2266 Commits

Author SHA1 Message Date
GuoHan Zhao
cd7e1fef5a xen/privcmd: unregister xenstore notifier on module exit
Commit 453b8fb68f ("xen/privcmd: restrict usage in
unprivileged domU") added a xenstore notifier to defer setting the
restriction target until Xenstore is ready.

XEN_PRIVCMD can be built as a module, but privcmd_exit() leaves that
notifier behind. Balance the notifier lifecycle by unregistering it on
module exit.

This is harmless even if xenstore was already ready at registration
time and the notifier was never queued on the chain.

Fixes: 453b8fb68f ("xen/privcmd: restrict usage in unprivileged domU")
Signed-off-by: GuoHan Zhao <zhaoguohan@kylinos.cn>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Message-ID: <20260325120246.252899-1-zhaoguohan@kylinos.cn>
2026-03-26 08:57:51 +01:00
Juergen Gross
1613462be6 xen/privcmd: add boot control for restricted usage in domU
When running in an unprivileged domU under Xen, the privcmd driver
is restricted to allow only hypercalls against a target domain, for
which the current domU is acting as a device model.

Add a boot parameter "unrestricted" to allow all hypercalls (the
hypervisor will still refuse destructive hypercalls affecting other
guests).

Make this new parameter effective only in case the domU wasn't started
using secure boot, as otherwise hypercalls targeting the domU itself
might result in violating the secure boot functionality.

This is achieved by adding another lockdown reason, which can be
tested to not being set when applying the "unrestricted" option.

This is part of XSA-482

Signed-off-by: Juergen Gross <jgross@suse.com>
---
V2:
- new patch
2026-03-20 12:06:01 +01:00
Juergen Gross
453b8fb68f xen/privcmd: restrict usage in unprivileged domU
The Xen privcmd driver allows to issue arbitrary hypercalls from
user space processes. This is normally no problem, as access is
usually limited to root and the hypervisor will deny any hypercalls
affecting other domains.

In case the guest is booted using secure boot, however, the privcmd
driver would be enabling a root user process to modify e.g. kernel
memory contents, thus breaking the secure boot feature.

The only known case where an unprivileged domU is really needing to
use the privcmd driver is the case when it is acting as the device
model for another guest. In this case all hypercalls issued via the
privcmd driver will target that other guest.

Fortunately the privcmd driver can already be locked down to allow
only hypercalls targeting a specific domain, but this mode can be
activated from user land only today.

The target domain can be obtained from Xenstore, so when not running
in dom0 restrict the privcmd driver to that target domain from the
beginning, resolving the potential problem of breaking secure boot.

This is XSA-482

Reported-by: Teddy Astie <teddy.astie@vates.tech>
Fixes: 1c5de1939c ("xen: add privcmd driver")
Signed-off-by: Juergen Gross <jgross@suse.com>
---
V2:
- defer reading from Xenstore if Xenstore isn't ready yet (Jan Beulich)
- wait in open() if target domain isn't known yet
- issue message in case no target domain found (Jan Beulich)
2026-03-20 12:05:41 +01:00
Linus Torvalds
0f912c8917 Merge tag 'for-linus-7.0-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull xen fixes from Juergen Gross:

 - a cleanup of arch/x86/kernel/head_64.S removing the pre-built page
   tables for Xen guests

 - a small comment update

 - another cleanup for Xen PVH guests mode

 - fix an issue with Xen PV-devices backed by driver domains

* tag 'for-linus-7.0-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen/xenbus: better handle backend crash
  xenbus: add xenbus_device parameter to xenbus_read_driver_state()
  x86/PVH: Use boot params to pass RSDP address in start_info page
  x86/xen: update outdated comment
  xen/acpi-processor: fix _CST detection using undersized evaluation buffer
  x86/xen: Build identity mapping page tables dynamically for XENPV
2026-03-07 07:44:32 -08:00
Juergen Gross
e2dcf90655 xen/xenbus: better handle backend crash
When the backend domain crashes, coordinated device cleanup is not
possible (as it involves waiting for the backend state change). In that
case, toolstack forcefully removes frontend xenstore entries.
xenbus_dev_changed() handles this case, and triggers device cleanup.
It's possible that toolstack manages to connect new device in that
place, before xenbus_dev_changed() notices the old one is missing. If
that happens, new one won't be probed and will forever remain in
XenbusStateInitialising.

