE to only provide THPs when
advised", v5.
This will allow individual processes to opt-out of THP = "always" into THP
= "madvise", without affecting other workloads on the system. This has
been extensively discussed on the mailing list and has been summarized
very well by David in the first patch which also includes the links to
alternatives, please refer to the first patch commit message for the
motivation for this series.
Patch 1 adds the PR_THP_DISABLE_EXCEPT_ADVISED flag to implement this,
along with the MMF changes.
Patch 2 is a cleanup patch for tva_flags that will allow the forced
collapse case to be transmitted to vma_thp_disabled (which is done in
patch 3).
Patch 4 adds documentation for PR_SET_THP_DISABLE/PR_GET_THP_DISABLE.
Patches 6-7 implement the selftests for PR_SET_THP_DISABLE for completely
disabling THPs (old behaviour) and only enabling it at advise
(PR_THP_DISABLE_EXCEPT_ADVISED).
This patch (of 7):
People want to make use of more THPs, for example, moving from the "never"
system policy to "madvise", or from "madvise" to "always".
While this is great news for every THP desperately waiting to get
allocated out there, apparently there are some workloads that require a
bit of care during that transition: individual processes may need to
opt-out from this behavior for various reasons, and this should be
permitted without needing to make all other workloads on the system
similarly opt-out.
The following scenarios are imaginable:
(1) Switch from "none" system policy to "madvise"/"always", but keep THPs
disabled for selected workloads.
(2) Stay at "none" system policy, but enable THPs for selected
workloads, making only these workloads use the "madvise" or "always"
policy.
(3) Switch from "madvise" system policy to "always", but keep the
"madvise" policy for selected workloads: allocate THPs only when
advised.
(4) Stay at "madvise" system policy, but enable THPs even when not advised
for selected workloads -- "always" policy.
Once can emulate (2) through (1), by setting the system policy to
"madvise"/"always" while disabling THPs for all processes that don't want
THPs. It requires configuring all workloads, but that is a user-space
problem to sort out.
(4) can be emulated through (3) in a similar way.
Back when (1) was relevant in the past, as people started enabling THPs,
we added PR_SET_THP_DISABLE, so relevant workloads that were not ready yet
(i.e., used by Redis) were able to just disable THPs completely. Redis
still implements the option to use this interface to disable THPs
completely.
With PR_SET_THP_DISABLE, we added a way to force-disable THPs for a
workload -- a process, including fork+exec'ed process hierarchy. That
essentially made us support (1): simply disable THPs for all workloads
that are not ready for THPs yet, while still enabling THPs system-wide.
The quest for handling (3) and (4) started, but current approaches
(completely new prctl, options to set other policies per process,
alternatives to prctl -- mctrl, cgroup handling) don't look particularly
promising. Likely, the future will use bpf or something similar to
implement better policies, in particular to also make better decisions
about THP sizes to use, but this will certainly take a while as that work
just started.
Long story short: a simple enable/disable is not really suitable for the
future, so we're not willing to add completely new toggles.
While we could emulate (3)+(4) through (1)+(2) by simply disabling THPs
completely for these processes, this is a step backwards, because these
processes can no longer allocate THPs in regions where THPs were
explicitly advised: regions flagged as VM_HUGEPAGE. Apparently, that
imposes a problem for relevant workloads, because "not THPs" is certainly
worse than "THPs only when advised".
Could we simply relax PR_SET_THP_DISABLE, to "disable THPs unless not
explicitly advised by the app through MAD_HUGEPAGE"? *maybe*, but this
would change the documented semantics quite a bit, and the versatility to
use it for debugging purposes, so I am not 100% sure that is what we want
-- although it would certainly be much easier.
So instead, as an easy way forward for (3) and (4), add an option to
make PR_SET_THP_DISABLE disable *less* THPs for a process.
In essence, this patch:
(A) Adds PR_THP_DISABLE_EXCEPT_ADVISED, to be used as a flag in arg3
of prctl(PR_SET_THP_DISABLE) when disabling THPs (arg2 != 0).
prctl(PR_SET_THP_DISABLE, 1, PR_THP_DISABLE_EXCEPT_ADVISED).
(B) Makes prctl(PR_GET_THP_DISABLE) return 3 if
PR_THP_DISABLE_EXCEPT_ADVISED was set while disabling.
Previously, it would return 1 if THPs were disabled completely. Now
it returns the set flags as well: 3 if PR_THP_DISABLE_EXCEPT_ADVISED
was set.
(C) Renames MMF_DISABLE_THP to MMF_DISABLE_THP_COMPLETELY, to express
the semantics clearly.
Fortunately, there are only two instances outside of prctl() code.
(D) Adds MMF_DISABLE_THP_EXCEPT_ADVISED to express "no THP except for VMAs
with VM_HUGEPAGE" -- essentially "thp=madvise" behavior
Fortunately, we only have to extend vma_thp_disabled().
(E) Indicates "THP_enabled: 0" in /proc/pid/status only if THPs are
disabled completely
Only indicating that THPs are disabled when they are really disabled
completely, not only partially.
For now, we don't add another interface to obtained whether THPs
are disabled partially (PR_THP_DISABLE_EXCEPT_ADVISED was set). If
ever required, we could add a new entry.
The documented semantics in the man page for PR_SET_THP_DISABLE "is
inherited by a child created via fork(2) and is preserved across
execve(2)" is maintained. This behavior, for example, allows for
disabling THPs for a workload through the launching process (e.g., systemd
where we fork() a helper process to then exec()).
For now, MADV_COLLAPSE will *fail* in regions without VM_HUGEPAGE and
VM_NOHUGEPAGE. As MADV_COLLAPSE is a clear advise that user space thinks
a THP is a good idea, we'll enable that separately next (requiring a bit
of cleanup first).
There is currently not way to prevent that a process will not issue
PR_SET_THP_DISABLE itself to re-enable THP. There are not really known
users for re-enabling it, and it's against the purpose of the original
interface. So if ever required, we could investigate just forbidding to
re-enable them, or make this somehow configurable.
Link: https://lkml.kernel.org/r/20250815135549.130506-1-usamaarif642@gmail.com
Link: https://lkml.kernel.org/r/20250815135549.130506-2-usamaarif642@gmail.com
Acked-by: Zi Yan <ziy@nvidia.com>
Acked-by: Usama Arif <usamaarif642@gmail.com>
Tested-by: Usama Arif <usamaarif642@gmail.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Signed-off-by: Usama Arif <usamaarif642@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Jann Horn <jannh@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Mariano Pache <npache@redhat.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: SeongJae Park <sj@kernel.org>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yafang <laoar.shao@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
||
|
Baruch Siach
|
7e5a0fe4e8 |
doc: filesystems: proc: remove stale information from intro
Most of the information in the first paragraph of the Introduction/Credits section is outdated. Documentation update suggestions should go to documentation maintainers listed in MAINTAINERS. Remove misleading contact information. Signed-off-by: Baruch Siach <baruch@tkos.co.il> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/cb4987a16ed96ee86841aec921d914bd44249d0b.1756294647.git.baruch@tkos.co.il |
||
|
Aleksa Sarai
|
fe49652e36 |
procfs: add "pidns" mount option
Since the introduction of pid namespaces, their interaction with procfs
has been entirely implicit in ways that require a lot of dancing around
by programs that need to construct sandboxes with different PID
namespaces.
Being able to explicitly specify the pid namespace to use when
constructing a procfs super block will allow programs to no longer need
to fork off a process which does then does unshare(2) / setns(2) and
forks again in order to construct a procfs in a pidns.
So, provide a "pidns" mount option which allows such users to just
explicitly state which pid namespace they want that procfs instance to
use. This interface can be used with fsconfig(2) either with a file
descriptor or a path:
fsconfig(procfd, FSCONFIG_SET_FD, "pidns", NULL, nsfd);
fsconfig(procfd, FSCONFIG_SET_STRING, "pidns", "/proc/self/ns/pid", 0);
or with classic mount(2) / mount(8):
// mount -t proc -o pidns=/proc/self/ns/pid proc /tmp/proc
mount("proc", "/tmp/proc", "proc", MS_..., "pidns=/proc/self/ns/pid");
As this new API is effectively shorthand for setns(2) followed by
mount(2), the permission model for this mirrors pidns_install() to avoid
opening up new attack surfaces by loosening the existing permission
model.
In order to avoid having to RCU-protect all users of proc_pid_ns() (to
avoid UAFs), attempting to reconfigure an existing procfs instance's pid
namespace will error out with -EBUSY. Creating new procfs instances is
quite cheap, so this should not be an impediment to most users, and lets
us avoid a lot of churn in fs/proc/* for a feature that it seems
unlikely userspace would use.
Signed-off-by: Aleksa Sarai <cyphar@cyphar.com>
Link: https://lore.kernel.org/20250805-procfs-pidns-api-v4-2-705f984940e7@cyphar.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
|
||
|
Alex Williamson
|
093458c58f |
docs: proc.rst: Fix VFIO Device title formatting
Title underline is one character too short.
Cc: Alex Mastro <amastro@fb.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Closes: https://lore.kernel.org/all/20250828123035.2f0c74e7@canb.auug.org.au
Fixes:
|
||
|
Alex Mastro
|
1e736f1489 |
vfio/pci: print vfio-device syspath to fdinfo
Print the PCI device syspath to a vfio device's fdinfo. This enables tools to query which device is associated with a given vfio device fd. This results in output like below: $ cat /proc/"$SOME_PID"/fdinfo/"$VFIO_FD" | grep vfio vfio-device-syspath: /sys/devices/pci0000:e0/0000:e0:01.1/0000:e1:00.0/0000:e2:05.0/0000:e8:00.0 Signed-off-by: Alex Mastro <amastro@fb.com> Reviewed-by: Amit Machhiwal <amachhiw@linux.ibm.com> Tested-by: Amit Machhiwal <amachhiw@linux.ibm.com> Link: https://lore.kernel.org/r/20250804-show-fdinfo-v4-1-96b14c5691b3@fb.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com> |
||
|
Vlastimil Babka
|
8356a5a3b0 |
mm, vmstat: remove the NR_WRITEBACK_TEMP node_stat_item counter
The only user of the counter (FUSE) was removed in commit
|
||
|
wangfushuai
|
1b8e4091ff |
docs: proc: update VmFlags documentation in smaps
Remove outdated VM_DENYWRITE("dw") reference and add missing
VM_LOCKONFAULT("lf") and VM_UFFD_MINOR("ui") flags.
[akpm@linux-foundation.org: add "dp" (VM_DROPPABLE), per Tal]
Link: https://lkml.kernel.org/r/20250607153614.81914-1-wangfushuai@baidu.com
Signed-off-by: wangfushuai <wangfushuai@baidu.com>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Mariano Pache <npache@redhat.com>
Cc: xu xin <xu.xin16@zte.com.cn>
Cc: Tal Zussman <tz2294@columbia.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
||
|
Linus Torvalds
|
d6b02199cd |
Merge tag 'mm-nonmm-stable-2025-03-30-18-23' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull non-MM updates from Andrew Morton: - The series "powerpc/crash: use generic crashkernel reservation" from Sourabh Jain changes powerpc's kexec code to use more of the generic layers. - The series "get_maintainer: report subsystem status separately" from Vlastimil Babka makes some long-requested improvements to the get_maintainer output. - The series "ucount: Simplify refcounting with rcuref_t" from Sebastian Siewior cleans up and optimizing the refcounting in the ucount code. - The series "reboot: support runtime configuration of emergency hw_protection action" from Ahmad Fatoum improves the ability for a driver to perform an emergency system shutdown or reboot. - The series "Converge on using secs_to_jiffies() part two" from Easwar Hariharan performs further migrations from msecs_to_jiffies() to secs_to_jiffies(). - The series "lib/interval_tree: add some test cases and cleanup" from Wei Yang permits more userspace testing of kernel library code, adds some more tests and performs some cleanups. - The series "hung_task: Dump the blocking task stacktrace" from Masami Hiramatsu arranges for the hung_task detector to dump the stack of the blocking task and not just that of the blocked task. - The series "resource: Split and use DEFINE_RES*() macros" from Andy Shevchenko provides some cleanups to the resource definition macros. - Plus the usual shower of singleton patches - please see the individual changelogs for details. * tag 'mm-nonmm-stable-2025-03-30-18-23' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (77 commits) mailmap: consolidate email addresses of Alexander Sverdlin fs/procfs: fix the comment above proc_pid_wchan() relay: use kasprintf() instead of fixed buffer formatting resource: replace open coded variant of DEFINE_RES() resource: replace open coded variants of DEFINE_RES_*_NAMED() resource: replace open coded variant of DEFINE_RES_NAMED_DESC() resource: split DEFINE_RES_NAMED_DESC() out of DEFINE_RES_NAMED() samples: add hung_task detector mutex blocking sample hung_task: show the blocker task if the task is hung on mutex kexec_core: accept unaccepted kexec segments' destination addresses watchdog/perf: optimize bytes copied and remove manual NUL-termination lib/interval_tree: fix the comment of interval_tree_span_iter_next_gap() lib/interval_tree: skip the check before go to the right subtree lib/interval_tree: add test case for span iteration lib/interval_tree: add test case for interval_tree_iter_xxx() helpers lib/rbtree: add random seed lib/rbtree: split tests lib/rbtree: enable userland test suite for rbtree related data structure checkpatch: describe --min-conf-desc-length scripts/gdb/symbols: determine KASLR offset on s390 ... |
||
|
Nico Pache
|
0bfd458685 |
MM documentation: add "Unaccepted" meminfo entry
Commit
|
||
|
Nico Pache
|
835de37603 |
meminfo: add a per node counter for balloon drivers
Patch series "track memory used by balloon drivers", v2. This series introduces a way to track memory used by balloon drivers. Add a NR_BALLOON_PAGES counter to track how many pages are reclaimed by the balloon drivers. First add the accounting, then updates the balloon drivers (virtio, Hyper-V, VMware, Pseries-cmm, and Xen) to maintain this counter. The virtio, Vmware, and pseries-cmm balloon drivers utilize the balloon_compaction interface to allocate and free balloon pages. Other balloon drivers will have to maintain this counter manually. This makes the information visible in memory reporting interfaces like /proc/meminfo, show_mem, and OOM reporting. This provides admins visibility into their VM balloon sizes without requiring different virtualization tooling. Furthermore, this information is helpful when debugging an OOM inside a VM. This patch (of 4): Add NR_BALLOON_PAGES counter to track memory used by balloon drivers and expose it through /proc/meminfo and other memory reporting interfaces. [npache@redhat.com: document Balloon Meminfo entry] Link: https://lkml.kernel.org/r/a0315ccf-f244-460e-8643-fd7388724fe5@redhat.com Link: https://lkml.kernel.org/r/20250314213757.244258-1-npache@redhat.com Link: https://lkml.kernel.org/r/20250314213757.244258-2-npache@redhat.com Signed-off-by: Nico Pache <npache@redhat.com> Cc: Alexander Atanasov <alexander.atanasov@virtuozzo.com> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: David Hildenbrand <david@redhat.com> Cc: Dexuan Cui <decui@microsoft.com> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Juegren Gross <jgross@suse.com> Cc: Kanchana P Sridhar <kanchana.p.sridhar@intel.com> Cc: K. Y. Srinivasan <kys@microsoft.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Shakeel Butt <shakeel.butt@linux.dev> Cc: Stefano Stabellini <sstabellini@kernel.org> Cc: Wei Liu <wei.liu@kernel.org> Cc: Michael Kelley <mhklinux@outlook.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
||
|
David Hildenbrand
|
749492229e |
mm: stop maintaining the per-page mapcount of large folios (CONFIG_NO_PAGE_MAPCOUNT)
Everything is in place to stop using the per-page mapcounts in large
folios: the mapcount of tail pages will always be logically 0 (-1 value),
just like it currently is for hugetlb folios already, and the page
mapcount of the head page is either 0 (-1 value) or contains a page type
(e.g., hugetlb).
Maintaining _nr_pages_mapped without per-page mapcounts is impossible, so
that one also has to go with CONFIG_NO_PAGE_MAPCOUNT.
There are two remaining implications:
(1) Per-node, per-cgroup and per-lruvec stats of "NR_ANON_MAPPED"
("mapped anonymous memory") and "NR_FILE_MAPPED"
("mapped file memory"):
As soon as any page of the folio is mapped -- folio_mapped() -- we
now account the complete folio as mapped. Once the last page is
unmapped -- !folio_mapped() -- we account the complete folio as
unmapped.
This implies that ...
* "AnonPages" and "Mapped" in /proc/meminfo and
/sys/devices/system/node/*/meminfo
* cgroup v2: "anon" and "file_mapped" in "memory.stat" and
"memory.numa_stat"
* cgroup v1: "rss" and "mapped_file" in "memory.stat" and
"memory.numa_stat
... can now appear higher than before. But note that these folios do
consume that memory, simply not all pages are actually currently
mapped.
It's worth nothing that other accounting in the kernel (esp. cgroup
charging on allocation) is not affected by this change.