Fix this by checking the frontend's state in Xenstore. In case it has
been reset to XenbusStateInitialising by Xen tools, consider this
being the result of an unplug+plug operation.

It's important that cleanup on such unplug doesn't modify Xenstore
entries (especially the "state" key) as it belong to the new device
to be probed - changing it would derail establishing connection to the
new backend (most likely, closing the device before it was even
connected). Handle this case by setting new xenbus_device->vanished
flag to true, and check it before changing state entry.

And even if xenbus_dev_changed() correctly detects the device was
forcefully removed, the cleanup handling is still racy. Since this whole
handling doesn't happened in a single Xenstore transaction, it's possible
that toolstack might put a new device there already. Avoid re-creating
the state key (which in the case of loosing the race would actually
close newly attached device).

The problem does not apply to frontend domain crash, as this case
involves coordinated cleanup.

Problem originally reported at
https://lore.kernel.org/xen-devel/aOZvivyZ9YhVWDLN@mail-itl/T/#t,
including reproduction steps.

Based-on-patch-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Tested-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Message-ID: <20260218095205.453657-3-jgross@suse.com>
2026-03-04 15:31:40 +01:00
Juergen Gross
82169dace4 xenbus: add xenbus_device parameter to xenbus_read_driver_state()
In order to prepare checking the xenbus device status in
xenbus_read_driver_state(), add the pointer to struct xenbus_device
as a parameter.

Tested-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: "Martin K. Petersen" <martin.petersen@oracle.com> # SCSI
Acked-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>	# drivers/pci/xen-pcifront.c
Signed-off-by: Juergen Gross <jgross@suse.com>
Message-ID: <20260218095205.453657-2-jgross@suse.com>
2026-03-04 15:31:40 +01:00
David Thomson
8b57227d59 xen/acpi-processor: fix _CST detection using undersized evaluation buffer
read_acpi_id() attempts to evaluate _CST using a stack buffer of
sizeof(union acpi_object) (48 bytes), but _CST returns a nested Package
of sub-Packages (one per C-state, each containing a register descriptor,
type, latency, and power) requiring hundreds of bytes. The evaluation
always fails with AE_BUFFER_OVERFLOW.

On modern systems using FFH/MWAIT entry (where pblk is zero), this
causes the function to return before setting the acpi_id_cst_present
bit. In check_acpi_ids(), flags.power is then zero for all Phase 2 CPUs
(physical CPUs beyond dom0's vCPU count), so push_cxx_to_hypervisor() is
never called for them.

On a system with dom0_max_vcpus=2 and 8 physical CPUs, only PCPUs 0-1
receive C-state data. PCPUs 2-7 are stuck in C0/C1 idle, unable to
enter C2/C3. This costs measurable wall power (4W observed on an Intel
Core Ultra 7 265K with Xen 4.20).

The function never uses the _CST return value -- it only needs to know
whether _CST exists. Replace the broken acpi_evaluate_object() call with
acpi_has_method(), which correctly detects _CST presence using
acpi_get_handle() without any buffer allocation. This brings C-state
detection to parity with the P-state path, which already works correctly
for Phase 2 CPUs.

Fixes: 59a5680291 ("xen/acpi-processor: C and P-state driver that uploads said data to hypervisor.")
Signed-off-by: David Thomson <dt@linux-mail.net>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Message-ID: <20260224093707.19679-1-dt@linux-mail.net>
2026-03-03 14:53:46 +01:00
Kees Cook
189f164e57 Convert remaining multi-line kmalloc_obj/flex GFP_KERNEL uses
Conversion performed via this Coccinelle script:

  // SPDX-License-Identifier: GPL-2.0-only
  // Options: --include-headers-for-types --all-includes --include-headers --keep-comments
  virtual patch

  @gfp depends on patch && !(file in "tools") && !(file in "samples")@
  identifier ALLOC = {kmalloc_obj,kmalloc_objs,kmalloc_flex,
 		    kzalloc_obj,kzalloc_objs,kzalloc_flex,
		    kvmalloc_obj,kvmalloc_objs,kvmalloc_flex,
		    kvzalloc_obj,kvzalloc_objs,kvzalloc_flex};
  @@

  	ALLOC(...
  -		, GFP_KERNEL
  	)

  $ make coccicheck MODE=patch COCCI=gfp.cocci

Build and boot tested x86_64 with Fedora 42's GCC and Clang:

Linux version 6.19.0+ (user@host) (gcc (GCC) 15.2.1 20260123 (Red Hat 15.2.1-7), GNU ld version 2.44-12.fc42) #1 SMP PREEMPT_DYNAMIC 1970-01-01
Linux version 6.19.0+ (user@host) (clang version 20.1.8 (Fedora 20.1.8-4.fc42), LLD 20.1.8) #1 SMP PREEMPT_DYNAMIC 1970-01-01

Signed-off-by: Kees Cook <kees@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2026-02-22 08:26:33 -08:00
Linus Torvalds
32a92f8c89 Convert more 'alloc_obj' cases to default GFP_KERNEL arguments
This converts some of the visually simpler cases that have been split
over multiple lines.  I only did the ones that are easy to verify the
resulting diff by having just that final GFP_KERNEL argument on the next
line.

Somebody should probably do a proper coccinelle script for this, but for
me the trivial script actually resulted in an assertion failure in the
middle of the script.  I probably had made it a bit _too_ trivial.

So after fighting that far a while I decided to just do some of the
syntactically simpler cases with variations of the previous 'sed'
scripts.

The more syntactically complex multi-line cases would mostly really want
whitespace cleanup anyway.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2026-02-21 20:03:00 -08:00
Linus Torvalds
323bbfcf1e Convert 'alloc_flex' family to use the new default GFP_KERNEL argument
This is the exact same thing as the 'alloc_obj()' version, only much
smaller because there are a lot fewer users of the *alloc_flex()
interface.

As with alloc_obj() version, this was done entirely with mindless brute
force, using the same script, except using 'flex' in the pattern rather
than 'objs*'.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2026-02-21 17:09:51 -08:00
Linus Torvalds
bf4afc53b7 Convert 'alloc_obj' family to use the new default GFP_KERNEL argument
This was done entirely with mindless brute force, using

    git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' |
        xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/'

to convert the new alloc_obj() users that had a simple GFP_KERNEL
argument to just drop that argument.

Note that due to the extreme simplicity of the scripting, any slightly
more complex cases spread over multiple lines would not be triggered:
they definitely exist, but this covers the vast bulk of the cases, and
the resulting diff is also then easier to check automatically.

For the same reason the 'flex' versions will be done as a separate
conversion.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2026-02-21 17:09:51 -08:00
Kees Cook
69050f8d6d treewide: Replace kmalloc with kmalloc_obj for non-scalar types
This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:

Single allocations:	kmalloc(sizeof(TYPE), ...)
are replaced with:	kmalloc_obj(TYPE, ...)

Array allocations:	kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with:	kmalloc_objs(TYPE, COUNT, ...)

Flex array allocations:	kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with:	kmalloc_flex(*PTR, FAM, COUNT, ...)

(where TYPE may also be *VAR)

The resulting allocations no longer return "void *", instead returning
"TYPE *".

Signed-off-by: Kees Cook <kees@kernel.org>
2026-02-21 01:02:28 -08:00
Linus Torvalds
57cb845067 Merge tag 'x86_paravirt_for_v7.0_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 paravirt updates from Borislav Petkov:

 - A nice cleanup to the paravirt code containing a unification of the
   paravirt clock interface, taming the include hell by splitting the
   pv_ops structure and removing of a bunch of obsolete code (Juergen
   Gross)

* tag 'x86_paravirt_for_v7.0_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits)
  x86/paravirt: Use XOR r32,r32 to clear register in pv_vcpu_is_preempted()
  x86/paravirt: Remove trailing semicolons from alternative asm templates
  x86/pvlocks: Move paravirt spinlock functions into own header
  x86/paravirt: Specify pv_ops array in paravirt macros
  x86/paravirt: Allow pv-calls outside paravirt.h
  objtool: Allow multiple pv_ops arrays
  x86/xen: Drop xen_mmu_ops
  x86/xen: Drop xen_cpu_ops
  x86/xen: Drop xen_irq_ops
  x86/paravirt: Move pv_native_*() prototypes to paravirt.c
  x86/paravirt: Introduce new paravirt-base.h header
  x86/paravirt: Move paravirt_sched_clock() related code into tsc.c
  x86/paravirt: Use common code for paravirt_steal_clock()
  riscv/paravirt: Use common code for paravirt_steal_clock()
  loongarch/paravirt: Use common code for paravirt_steal_clock()
  arm64/paravirt: Use common code for paravirt_steal_clock()
  arm/paravirt: Use common code for paravirt_steal_clock()
  sched: Move clock related paravirt code to kernel/sched
  paravirt: Remove asm/paravirt_api_clock.h
  x86/paravirt: Move thunk macros to paravirt_types.h
  ...
2026-02-10 19:01:45 -08:00
Linus Torvalds
33120a2f8f Merge tag 'for-linus-7.0-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull xen updates from Juergen Gross:

 - fix running as Xen PVH guest in 32-bit mode without PAE

 - fix PV device handling for suspend/resume when running as
   a Xen guest

 - clean up workqueue usage

 - fix the Xen balloon driver for PVH dom0

 - introduce the possibility to use hypercalls for console
   messages in unprivileged guests

 - enable Xen dom0 use of virtio devices in nested virtualization
   setups

 - simplify the xen-mcelog driver

* tag 'for-linus-7.0-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xenbus: Rename helpers to freeze/thaw/restore
  xenbus: Use .freeze/.thaw to handle xenbus devices
  xen/mcelog: simplify MCE_GETCLEAR_FLAGS using xchg()
  xen/balloon: improve accuracy of initial balloon target for dom0
  Partial revert "x86/xen: fix balloon target initialization for PVH dom0"
  xen: introduce xen_console_io option
  xen/virtio: Don't use grant-dma-ops when running as Dom0
  x86/xen/pvh: Enable PAE mode for 32-bit guest only when CONFIG_X86_PAE is set
  xen: privcmd: WQ_PERCPU added to alloc_workqueue users
  xen/events: replace use of system_wq with system_percpu_wq
2026-02-09 20:38:27 -08:00
Jason Andryuk
c307b6dc9c xenbus: Rename helpers to freeze/thaw/restore
Rename the xenbus helpers called from the .freeze, .thaw, and .restore
pm ops to have matching names.

Signed-off-by: Jason Andryuk <jason.andryuk@amd.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Message-ID: <20251119224731.61497-3-jason.andryuk@amd.com>
2026-02-02 07:45:37 +01:00
Jason Andryuk
e08dd1ee49 xenbus: Use .freeze/.thaw to handle xenbus devices
The goal is to fix s2idle and S3 for Xen PV devices.  A domain resuming
from s3 or s2idle disconnects its PV devices during resume.  The
backends are not expecting this and do not reconnect.

b3e96c0c75 ("xen: use freeze/restore/thaw PM events for suspend/
resume/chkpt") changed xen_suspend()/do_suspend() from
PMSG_SUSPEND/PMSG_RESUME to PMSG_FREEZE/PMSG_THAW/PMSG_RESTORE, but the
suspend/resume callbacks remained.

.freeze/restore are used with hiberation where Linux restarts in a new
place in the future.  .suspend/resume are useful for runtime power
management for the duration of a boot.

The current behavior of the callbacks works for an xl save/restore or
live migration where the domain is restored/migrated to a new location
and connecting to a not-already-connected backend.

Change xenbus_pm_ops to use .freeze/thaw/restore and drop the
.suspend/resume hook.  This matches the use in drivers/xen/manage.c for
save/restore and live migration.  With .suspend/resume empty, PV devices
are left connected during s2idle and s3, so PV devices are not changed
and work after resume.

Signed-off-by: Jason Andryuk <jason.andryuk@amd.com>
Acked-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Message-ID: <20251119224731.61497-2-jason.andryuk@amd.com>
2026-02-02 07:45:37 +01:00
Uros Bizjak
c74a1a68a9 xen/mcelog: simplify MCE_GETCLEAR_FLAGS using xchg()
The MCE_GETCLEAR_FLAGS ioctl retrieves xen_mcelog.flags while
atomically clearing it. This was previously implemented using a
cmpxchg() loop.

Replace the cmpxchg() loop with a single xchg(), which provides the
same atomic get-and-clear semantics, avoids retry spinning under
contention, and simplifies the code.

The code on x86_64 improves from:

    186:	8b 15 00 00 00 00    	mov    0x0(%rip),%edx
    18c:	89 d0                	mov    %edx,%eax
    18e:	f0 0f b1 0d 00 00 00 	lock cmpxchg %ecx,0x0(%rip)
    195:	00
    196:	39 c2                	cmp    %eax,%edx
    198:	75 ec                	jne    186 <...>

to just:

    186:	87 05 00 00 00 00    	xchg   %eax,0x0(%rip)

No functional change intended.