[why oh why is "anon" called "rss" in cgroup v1]
(2) Detecting partial mappings
Detecting whether anon THPs are partially mapped gets a bit more
unreliable. As long as a single MM maps such a large folio
("exclusively mapped"), we can reliably detect it. Especially before
fork() / after a short-lived child process quit, we will detect
partial mappings reliably, which is the common case.
In essence, if the average per-page mapcount in an anon THP is < 1,
we know for sure that we have a partial mapping.
However, as soon as multiple MMs are involved, we might miss detecting
partial mappings: this might be relevant with long-lived child
processes. If we have a fully-mapped anon folio before fork(), once
our child processes and our parent all unmap (zap/COW) the same pages
(but not the complete folio), we might not detect the partial mapping.
However, once the child processes quit we would detect the partial
mapping.
How relevant this case is in practice remains to be seen.
Swapout/migration will likely mitigate this.
In the future, RMAP walkers could check for that for that case
(e.g., when collecting access bits during reclaim) and simply flag
them for deferred-splitting.
Link: https://lkml.kernel.org/r/20250303163014.1128035-21-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Cc: Andy Lutomirks^H^Hski <luto@kernel.org>
Cc: Borislav Betkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jann Horn <jannh@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Lance Yang <ioworker0@gmail.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Matthew Wilcow (Oracle) <willy@infradead.org>
Cc: Michal Koutn <mkoutny@suse.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: tejun heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Zefan Li <lizefan.x@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
||
|
David Hildenbrand
|
6dd55dd1c5 |
fs/proc/task_mmu: remove per-page mapcount dependency for smaps/smaps_rollup (CONFIG_NO_PAGE_MAPCOUNT)
Let's implement an alternative when per-page mapcounts in large folios are
no longer maintained -- soon with CONFIG_NO_PAGE_MAPCOUNT.
When computing the output for smaps / smaps_rollups, in particular when
calculating the USS (Unique Set Size) and the PSS (Proportional Set Size),
we still rely on per-page mapcounts.
To determine private vs. shared, we'll use folio_likely_mapped_shared(),
similar to how we handle PM_MMAP_EXCLUSIVE. Similarly, we might now
under-estimate the USS and count pages towards "shared" that are actually
"private" ("exclusively mapped").
When calculating the PSS, we'll now also use the average per-page mapcount
for large folios: this can result in both, an over-estimation and an
under-estimation of the PSS. The difference is not expected to matter
much in practice, but we'll have to learn as we go.
We can now provide folio_precise_page_mapcount() only with
CONFIG_PAGE_MAPCOUNT, and remove one of the last users of per-page
mapcounts when CONFIG_NO_PAGE_MAPCOUNT is enabled.
Document the new behavior.
Link: https://lkml.kernel.org/r/20250303163014.1128035-20-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Cc: Andy Lutomirks^H^Hski <luto@kernel.org>
Cc: Borislav Betkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jann Horn <jannh@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Lance Yang <ioworker0@gmail.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Matthew Wilcow (Oracle) <willy@infradead.org>
Cc: Michal Koutn <mkoutny@suse.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: tejun heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Zefan Li <lizefan.x@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
||
|
David Hildenbrand
|
7a34ae1449 |
fs/proc/task_mmu: remove per-page mapcount dependency for "mapmax" (CONFIG_NO_PAGE_MAPCOUNT)
Let's implement an alternative when per-page mapcounts in large folios are no longer maintained -- soon with CONFIG_NO_PAGE_MAPCOUNT. For calculating "mapmax", we now use the average per-page mapcount in a large folio instead of the per-page mapcount. For hugetlb folios and folios that are not partially mapped into MMs, there is no change. Likely, this change will not matter much in practice, and an alternative might be to simple remove this stat with CONFIG_NO_PAGE_MAPCOUNT. However, there might be value to it, so let's keep it like that and document the behavior. Link: https://lkml.kernel.org/r/20250303163014.1128035-19-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Cc: Andy Lutomirks^H^Hski <luto@kernel.org> Cc: Borislav Betkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jann Horn <jannh@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Lance Yang <ioworker0@gmail.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Matthew Wilcow (Oracle) <willy@infradead.org> Cc: Michal Koutn <mkoutny@suse.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: tejun heo <tj@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Zefan Li <lizefan.x@bytedance.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
||
|
Andrii Nakryiko
|
87ad827a27 |
docs,procfs: document /proc/PID/* access permission checks
Add a paragraph explaining what sort of capabilities a process would need to read procfs data for some other process. Also mention that reading data for its own process doesn't require any extra permissions. Link: https://lkml.kernel.org/r/20250129001747.759990-1-andrii@kernel.org Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Reviewed-by: Shakeel Butt <shakeel.butt@linux.dev> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Christian Brauner <brauner@kernel.org> Cc: Steven Rostedt (VMware) <rostedt@goodmis.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jann Horn <jannh@google.com> Cc: Kees Cook <kees@kernel.org> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: "Mike Rapoport (IBM)" <rppt@kernel.org> Cc: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Suren Baghdasaryan <surenb@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
||
|
Andrew Morton
|
91fe0e4d04 |
Documentation/filesystems/proc.rst: fix possessive form of "process"
The possessive form of "process" is "process's". Fix up various misdirected attempts at this. Also reflow some paragraphs. Cc: David Hildenbrand <david@redhat.com> Cc: Wang Yaxin <wang.yaxin@zte.com.cn> Cc: xu xin <xu.xin16@zte.com.cn> Cc: Yang Yang <yang.yang29@zte.com.cn> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
||
|
xu xin
|
3ab76c767b |
ksm: add ksm involvement information for each process
In /proc/<pid>/ksm_stat, add two extra ksm involvement items including
KSM_mergeable and KSM_merge_any. It helps administrators to better know
the system's KSM behavior at process level.
ksm_merge_any: yes/no
whether the process'mm is added by prctl() into the candidate list
of KSM or not, and fully enabled at process level.
ksm_mergeable: yes/no
whether any VMAs of the process'mm are currently applicable to KSM.
Purpose
=======
These two items are just to improve the observability of KSM at process
level, so that users can know if a certain process has enabled KSM.
For example, if without these two items, when we look at
/proc/<pid>/ksm_stat and there's no merging pages found, We are not sure
whether it is because KSM was not enabled or because KSM did not
successfully merge any pages.
Although "mg" in /proc/<pid>/smaps indicate VM_MERGEABLE, it's opaque
and not very obvious for non professionals.
[akpm@linux-foundation.org: wording tweaks, per David and akpm]
Link: https://lkml.kernel.org/r/20250110174034304QOb8eDoqtFkp3_t8mqnqc@zte.com.cn
Signed-off-by: xu xin <xu.xin16@zte.com.cn>
Acked-by: David Hildenbrand <david@redhat.com>
Tested-by: Mario Casquero <mcasquer@redhat.com>
Cc: Wang Yaxin <wang.yaxin@zte.com.cn>
Cc: Yang Yang <yang.yang29@zte.com.cn>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
|
||
|
Mark Brown
|
ae80e1629a |
mm: Define VM_SHADOW_STACK for arm64 when we support GCS
Use VM_HIGH_ARCH_5 for guarded control stack pages. Reviewed-by: Thiago Jung Bauermann <thiago.bauermann@linaro.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20241001-arm64-gcs-v13-14-222b78d87eee@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> |
||
|
Andrii Nakryiko
|
c10cb9148e |
docs/procfs: call out ioctl()-based PROCMAP_QUERY command existence
Call out PROCMAP_QUERY ioctl() existence in the section describing /proc/PID/maps file in documentation. We refer user to UAPI header for low-level details of this programmatic interface. Link: https://lkml.kernel.org/r/20240627170900.1672542-5-andrii@kernel.org Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Liam R. Howlett <Liam.Howlett@Oracle.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Christian Brauner <brauner@kernel.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Mike Rapoport (IBM) <rppt@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
||
|
Jeff Xu
|
399ab86ea5 |
/proc/pid/smaps: add mseal info for vma
Add sl in /proc/pid/smaps to indicate vma is sealed
Link: https://lkml.kernel.org/r/20240614232014.806352-2-jeffxu@google.com
Fixes:
|
||
|
Suren Baghdasaryan
|
a38568a0b4 |
lib: add version into /proc/allocinfo output
Add version string and a header at the beginning of /proc/allocinfo to
allow later format changes. Example output:
> head /proc/allocinfo
allocinfo - version: 1.0
# <size> <calls> <tag info>
0 0 init/main.c:1314 func:do_initcalls
0 0 init/do_mounts.c:353 func:mount_nodev_root
0 0 init/do_mounts.c:187 func:mount_root_generic
0 0 init/do_mounts.c:158 func:do_mount_root
0 0 init/initramfs.c:493 func:unpack_to_rootfs
0 0 init/initramfs.c:492 func:unpack_to_rootfs
0 0 init/initramfs.c:491 func:unpack_to_rootfs
512 1 arch/x86/events/rapl.c:681 func:init_rapl_pmus
128 1 arch/x86/events/rapl.c:571 func:rapl_cpu_online
[akpm@linux-foundation.org: remove stray newline from struct allocinfo_private]
Link: https://lkml.kernel.org/r/20240514163128.3662251-1-surenb@google.com
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Reviewed-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Kent Overstreet <kent.overstreet@linux.dev>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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Linus Torvalds
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61307b7be4 |
Merge tag 'mm-stable-2024-05-17-19-19' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull mm updates from Andrew Morton:
"The usual shower of singleton fixes and minor series all over MM,
documented (hopefully adequately) in the respective changelogs.
Notable series include:
- Lucas Stach has provided some page-mapping cleanup/consolidation/
maintainability work in the series "mm/treewide: Remove pXd_huge()
API".
- In the series "Allow migrate on protnone reference with
MPOL_PREFERRED_MANY policy", Donet Tom has optimized mempolicy's
MPOL_PREFERRED_MANY mode, yielding almost doubled performance in
one test.
- In their series "Memory allocation profiling" Kent Overstreet and
Suren Baghdasaryan have contributed a means of determining (via
/proc/allocinfo) whereabouts in the kernel memory is being
allocated: number of calls and amount of memory.
- Matthew Wilcox has provided the series "Various significant MM
patches" which does a number of rather unrelated things, but in
largely similar code sites.
- In his series "mm: page_alloc: freelist migratetype hygiene"
Johannes Weiner has fixed the page allocator's handling of
migratetype requests, with resulting improvements in compaction
efficiency.
- In the series "make the hugetlb migration strategy consistent"
Baolin Wang has fixed a hugetlb migration issue, which should
improve hugetlb allocation reliability.
- Liu Shixin has hit an I/O meltdown caused by readahead in a
memory-tight memcg. Addressed in the series "Fix I/O high when
memory almost met memcg limit".
- In the series "mm/filemap: optimize folio adding and splitting"
Kairui Song has optimized pagecache insertion, yielding ~10%
performance improvement in one test.
- Baoquan He has cleaned up and consolidated the early zone
initialization code in the series "mm/mm_init.c: refactor
free_area_init_core()".
- Baoquan has also redone some MM initializatio code in the series
"mm/init: minor clean up and improvement".
- MM helper cleanups from Christoph Hellwig in his series "remove
follow_pfn".
- More cleanups from Matthew Wilcox in the series "Various
page->flags cleanups".
- Vlastimil Babka has contributed maintainability improvements in the
series "memcg_kmem hooks refactoring".
- More folio conversions and cleanups in Matthew Wilcox's series:
"Convert huge_zero_page to huge_zero_folio"
"khugepaged folio conversions"
"Remove page_idle and page_young wrappers"
"Use folio APIs in procfs"
"Clean up __folio_put()"
"Some cleanups for memory-failure"
"Remove page_mapping()"
"More folio compat code removal"
- David Hildenbrand chipped in with "fs/proc/task_mmu: convert
hugetlb functions to work on folis".
- Code consolidation and cleanup work related to GUP's handling of
hugetlbs in Peter Xu's series "mm/gup: Unify hugetlb, part 2".
- Rick Edgecombe has developed some fixes to stack guard gaps in the
series "Cover a guard gap corner case".
- Jinjiang Tu has fixed KSM's behaviour after a fork+exec in the
series "mm/ksm: fix ksm exec support for prctl".
- Baolin Wang has implemented NUMA balancing for multi-size THPs.
This is a simple first-cut implementation for now. The series is
"support multi-size THP numa balancing".
- Cleanups to vma handling helper functions from Matthew Wilcox in
the series "Unify vma_address and vma_pgoff_address".
- Some selftests maintenance work from Dev Jain in the series
"selftests/mm: mremap_test: Optimizations and style fixes".
- Improvements to the swapping of multi-size THPs from Ryan Roberts
in the series "Swap-out mTHP without splitting".
- Kefeng Wang has significantly optimized the handling of arm64's
permission page faults in the series
"arch/mm/fault: accelerate pagefault when badaccess"
"mm: remove arch's private VM_FAULT_BADMAP/BADACCESS"
- GUP cleanups from David Hildenbrand in "mm/gup: consistently call
it GUP-fast".
- hugetlb fault code cleanups from Vishal Moola in "Hugetlb fault
path to use struct vm_fault".
- selftests build fixes from John Hubbard in the series "Fix
selftests/mm build without requiring "make headers"".
- Memory tiering fixes/improvements from Ho-Ren (Jack) Chuang in the
series "Improved Memory Tier Creation for CPUless NUMA Nodes".
Fixes the initialization code so that migration between different
memory types works as intended.
- David Hildenbrand has improved follow_pte() and fixed an errant
driver in the series "mm: follow_pte() improvements and acrn
follow_pte() fixes".
- David also did some cleanup work on large folio mapcounts in his
series "mm: mapcount for large folios + page_mapcount() cleanups".
- Folio conversions in KSM in Alex Shi's series "transfer page to
folio in KSM".
- Barry Song has added some sysfs stats for monitoring multi-size
THP's in the series "mm: add per-order mTHP alloc and swpout
counters".
- Some zswap cleanups from Yosry Ahmed in the series "zswap
same-filled and limit checking cleanups".
- Matthew Wilcox has been looking at buffer_head code and found the
documentation to be lacking. The series is "Improve buffer head
documentation".
- Multi-size THPs get more work, this time from Lance Yang. His
series "mm/madvise: enhance lazyfreeing with mTHP in madvise_free"
optimizes the freeing of these things.
- Kemeng Shi has added more userspace-visible writeback
instrumentation in the series "Improve visibility of writeback".
- Kemeng Shi then sent some maintenance work on top in the series
"Fix and cleanups to page-writeback".
- Matthew Wilcox reduces mmap_lock traffic in the anon vma code in
the series "Improve anon_vma scalability for anon VMAs". Intel's
test bot reported an improbable 3x improvement in one test.
- SeongJae Park adds some DAMON feature work in the series
"mm/damon: add a DAMOS filter type for page granularity access recheck"
"selftests/damon: add DAMOS quota goal test"
- Also some maintenance work in the series
"mm/damon/paddr: simplify page level access re-check for pageout"
"mm/damon: misc fixes and improvements"
- David Hildenbrand has disabled some known-to-fail selftests ni the
series "selftests: mm: cow: flag vmsplice() hugetlb tests as
XFAIL".
- memcg metadata storage optimizations from Shakeel Butt in "memcg:
reduce memory consumption by memcg stats".
- DAX fixes and maintenance work from Vishal Verma in the series
"dax/bus.c: Fixups for dax-bus locking""
* tag 'mm-stable-2024-05-17-19-19' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (426 commits)
memcg, oom: cleanup unused memcg_oom_gfp_mask and memcg_oom_order
selftests/mm: hugetlb_madv_vs_map: avoid test skipping by querying hugepage size at runtime
mm/hugetlb: add missing VM_FAULT_SET_HINDEX in hugetlb_wp
mm/hugetlb: add missing VM_FAULT_SET_HINDEX in hugetlb_fault
selftests: cgroup: add tests to verify the zswap writeback path
mm: memcg: make alloc_mem_cgroup_per_node_info() return bool
mm/damon/core: fix return value from damos_wmark_metric_value
mm: do not update memcg stats for NR_{FILE/SHMEM}_PMDMAPPED
selftests: cgroup: remove redundant enabling of memory controller
Docs/mm/damon/maintainer-profile: allow posting patches based on damon/next tree
Docs/mm/damon/maintainer-profile: change the maintainer's timezone from PST to PT
Docs/mm/damon/design: use a list for supported filters
Docs/admin-guide/mm/damon/usage: fix wrong schemes effective quota update command
Docs/admin-guide/mm/damon/usage: fix wrong example of DAMOS filter matching sysfs file
selftests/damon: classify tests for functionalities and regressions
selftests/damon/_damon_sysfs: use 'is' instead of '==' for 'None'
selftests/damon/_damon_sysfs: find sysfs mount point from /proc/mounts
selftests/damon/_damon_sysfs: check errors from nr_schemes file reads
mm/damon/core: initialize ->esz_bp from damos_quota_init_priv()
selftests/damon: add a test for DAMOS quota goal
...