Signed-off-by: Uros Bizjak <ubizjak@gmail.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Message-ID: <20260122141754.116129-1-ubizjak@gmail.com>
2026-02-02 07:36:25 +01:00
Roger Pau Monne
b13cd24c15 xen/balloon: improve accuracy of initial balloon target for dom0
The dom0 balloon target set by the toolstack is the value returned by
XENMEM_current_reservation.  Do the same in the kernel balloon driver and
set the current allocation to the value returned by
XENMEM_current_reservation.  On my test system this causes the kernel
balloon driver target to exactly match the value set by the toolstack in
xenstore.

Note this approach can be used by both PV and PVH dom0s, as the toolstack
always uses XENMEM_current_reservation to set the initial target regardless
of the dom0 type.

Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Message-ID: <20260128110510.46425-3-roger.pau@citrix.com>
2026-02-02 07:31:22 +01:00
Roger Pau Monne
0949c646d6 Partial revert "x86/xen: fix balloon target initialization for PVH dom0"
This partially reverts commit 87af633689 so
the current memory target for PV guests is still fetched from
start_info->nr_pages, which matches exactly what the toolstack sets the
initial memory target to.

Using get_num_physpages() is possible on PV also, but needs adjusting to
take into account the ISA hole and the PFN at 0 not considered usable
memory despite being populated, and hence would need extra adjustments.
Instead of carrying those extra adjustments switch back to the previous
code.  That leaves Linux with a difference in how current memory target is
obtained for HVM vs PV, but that's better than adding extra logic just for
PV.

However if switching to start_info->nr_pages for PV domains we need to
differentiate between released pages (freed back to the hypervisor) as
opposed to pages in the physmap which are not populated to start with.
Introduce a new xen_unpopulated_pages to account for papges that have
never been populated, and hence in the PV case don't need subtracting.

Fixes: 87af633689 ("x86/xen: fix balloon target initialization for PVH dom0")
Reported-by: James Dingwall <james@dingwall.me.uk>
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Message-ID: <20260128110510.46425-2-roger.pau@citrix.com>
2026-02-02 07:31:22 +01:00
Linus Torvalds
0237777974 Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull SCSI fixes from James Bottomley:
 "Only one core change, the rest are drivers.

  The core change reorders some state operations in the error handler to
  try to prevent missed wake ups of the error handler (which can halt
  error processing and effectively freeze the entire system)"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  scsi: qla2xxx: Sanitize payload size to prevent member overflow
  scsi: target: iscsi: Fix use-after-free in iscsit_dec_session_usage_count()
  scsi: target: iscsi: Fix use-after-free in iscsit_dec_conn_usage_count()
  scsi: core: Wake up the error handler when final completions race against each other
  scsi: storvsc: Process unsupported MODE_SENSE_10
  scsi: xen: scsiback: Fix potential memory leak in scsiback_remove()
2026-01-25 12:06:15 -08:00
Juergen Gross
589f41f2f0 x86/paravirt: Use common code for paravirt_steal_clock()
Remove the arch-specific variant of paravirt_steal_clock() and use
the common one instead.

With all archs supporting Xen now having been switched to the common
variant, including paravirt.h can be dropped from drivers/xen/time.c.

Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://patch.msgid.link/20260105110520.21356-12-jgross@suse.com
2026-01-12 16:48:26 +01:00
Juergen Gross
15518e633b arm/paravirt: Use common code for paravirt_steal_clock()
Remove the arch-specific variant of paravirt_steal_clock() and use
the common one instead.

This allows to remove paravirt.c and paravirt.h from arch/arm.

Until all archs supporting Xen have been switched to the common code
of paravirt_steal_clock(), drivers/xen/time.c needs to include
asm/paravirt.h for those archs, while this is not necessary for arm
any longer.

Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://patch.msgid.link/20260105110520.21356-8-jgross@suse.com
2026-01-12 15:57:23 +01:00
Juergen Gross
e6b2aa6d40 sched: Move clock related paravirt code to kernel/sched
Paravirt clock related functions are available in multiple archs.

In order to share the common parts, move the common static keys
to kernel/sched/ and remove them from the arch specific files.

Make a common paravirt_steal_clock() implementation available in
kernel/sched/cputime.c, guarding it with a new config option
CONFIG_HAVE_PV_STEAL_CLOCK_GEN, which can be selected by an arch
in case it wants to use that common variant.

Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://patch.msgid.link/20260105110520.21356-7-jgross@suse.com
2026-01-12 15:39:14 +01:00
Teddy Astie
dc8ea87143 xen/virtio: Don't use grant-dma-ops when running as Dom0
Dom0 inherit devices from the machine and is usually in PV mode.
If we are running in a virtual that has virtio devices, these devices
would be considered as using grants with Dom0 as backend, while being
the said Dom0 itself, while we want to use these devices like regular
PCI devices.

Fix this by preventing grant-dma-ops from being used when running as Dom0
(initial domain). We still keep the device-tree logic as-is.

Signed-off-by: Teddy Astie <teddy.astie@vates.tech>
Fixes: 61367688f1 ("xen/virtio: enable grant based virtio on x86")
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Message-ID: <6698564dd2270a9f7377b78ebfb20cb425cabbe8.1767720955.git.teddy.astie@vates.tech>
2026-01-12 13:05:51 +01:00
Marco Crivellari
378f1dc3d6 xen: privcmd: WQ_PERCPU added to alloc_workqueue users
Currently if a user enqueue a work item using schedule_delayed_work() the
used wq is "system_wq" (per-cpu wq) while queue_delayed_work() use
WORK_CPU_UNBOUND (used when a cpu is not specified). The same applies to
schedule_work() that is using system_wq and queue_work(), that makes use
again of WORK_CPU_UNBOUND.
This lack of consistentcy cannot be addressed without refactoring the API.

alloc_workqueue() treats all queues as per-CPU by default, while unbound
workqueues must opt-in via WQ_UNBOUND.

This default is suboptimal: most workloads benefit from unbound queues,
allowing the scheduler to place worker threads where they’re needed and
reducing noise when CPUs are isolated.

This continues the effort to refactor workqueue APIs, which began with
the introduction of new workqueues and a new alloc_workqueue flag in:

commit 128ea9f6cc ("workqueue: Add system_percpu_wq and system_dfl_wq")
commit 930c2ea566 ("workqueue: Add new WQ_PERCPU flag")

This change adds a new WQ_PERCPU flag to explicitly request alloc_workqueue()
to be per-cpu when WQ_UNBOUND has not been specified.

With the introduction of the WQ_PERCPU flag (equivalent to !WQ_UNBOUND),
any alloc_workqueue() caller that doesn’t explicitly specify WQ_UNBOUND
must now use WQ_PERCPU.

Once migration is complete, WQ_UNBOUND can be removed and unbound will
become the implicit default.

Suggested-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Marco Crivellari <marco.crivellari@suse.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Message-ID: <20251106155831.306248-3-marco.crivellari@suse.com>
2026-01-12 11:28:46 +01:00
Marco Crivellari
842df741a4 xen/events: replace use of system_wq with system_percpu_wq
Currently if a user enqueues a work item using schedule_delayed_work() the
used wq is "system_wq" (per-cpu wq) while queue_delayed_work() use
WORK_CPU_UNBOUND (used when a cpu is not specified). The same applies to
schedule_work() that is using system_wq and queue_work(), that makes use
again of WORK_CPU_UNBOUND.

This lack of consistency cannot be addressed without refactoring the API.

This continues the effort to refactor workqueue APIs, which began with
the introduction of new workqueues and a new alloc_workqueue flag in:

commit 128ea9f6cc ("workqueue: Add system_percpu_wq and system_dfl_wq")
commit 930c2ea566 ("workqueue: Add new WQ_PERCPU flag")

Switch to using system_percpu_wq because system_wq is going away as part of
a workqueue restructuring.

Suggested-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Marco Crivellari <marco.crivellari@suse.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Message-ID: <20251106155831.306248-2-marco.crivellari@suse.com>
2026-01-12 11:28:46 +01:00
Abdun Nihaal
901a5f309d scsi: xen: scsiback: Fix potential memory leak in scsiback_remove()
Memory allocated for struct vscsiblk_info in scsiback_probe() is not
freed in scsiback_remove() leading to potential memory leaks on remove,
as well as in the scsiback_probe() error paths. Fix that by freeing it
in scsiback_remove().

Cc: stable@vger.kernel.org
Fixes: d9d660f6e5 ("xen-scsiback: Add Xen PV SCSI backend driver")
Signed-off-by: Abdun Nihaal <nihaal@cse.iitm.ac.in>
Reviewed-by: Juergen Gross <jgross@suse.com>
Link: https://patch.msgid.link/20251223063012.119035-1-nihaal@cse.iitm.ac.in
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2026-01-11 21:35:49 -05:00
Lorenzo Pieralisi
1ca8677d9f ACPI: PCI: IRQ: Fix INTx GSIs signedness
In ACPI Global System Interrupts (GSIs) are described using a 32-bit
value.