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Suren Baghdasaryan
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22d407b164 |
lib: add allocation tagging support for memory allocation profiling
Introduce CONFIG_MEM_ALLOC_PROFILING which provides definitions to easily instrument memory allocators. It registers an "alloc_tags" codetag type with /proc/allocinfo interface to output allocation tag information when the feature is enabled. CONFIG_MEM_ALLOC_PROFILING_DEBUG is provided for debugging the memory allocation profiling instrumentation. Memory allocation profiling can be enabled or disabled at runtime using /proc/sys/vm/mem_profiling sysctl when CONFIG_MEM_ALLOC_PROFILING_DEBUG=n. CONFIG_MEM_ALLOC_PROFILING_ENABLED_BY_DEFAULT enables memory allocation profiling by default. [surenb@google.com: Documentation/filesystems/proc.rst: fix allocinfo title] Link: https://lkml.kernel.org/r/20240326073813.727090-1-surenb@google.com [surenb@google.com: do limited memory accounting for modules with ARCH_NEEDS_WEAK_PER_CPU] Link: https://lkml.kernel.org/r/20240402180933.1663992-2-surenb@google.com [klarasmodin@gmail.com: explicitly include irqflags.h in alloc_tag.h] Link: https://lkml.kernel.org/r/20240407133252.173636-1-klarasmodin@gmail.com [surenb@google.com: fix alloc_tag_init() to prevent passing NULL to PTR_ERR()] Link: https://lkml.kernel.org/r/20240417003349.2520094-1-surenb@google.com Link: https://lkml.kernel.org/r/20240321163705.3067592-14-surenb@google.com Signed-off-by: Suren Baghdasaryan <surenb@google.com> Co-developed-by: Kent Overstreet <kent.overstreet@linux.dev> Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev> Signed-off-by: Klara Modin <klarasmodin@gmail.com> Tested-by: Kees Cook <keescook@chromium.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Alex Gaynor <alex.gaynor@gmail.com> Cc: Alice Ryhl <aliceryhl@google.com> Cc: Andreas Hindborg <a.hindborg@samsung.com> Cc: Benno Lossin <benno.lossin@proton.me> Cc: "Björn Roy Baron" <bjorn3_gh@protonmail.com> Cc: Boqun Feng <boqun.feng@gmail.com> Cc: Christoph Lameter <cl@linux.com> Cc: Dennis Zhou <dennis@kernel.org> Cc: Gary Guo <gary@garyguo.net> Cc: Miguel Ojeda <ojeda@kernel.org> Cc: Pasha Tatashin <pasha.tatashin@soleen.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Tejun Heo <tj@kernel.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Wedson Almeida Filho <wedsonaf@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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Pasha Tatashin
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212c5c078d |
iommu: account IOMMU allocated memory
In order to be able to limit the amount of memory that is allocated by IOMMU subsystem, the memory must be accounted. Account IOMMU as part of the secondary pagetables as it was discussed at LPC. The value of SecPageTables now contains mmeory allocation by IOMMU and KVM. There is a difference between GFP_ACCOUNT and what NR_IOMMU_PAGES shows. GFP_ACCOUNT is set only where it makes sense to charge to user processes, i.e. IOMMU Page Tables, but there more IOMMU shared data that should not really be charged to a specific process. Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com> Acked-by: David Rientjes <rientjes@google.com> Tested-by: Bagas Sanjaya <bagasdotme@gmail.com> Link: https://lore.kernel.org/r/20240413002522.1101315-12-pasha.tatashin@soleen.com Signed-off-by: Joerg Roedel <jroedel@suse.de> |
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Christoph Anton Mitterer
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2d1ab26ace |
docs: proc.rst: comm: mention the included NUL
Indicate that the actual value will be one character less. Signed-off-by: Christoph Anton Mitterer <mail@christoph.anton.mitterer.name> Link: https://lore.kernel.org/r/20240205154100.736499-1-mail@christoph.anton.mitterer.name [jc: did s/null/NUL/ ] Signed-off-by: Jonathan Corbet <corbet@lwn.net> |
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Ryan Roberts
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3485b88390 |
mm: thp: introduce multi-size THP sysfs interface
In preparation for adding support for anonymous multi-size THP, introduce new sysfs structure that will be used to control the new behaviours. A new directory is added under transparent_hugepage for each supported THP size, and contains an `enabled` file, which can be set to "inherit" (to inherit the global setting), "always", "madvise" or "never". For now, the kernel still only supports PMD-sized anonymous THP, so only 1 directory is populated. The first half of the change converts transhuge_vma_suitable() and hugepage_vma_check() so that they take a bitfield of orders for which the user wants to determine support, and the functions filter out all the orders that can't be supported, given the current sysfs configuration and the VMA dimensions. The resulting functions are renamed to thp_vma_suitable_orders() and thp_vma_allowable_orders() respectively. Convenience functions that take a single, unencoded order and return a boolean are also defined as thp_vma_suitable_order() and thp_vma_allowable_order(). The second half of the change implements the new sysfs interface. It has been done so that each supported THP size has a `struct thpsize`, which describes the relevant metadata and is itself a kobject. This is pretty minimal for now, but should make it easy to add new per-thpsize files to the interface if needed in future (e.g. per-size defrag). Rather than keep the `enabled` state directly in the struct thpsize, I've elected to directly encode it into huge_anon_orders_[always|madvise|inherit] bitfields since this reduces the amount of work required in thp_vma_allowable_orders() which is called for every page fault. See Documentation/admin-guide/mm/transhuge.rst, as modified by this commit, for details of how the new sysfs interface works. [ryan.roberts@arm.com: fix build warning when CONFIG_SYSFS is disabled] Link: https://lkml.kernel.org/r/20231211125320.3997543-1-ryan.roberts@arm.com Link: https://lkml.kernel.org/r/20231207161211.2374093-4-ryan.roberts@arm.com Signed-off-by: Ryan Roberts <ryan.roberts@arm.com> Reviewed-by: Barry Song <v-songbaohua@oppo.com> Tested-by: Kefeng Wang <wangkefeng.wang@huawei.com> Tested-by: John Hubbard <jhubbard@nvidia.com> Acked-by: David Hildenbrand <david@redhat.com> Cc: Alistair Popple <apopple@nvidia.com> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: David Rientjes <rientjes@google.com> Cc: "Huang, Ying" <ying.huang@intel.com> Cc: Hugh Dickins <hughd@google.com> Cc: Itaru Kitayama <itaru.kitayama@gmail.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Luis Chamberlain <mcgrof@kernel.org> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Yang Shi <shy828301@gmail.com> Cc: Yin Fengwei <fengwei.yin@intel.com> Cc: Yu Zhao <yuzhao@google.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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Paul E. McKenney
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acbc3ecb80 |
doc: Add /proc/bootconfig to proc.rst
Add /proc/bootconfig description to Documentation/filesystems/proc.rst. Link: https://lore.kernel.org/all/20231005171747.541123-3-paulmck@kernel.org/ Reported-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Paul E. McKenney <paulmck@kernel.org> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> |
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Paul E. McKenney
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1c20c65ea0 |
doc: Update /proc/cmdline documentation to include boot config
Update the /proc/cmdline documentation to explicitly state that this file provides kernel boot parameters obtained via boot config from the kernel image as well as those supplied by the boot loader. Link: https://lore.kernel.org/all/20231005171747.541123-1-paulmck@kernel.org/ Signed-off-by: Paul E. McKenney <paulmck@kernel.org> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Arnd Bergmann <arnd@kernel.org> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> |
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Linus Torvalds
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5eea5820c7 |
Merge tag 'mm-stable-2023-09-04-14-00' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull more MM updates from Andrew Morton: - Stefan Roesch has added ksm statistics to /proc/pid/smaps - Also a number of singleton patches, mainly cleanups and leftovers * tag 'mm-stable-2023-09-04-14-00' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: mm/kmemleak: move up cond_resched() call in page scanning loop mm: page_alloc: remove stale CMA guard code MAINTAINERS: add rmap.h to mm entry rmap: remove anon_vma_link() nommu stub proc/ksm: add ksm stats to /proc/pid/smaps mm/hwpoison: rename hwp_walk* to hwpoison_walk* mm: memory-failure: add PageOffline() check |
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Stefan Roesch
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8b47933544 |
proc/ksm: add ksm stats to /proc/pid/smaps
With madvise and prctl KSM can be enabled for different VMA's. Once it is enabled we can query how effective KSM is overall. However we cannot easily query if an individual VMA benefits from KSM. This commit adds a KSM section to the /prod/<pid>/smaps file. It reports how many of the pages are KSM pages. Note that KSM-placed zeropages are not included, only actual KSM pages. Here is a typical output: 7f420a000000-7f421a000000 rw-p 00000000 00:00 0 Size: 262144 kB KernelPageSize: 4 kB MMUPageSize: 4 kB Rss: 51212 kB Pss: 8276 kB Shared_Clean: 172 kB Shared_Dirty: 42996 kB Private_Clean: 196 kB Private_Dirty: 7848 kB Referenced: 15388 kB Anonymous: 51212 kB KSM: 41376 kB LazyFree: 0 kB AnonHugePages: 0 kB ShmemPmdMapped: 0 kB FilePmdMapped: 0 kB Shared_Hugetlb: 0 kB Private_Hugetlb: 0 kB Swap: 202016 kB SwapPss: 3882 kB Locked: 0 kB THPeligible: 0 ProtectionKey: 0 ksm_state: 0 ksm_skip_base: 0 ksm_skip_count: 0 VmFlags: rd wr mr mw me nr mg anon This information also helps with the following workflow: - First enable KSM for all the VMA's of a process with prctl. - Then analyze with the above smaps report which VMA's benefit the most - Change the application (if possible) to add the corresponding madvise calls for the VMA's that benefit the most [shr@devkernel.io: v5] Link: https://lkml.kernel.org/r/20230823170107.1457915-1-shr@devkernel.io Link: https://lkml.kernel.org/r/20230822180539.1424843-1-shr@devkernel.io Signed-off-by: Stefan Roesch <shr@devkernel.io> Reviewed-by: David Hildenbrand <david@redhat.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Rik van Riel <riel@surriel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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Linus Torvalds
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df57721f9a |
Merge tag 'x86_shstk_for_6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 shadow stack support from Dave Hansen: "This is the long awaited x86 shadow stack support, part of Intel's Control-flow Enforcement Technology (CET). CET consists of two related security features: shadow stacks and indirect branch tracking. This series implements just the shadow stack part of this feature, and just for userspace. The main use case for shadow stack is providing protection against return oriented programming attacks. It works by maintaining a secondary (shadow) stack using a special memory type that has protections against modification. When executing a CALL instruction, the processor pushes the return address to both the normal stack and to the special permission shadow stack. Upon RET, the processor pops the shadow stack copy and compares it to the normal stack copy. For more information, refer to the links below for the earlier versions of this patch set" Link: https://lore.kernel.org/lkml/20220130211838.8382-1-rick.p.edgecombe@intel.com/ Link: https://lore.kernel.org/lkml/20230613001108.3040476-1-rick.p.edgecombe@intel.com/ * tag 'x86_shstk_for_6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (47 commits) x86/shstk: Change order of __user in type x86/ibt: Convert IBT selftest to asm x86/shstk: Don't retry vm_munmap() on -EINTR x86/kbuild: Fix Documentation/ reference x86/shstk: Move arch detail comment out of core mm x86/shstk: Add ARCH_SHSTK_STATUS x86/shstk: Add ARCH_SHSTK_UNLOCK x86: Add PTRACE interface for shadow stack selftests/x86: Add shadow stack test x86/cpufeatures: Enable CET CR4 bit for shadow stack x86/shstk: Wire in shadow stack interface x86: Expose thread features in /proc/$PID/status x86/shstk: Support WRSS for userspace x86/shstk: Introduce map_shadow_stack syscall x86/shstk: Check that signal frame is shadow stack mem x86/shstk: Check that SSP is aligned on sigreturn x86/shstk: Handle signals for shadow stack x86/shstk: Introduce routines modifying shstk x86/shstk: Handle thread shadow stack x86/shstk: Add user-mode shadow stack support ... |
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Bjorn Helgaas
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d56b699d76 |
Documentation: Fix typos
Fix typos in Documentation. Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Link: https://lore.kernel.org/r/20230814212822.193684-4-helgaas@kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net> |
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Yu-cheng Yu
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54007f8182 |
mm: Introduce VM_SHADOW_STACK for shadow stack memory
New hardware extensions implement support for shadow stack memory, such as x86 Control-flow Enforcement Technology (CET). Add a new VM flag to identify these areas, for example, to be used to properly indicate shadow stack PTEs to the hardware. Shadow stack VMA creation will be tightly controlled and limited to anonymous memory to make the implementation simpler and since that is all that is required. The solution will rely on pte_mkwrite() to create the shadow stack PTEs, so it will not be required for vm_get_page_prot() to learn how to create shadow stack memory. For this reason document that VM_SHADOW_STACK should not be mixed with VM_SHARED. Co-developed-by: Rick Edgecombe <rick.p.edgecombe@intel.com> Signed-off-by: Yu-cheng Yu <yu-cheng.yu@intel.com> Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Reviewed-by: Mark Brown <broonie@kernel.org> Acked-by: Mike Rapoport (IBM) <rppt@kernel.org> Acked-by: David Hildenbrand <david@redhat.com> Tested-by: Mark Brown <broonie@kernel.org> Tested-by: Pengfei Xu <pengfei.xu@intel.com> Tested-by: John Allen <john.allen@amd.com> Tested-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/all/20230613001108.3040476-15-rick.p.edgecombe%40intel.com |
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Linus Torvalds
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33afd4b763 |
Merge tag 'mm-nonmm-stable-2023-04-27-16-01' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull non-MM updates from Andrew Morton: "Mainly singleton patches all over the place. Series of note are: - updates to scripts/gdb from Glenn Washburn - kexec cleanups from Bjorn Helgaas" * tag 'mm-nonmm-stable-2023-04-27-16-01' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (50 commits) mailmap: add entries for Paul Mackerras libgcc: add forward declarations for generic library routines mailmap: add entry for Oleksandr ocfs2: reduce ioctl stack usage fs/proc: add Kthread flag to /proc/$pid/status ia64: fix an addr to taddr in huge_pte_offset() checkpatch: introduce proper bindings license check epoll: rename global epmutex scripts/gdb: add GDB convenience functions $lx_dentry_name() and $lx_i_dentry() scripts/gdb: create linux/vfs.py for VFS related GDB helpers uapi/linux/const.h: prefer ISO-friendly __typeof__ delayacct: track delays from IRQ/SOFTIRQ scripts/gdb: timerlist: convert int chunks to str scripts/gdb: print interrupts scripts/gdb: raise error with reduced debugging information scripts/gdb: add a Radix Tree Parser lib/rbtree: use '+' instead of '|' for setting color. proc/stat: remove arch_idle_time() checkpatch: check for misuse of the link tags checkpatch: allow Closes tags with links ... |
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Linus Torvalds
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7fa8a8ee94 |
Merge tag 'mm-stable-2023-04-27-15-30' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull MM updates from Andrew Morton:
- Nick Piggin's "shoot lazy tlbs" series, to improve the peformance of
switching from a user process to a kernel thread.
- More folio conversions from Kefeng Wang, Zhang Peng and Pankaj
Raghav.
- zsmalloc performance improvements from Sergey Senozhatsky.
- Yue Zhao has found and fixed some data race issues around the
alteration of memcg userspace tunables.
- VFS rationalizations from Christoph Hellwig:
- removal of most of the callers of write_one_page()
- make __filemap_get_folio()'s return value more useful
- Luis Chamberlain has changed tmpfs so it no longer requires swap
backing. Use `mount -o noswap'.
- Qi Zheng has made the slab shrinkers operate locklessly, providing
some scalability benefits.
- Keith Busch has improved dmapool's performance, making part of its
operations O(1) rather than O(n).
- Peter Xu adds the UFFD_FEATURE_WP_UNPOPULATED feature to userfaultd,
permitting userspace to wr-protect anon memory unpopulated ptes.
- Kirill Shutemov has changed MAX_ORDER's meaning to be inclusive
rather than exclusive, and has fixed a bunch of errors which were
caused by its unintuitive meaning.
- Axel Rasmussen give userfaultfd the UFFDIO_CONTINUE_MODE_WP feature,
which causes minor faults to install a write-protected pte.
- Vlastimil Babka has done some maintenance work on vma_merge():
cleanups to the kernel code and improvements to our userspace test
harness.
- Cleanups to do_fault_around() by Lorenzo Stoakes.
- Mike Rapoport has moved a lot of initialization code out of various
mm/ files and into mm/mm_init.c.
- Lorenzo Stoakes removd vmf_insert_mixed_prot(), which was added for
DRM, but DRM doesn't use it any more.
- Lorenzo has also coverted read_kcore() and vread() to use iterators
and has thereby removed the use of bounce buffers in some cases.
- Lorenzo has also contributed further cleanups of vma_merge().
- Chaitanya Prakash provides some fixes to the mmap selftesting code.