ACPI/PCI legacy interrupts (INTx) parsing code treats GSIs as 'int',
which poses issues if the GSI interrupt value is a 32-bit value with the
MSB set (as required in some interrupt configurations - eg ARM64 GICv5
systems) because acpi_pci_link_allocate_irq() treats a negative gsi
return value as a failed GSI allocation (and acpi_irq_get_penalty()
would trigger an out-of-bounds array dereference if the 'irq' param is
a negative value).

Fix ACPI/PCI legacy INTx parsing by converting variables representing
GSIs from 'int' to 'u32' bringing the code in line with the ACPI
specification and fixing the current parsing issue.

Signed-off-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
Reviewed-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://patch.msgid.link/20260105101705.36703-1-lpieralisi@kernel.org
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2026-01-05 19:06:40 +01:00
Linus Torvalds
1a68aefc71 Merge tag 'for-linus-6.19-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull xen updates from Juergen Gross:
 "This round it contains only three small cleanup patches"

* tag 'for-linus-6.19-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  drivers/xen: use min() instead of min_t()
  drivers/xen/xenbus: Replace deprecated strcpy in xenbus_transaction_end
  drivers/xen/xenbus: Simplify return statement in join()
2025-12-06 10:49:19 -08:00
Linus Torvalds
a7405aa92f Merge tag 'dma-mapping-6.19-2025-12-05' of git://git.kernel.org/pub/scm/linux/kernel/git/mszyprowski/linux
Pull dma-mapping updates from Marek Szyprowski:

 - More DMA mapping API refactoring to physical addresses as the primary
   interface instead of page+offset parameters.

   This time dma_map_ops callbacks are converted to physical addresses,
   what in turn results also in some simplification of architecture
   specific code (Leon Romanovsky and Jason Gunthorpe)

 - Clarify that dma_map_benchmark is not a kernel self-test, but
   standalone tool (Qinxin Xia)

* tag 'dma-mapping-6.19-2025-12-05' of git://git.kernel.org/pub/scm/linux/kernel/git/mszyprowski/linux:
  dma-mapping: remove unused map_page callback
  xen: swiotlb: Convert mapping routine to rely on physical address
  x86: Use physical address for DMA mapping
  sparc: Use physical address DMA mapping
  powerpc: Convert to physical address DMA mapping
  parisc: Convert DMA map_page to map_phys interface
  MIPS/jazzdma: Provide physical address directly
  alpha: Convert mapping routine to rely on physical address
  dma-mapping: remove unused mapping resource callbacks
  xen: swiotlb: Switch to physical address mapping callbacks
  ARM: dma-mapping: Switch to physical address mapping callbacks
  ARM: dma-mapping: Reduce struct page exposure in arch_sync_dma*()
  dma-mapping: convert dummy ops to physical address mapping
  dma-mapping: prepare dma_map_ops to conversion to physical address
  tools/dma: move dma_map_benchmark from selftests to tools/dma
2025-12-06 09:25:05 -08:00
Linus Torvalds
208eed95fc Merge tag 'soc-drivers-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc
Pull SoC driver updates from Arnd Bergmann:
 "This is the first half of the driver changes:

   - A treewide interface change to the "syscore" operations for power
     management, as a preparation for future Tegra specific changes

   - Reset controller updates with added drivers for LAN969x, eic770 and
     RZ/G3S SoCs

   - Protection of system controller registers on Renesas and Google
     SoCs, to prevent trivially triggering a system crash from e.g.
     debugfs access

   - soc_device identification updates on Nvidia, Exynos and Mediatek

   - debugfs support in the ST STM32 firewall driver

   - Minor updates for SoC drivers on AMD/Xilinx, Renesas, Allwinner, TI

   - Cleanups for memory controller support on Nvidia and Renesas"

* tag 'soc-drivers-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (114 commits)
  memory: tegra186-emc: Fix missing put_bpmp
  Documentation: reset: Remove reset_controller_add_lookup()
  reset: fix BIT macro reference
  reset: rzg2l-usbphy-ctrl: Fix a NULL vs IS_ERR() bug in probe
  reset: th1520: Support reset controllers in more subsystems
  reset: th1520: Prepare for supporting multiple controllers
  dt-bindings: reset: thead,th1520-reset: Add controllers for more subsys
  dt-bindings: reset: thead,th1520-reset: Remove non-VO-subsystem resets
  reset: remove legacy reset lookup code
  clk: davinci: psc: drop unused reset lookup
  reset: rzg2l-usbphy-ctrl: Add support for RZ/G3S SoC
  reset: rzg2l-usbphy-ctrl: Add support for USB PWRRDY
  dt-bindings: reset: renesas,rzg2l-usbphy-ctrl: Document RZ/G3S support
  reset: eswin: Add eic7700 reset driver
  dt-bindings: reset: eswin: Documentation for eic7700 SoC
  reset: sparx5: add LAN969x support
  dt-bindings: reset: microchip: Add LAN969x support
  soc: rockchip: grf: Add select correct PWM implementation on RK3368
  soc/tegra: pmc: Add USB wake events for Tegra234
  amba: tegra-ahb: Fix device leak on SMMU enable
  ...
2025-12-05 17:29:04 -08:00
Linus Torvalds
7cd122b552 Merge tag 'pull-persistency' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull persistent dentry infrastructure and conversion from Al Viro:
 "Some filesystems use a kinda-sorta controlled dentry refcount leak to
  pin dentries of created objects in dcache (and undo it when removing
  those). A reference is grabbed and not released, but it's not actually
  _stored_ anywhere.

  That works, but it's hard to follow and verify; among other things, we
  have no way to tell _which_ of the increments is intended to be an
  unpaired one. Worse, on removal we need to decide whether the
  reference had already been dropped, which can be non-trivial if that
  removal is on umount and we need to figure out if this dentry is
  pinned due to e.g. unlink() not done. Usually that is handled by using
  kill_litter_super() as ->kill_sb(), but there are open-coded special
  cases of the same (consider e.g. /proc/self).

  Things get simpler if we introduce a new dentry flag
  (DCACHE_PERSISTENT) marking those "leaked" dentries. Having it set
  claims responsibility for +1 in refcount.

  The end result this series is aiming for:

   - get these unbalanced dget() and dput() replaced with new primitives
     that would, in addition to adjusting refcount, set and clear
     persistency flag.

   - instead of having kill_litter_super() mess with removing the
     remaining "leaked" references (e.g. for all tmpfs files that hadn't
     been removed prior to umount), have the regular
     shrink_dcache_for_umount() strip DCACHE_PERSISTENT of all dentries,
     dropping the corresponding reference if it had been set. After that
     kill_litter_super() becomes an equivalent of kill_anon_super().

  Doing that in a single step is not feasible - it would affect too many
  places in too many filesystems. It has to be split into a series.

  This work has really started early in 2024; quite a few preliminary
  pieces have already gone into mainline. This chunk is finally getting
  to the meat of that stuff - infrastructure and most of the conversions
  to it.

  Some pieces are still sitting in the local branches, but the bulk of
  that stuff is here"

* tag 'pull-persistency' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (54 commits)
  d_make_discardable(): warn if given a non-persistent dentry
  kill securityfs_recursive_remove()
  convert securityfs
  get rid of kill_litter_super()
  convert rust_binderfs
  convert nfsctl
  convert rpc_pipefs
  convert hypfs
  hypfs: swich hypfs_create_u64() to returning int
  hypfs: switch hypfs_create_str() to returning int
  hypfs: don't pin dentries twice
  convert gadgetfs
  gadgetfs: switch to simple_remove_by_name()
  convert functionfs
  functionfs: switch to simple_remove_by_name()
  functionfs: fix the open/removal races
  functionfs: need to cancel ->reset_work in ->kill_sb()
  functionfs: don't bother with ffs->ref in ffs_data_{opened,closed}()
  functionfs: don't abuse ffs_data_closed() on fs shutdown
  convert selinuxfs
  ...
2025-12-05 14:36:21 -08:00
David Laight
150215b89b drivers/xen: use min() instead of min_t()
min_t(unsigned int, a, b) casts an 'unsigned long' to 'unsigned int'.
Use min(a, b) instead as it promotes any 'unsigned int' to 'unsigned long'
and so cannot discard significant bits.

In this case the 'unsigned long' value is small enough that the result
is ok.

Detected by an extra check added to min_t().

Signed-off-by: David Laight <david.laight.linux@gmail.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Message-ID: <20251119224140.8616-30-david.laight.linux@gmail.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
2025-12-05 08:46:07 +01:00
Linus Torvalds
8f7aa3d