- Matthew Wilcox changes xfs and afs so they no longer take sleeping
locks in ->map_page(), a step towards RCUification of pagefaults.
- Suren Baghdasaryan has improved mmap_lock scalability by switching to
per-VMA locking.
- Frederic Weisbecker has reworked the percpu cache draining so that it
no longer causes latency glitches on cpu isolated workloads.
- Mike Rapoport cleans up and corrects the ARCH_FORCE_MAX_ORDER Kconfig
logic.
- Liu Shixin has changed zswap's initialization so we no longer waste a
chunk of memory if zswap is not being used.
- Yosry Ahmed has improved the performance of memcg statistics
flushing.
- David Stevens has fixed several issues involving khugepaged,
userfaultfd and shmem.
- Christoph Hellwig has provided some cleanup work to zram's IO-related
code paths.
- David Hildenbrand has fixed up some issues in the selftest code's
testing of our pte state changing.
- Pankaj Raghav has made page_endio() unneeded and has removed it.
- Peter Xu contributed some rationalizations of the userfaultfd
selftests.
- Yosry Ahmed has fixed an issue around memcg's page recalim
accounting.
- Chaitanya Prakash has fixed some arm-related issues in the
selftests/mm code.
- Longlong Xia has improved the way in which KSM handles hwpoisoned
pages.
- Peter Xu fixes a few issues with uffd-wp at fork() time.
- Stefan Roesch has changed KSM so that it may now be used on a
per-process and per-cgroup basis.
* tag 'mm-stable-2023-04-27-15-30' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (369 commits)
mm,unmap: avoid flushing TLB in batch if PTE is inaccessible
shmem: restrict noswap option to initial user namespace
mm/khugepaged: fix conflicting mods to collapse_file()
sparse: remove unnecessary 0 values from rc
mm: move 'mmap_min_addr' logic from callers into vm_unmapped_area()
hugetlb: pte_alloc_huge() to replace huge pte_alloc_map()
maple_tree: fix allocation in mas_sparse_area()
mm: do not increment pgfault stats when page fault handler retries
zsmalloc: allow only one active pool compaction context
selftests/mm: add new selftests for KSM
mm: add new KSM process and sysfs knobs
mm: add new api to enable ksm per process
mm: shrinkers: fix debugfs file permissions
mm: don't check VMA write permissions if the PTE/PMD indicates write permissions
migrate_pages_batch: fix statistics for longterm pin retry
userfaultfd: use helper function range_in_vma()
lib/show_mem.c: use for_each_populated_zone() simplify code
mm: correct arg in reclaim_pages()/reclaim_clean_pages_from_list()
fs/buffer: convert create_page_buffers to folio_create_buffers
fs/buffer: add folio_create_empty_buffers helper
...
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Chunguang Wu
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522dc4e5f5 |
fs/proc: add Kthread flag to /proc/$pid/status
The command `ps -ef ` and `top -c` mark kernel thread by '[' and ']', but sometimes the result is not correct. The task->flags in /proc/$pid/stat is good, but we need remember the value of PF_KTHREAD is 0x00200000 and convert dec to hex. If we have no binary program and shell script which read /proc/$pid/stat, we can know it directly by `cat /proc/$pid/status`. Link: https://lkml.kernel.org/r/20230416052404.2920-1-fullspring2018@gmail.com Signed-off-by: Chunguang Wu <fullspring2018@gmail.com> Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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Tomas Mudrunka
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bd23024b97 |
mm/memtest: add results of early memtest to /proc/meminfo
Currently the memtest results were only presented in dmesg. When running a large fleet of devices without ECC RAM it's currently not easy to do bulk monitoring for memory corruption. You have to parse dmesg, but that's a ring buffer so the error might disappear after some time. In general I do not consider dmesg to be a great API to query RAM status. In several companies I've seen such errors remain undetected and cause issues for way too long. So I think it makes sense to provide a monitoring API, so that we can safely detect and act upon them. This adds /proc/meminfo entry which can be easily used by scripts. Link: https://lkml.kernel.org/r/20230321103430.7130-1-tomas.mudrunka@gmail.com Signed-off-by: Tomas Mudrunka <tomas.mudrunka@gmail.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Mike Rapoport (IBM) <rppt@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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Randy Dunlap
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d2ea66a69f |
Documentation: fs/proc: corrections and update
Update URL for the latest online version of this document. Correct "files" to "fields" in a few places. Update /proc/scsi, /proc/stat, and /proc/fs/ext4 information. Drop /usr/src/ from the location of the kernel source tree. Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: linux-doc@vger.kernel.org Cc: linux-fsdevel@vger.kernel.org Reviewed-by: Christian Brauner <brauner@kernel.org> Link: https://lore.kernel.org/r/20230314060347.605-1-rdunlap@infradead.org Signed-off-by: Jonathan Corbet <corbet@lwn.net> |
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Yang Yang
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8b0a211d31 |
docs: proc.rst: add softnet_stat to /proc/net table
/proc/net/softnet_stat exists for a long time, but proc.rst miss it. Softnet_stat shows some statistics of struct softnet_data of online CPUs. Struct softnet_data manages incoming and output packets on per-CPU queues. Note that fastroute and cpu_collision in softnet_stat are obsolete and their value is always 0. Signed-off-by: Yang Yang <yang.yang29@zte.com.cn> Reviewed-by: xu xin <xu.xin16@zte.com.cn> Reviewed-by: Zhang Yunkai <zhang.yunkai@zte.com.cn> Link: https://lore.kernel.org/r/202212091421536982085@zte.com.cn Signed-off-by: Jonathan Corbet <corbet@lwn.net> |
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Linus Torvalds
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e2ca6ba6ba |
Merge tag 'mm-stable-2022-12-13' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull MM updates from Andrew Morton: - More userfaultfs work from Peter Xu - Several convert-to-folios series from Sidhartha Kumar and Huang Ying - Some filemap cleanups from Vishal Moola - David Hildenbrand added the ability to selftest anon memory COW handling - Some cpuset simplifications from Liu Shixin - Addition of vmalloc tracing support by Uladzislau Rezki - Some pagecache folioifications and simplifications from Matthew Wilcox - A pagemap cleanup from Kefeng Wang: we have VM_ACCESS_FLAGS, so use it - Miguel Ojeda contributed some cleanups for our use of the __no_sanitize_thread__ gcc keyword. This series should have been in the non-MM tree, my bad - Naoya Horiguchi improved the interaction between memory poisoning and memory section removal for huge pages - DAMON cleanups and tuneups from SeongJae Park - Tony Luck fixed the handling of COW faults against poisoned pages - Peter Xu utilized the PTE marker code for handling swapin errors - Hugh Dickins reworked compound page mapcount handling, simplifying it and making it more efficient - Removal of the autonuma savedwrite infrastructure from Nadav Amit and David Hildenbrand - zram support for multiple compression streams from Sergey Senozhatsky - David Hildenbrand reworked the GUP code's R/O long-term pinning so that drivers no longer need to use the FOLL_FORCE workaround which didn't work very well anyway - Mel Gorman altered the page allocator so that local IRQs can remnain enabled during per-cpu page allocations - Vishal Moola removed the try_to_release_page() wrapper - Stefan Roesch added some per-BDI sysfs tunables which are used to prevent network block devices from dirtying excessive amounts of pagecache - David Hildenbrand did some cleanup and repair work on KSM COW breaking - Nhat Pham and Johannes Weiner have implemented writeback in zswap's zsmalloc backend - Brian Foster has fixed a longstanding corner-case oddity in file[map]_write_and_wait_range() - sparse-vmemmap changes for MIPS, LoongArch and NIOS2 from Feiyang Chen - Shiyang Ruan has done some work on fsdax, to make its reflink mode work better under xfstests. Better, but still not perfect - Christoph Hellwig has removed the .writepage() method from several filesystems. They only need .writepages() - Yosry Ahmed wrote a series which fixes the memcg reclaim target beancounting - David Hildenbrand has fixed some of our MM selftests for 32-bit machines - Many singleton patches, as usual * tag 'mm-stable-2022-12-13' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (313 commits) mm/hugetlb: set head flag before setting compound_order in __prep_compound_gigantic_folio mm: mmu_gather: allow more than one batch of delayed rmaps mm: fix typo in struct pglist_data code comment kmsan: fix memcpy tests mm: add cond_resched() in swapin_walk_pmd_entry() mm: do not show fs mm pc for VM_LOCKONFAULT pages selftests/vm: ksm_functional_tests: fixes for 32bit selftests/vm: cow: fix compile warning on 32bit selftests/vm: madv_populate: fix missing MADV_POPULATE_(READ|WRITE) definitions mm/gup_test: fix PIN_LONGTERM_TEST_READ with highmem mm,thp,rmap: fix races between updates of subpages_mapcount mm: memcg: fix swapcached stat accounting mm: add nodes= arg to memory.reclaim mm: disable top-tier fallback to reclaim on proactive reclaim selftests: cgroup: make sure reclaim target memcg is unprotected selftests: cgroup: refactor proactive reclaim code to reclaim_until() mm: memcg: fix stale protection of reclaim target memcg mm/mmap: properly unaccount memory on mas_preallocate() failure omfs: remove ->writepage jfs: remove ->writepage ... |
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Linus Torvalds
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8702f2c611 |
Merge tag 'mm-nonmm-stable-2022-12-12' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull non-MM updates from Andrew Morton: - A ptrace API cleanup series from Sergey Shtylyov - Fixes and cleanups for kexec from ye xingchen - nilfs2 updates from Ryusuke Konishi - squashfs feature work from Xiaoming Ni: permit configuration of the filesystem's compression concurrency from the mount command line - A series from Akinobu Mita which addresses bound checking errors when writing to debugfs files - A series from Yang Yingliang to address rapidio memory leaks - A series from Zheng Yejian to address possible overflow errors in encode_comp_t() - And a whole shower of singleton patches all over the place * tag 'mm-nonmm-stable-2022-12-12' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (79 commits) ipc: fix memory leak in init_mqueue_fs() hfsplus: fix bug causing custom uid and gid being unable to be assigned with mount rapidio: devices: fix missing put_device in mport_cdev_open kcov: fix spelling typos in comments hfs: Fix OOB Write in hfs_asc2mac hfs: fix OOB Read in __hfs_brec_find relay: fix type mismatch when allocating memory in relay_create_buf() ocfs2: always read both high and low parts of dinode link count io-mapping: move some code within the include guarded section kernel: kcsan: kcsan_test: build without structleak plugin mailmap: update email for Iskren Chernev eventfd: change int to __u64 in eventfd_signal() ifndef CONFIG_EVENTFD rapidio: fix possible UAF when kfifo_alloc() fails relay: use strscpy() is more robust and safer cpumask: limit visibility of FORCE_NR_CPUS acct: fix potential integer overflow in encode_comp_t() acct: fix accuracy loss for input value of encode_comp_t() linux/init.h: include <linux/build_bug.h> and <linux/stringify.h> rapidio: rio: fix possible name leak in rio_register_mport() rapidio: fix possible name leaks when rio_add_device() fails ... |
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Pasha Tatashin
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d09e8ca6cb |
mm: anonymous shared memory naming
Since commit
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Ivan Babrou
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f1f1f25699 |
proc: report open files as size in stat() for /proc/pid/fd
Many monitoring tools include open file count as a metric. Currently the only way to get this number is to enumerate the files in /proc/pid/fd. The problem with the current approach is that it does many things people generally don't care about when they need one number for a metric. In our tests for cadvisor, which reports open file counts per cgroup, we observed that reading the number of open files is slow. Out of 35.23% of CPU time spent in `proc_readfd_common`, we see 29.43% spent in `proc_fill_cache`, which is responsible for filling dentry info. Some of this extra time is spinlock contention, but it's a contention for the lock we don't want to take to begin with. We considered putting the number of open files in /proc/pid/status. Unfortunately, counting the number of fds involves iterating the open_files bitmap, which has a linear complexity in proportion with the number of open files (bitmap slots really, but it's close). We don't want to make /proc/pid/status any slower, so instead we put this info in /proc/pid/fd as a size member of the stat syscall result. Previously the reported number was zero, so there's very little risk of breaking anything, while still providing a somewhat logical way to count the open files with a fallback if it's zero. RFC for this patch included iterating open fds under RCU. Thanks to Frank Hofmann for the suggestion to use the bitmap instead. Previously: ``` $ sudo stat /proc/1/fd | head -n2 File: /proc/1/fd Size: 0 Blocks: 0 IO Block: 1024 directory ``` With this patch: ``` $ sudo stat /proc/1/fd | head -n2 File: /proc/1/fd Size: 65 Blocks: 0 IO Block: 1024 directory ``` Correctness check: ``` $ sudo ls /proc/1/fd | wc -l 65 ``` I added the docs for /proc/<pid>/fd while I'm at it. [ivan@cloudflare.com: use bitmap_weight() to count the bits] Link: https://lkml.kernel.org/r/20221018045844.37697-1-ivan@cloudflare.com [akpm@linux-foundation.org: include linux/bitmap.h for bitmap_weight()] [ivan@cloudflare.com: return errno from proc_fd_getattr() instead of setting negative size] Link: https://lkml.kernel.org/r/20221024173140.30673-1-ivan@cloudflare.com Link: https://lkml.kernel.org/r/20220922224027.59266-1-ivan@cloudflare.com Signed-off-by: Ivan Babrou <ivan@cloudflare.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Christoph Anton Mitterer <mail@christoph.anton.mitterer.name> Cc: David Hildenbrand <david@redhat.com> Cc: David Laight <David.Laight@ACULAB.COM> Cc: Ivan Babrou <ivan@cloudflare.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kalesh Singh <kaleshsingh@google.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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Chen Linxuan
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df61e945e1 |
Documentation: update the description of TracerPid in procfs.rst
When the tracer of process is outside of current pid namespace, field `TracerPid` in /proc/<pid>/status will be 0, too, just like this process not have been traced. This is because that function `task_pid_nr_ns` used to get the pid of tracer will return 0 in this situation. Co-authored-by: Yuan Haisheng <heysion@deepin.com> Signed-off-by: Chen Linxuan <chenlinxuan@uniontech.com> Link: https://lore.kernel.org/r/20221102081517.19770-1-chenlinxuan@uniontech.com Signed-off-by: Jonathan Corbet <corbet@lwn.net> |
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Yosry Ahmed
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ebc97a52b5 |
mm: add NR_SECONDARY_PAGETABLE to count secondary page table uses.
We keep track of several kernel memory stats (total kernel memory, page
tables, stack, vmalloc, etc) on multiple levels (global, per-node,
per-memcg, etc). These stats give insights to users to how much memory
is used by the kernel and for what purposes.
Currently, memory used by KVM mmu is not accounted in any of those
kernel memory stats. This patch series accounts the memory pages
used by KVM for page tables in those stats in a new
NR_SECONDARY_PAGETABLE stat. This stat can be later extended to account
for other types of secondary pages tables (e.g. iommu page tables).
KVM has a decent number of large allocations that aren't for page
tables, but for most of them, the number/size of those allocations
scales linearly with either the number of vCPUs or the amount of memory
assigned to the VM. KVM's secondary page table allocations do not scale
linearly, especially when nested virtualization is in use.
From a KVM perspective, NR_SECONDARY_PAGETABLE will scale with KVM's
per-VM pages_{4k,2m,1g} stats unless the guest is doing something
bizarre (e.g. accessing only 4kb chunks of 2mb pages so that KVM is
forced to allocate a large number of page tables even though the guest
isn't accessing that much memory). However, someone would need to either
understand how KVM works to make that connection, or know (or be told) to
go look at KVM's stats if they're running VMs to better decipher the stats.
Furthermore, having NR_PAGETABLE side-by-side with NR_SECONDARY_PAGETABLE
is informative. For example, when backing a VM with THP vs. HugeTLB,
NR_SECONDARY_PAGETABLE is roughly the same, but NR_PAGETABLE is an order
of magnitude higher with THP. So having this stat will at the very least
prove to be useful for understanding tradeoffs between VM backing types,
and likely even steer folks towards potential optimizations.
The original discussion with more details about the rationale:
https://lore.kernel.org/all/87ilqoi77b.wl-maz@kernel.org
This stat will be used by subsequent patches to count KVM mmu
memory usage.
Signed-off-by: Yosry Ahmed <yosryahmed@google.com>
Acked-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220823004639.2387269-2-yosryahmed@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
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Yang Shi
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cb55b83862 |
doc: proc: fix the description to THPeligible
The THPeligible bit shows 1 if and only if the VMA is eligible for allocating THP and the THP is also PMD mappable. Some misaligned file VMAs may be eligible for allocating THP but the THP can't be mapped by PMD. Make this more explicitly to avoid ambiguity. Link: https://lkml.kernel.org/r/20220616174840.1202070-8-shy828301@gmail.com Signed-off-by: Yang Shi <shy828301@gmail.com> Reviewed-by: Zach O'Keefe <zokeefe@google.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Miaohe Lin <linmiaohe@huawei.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |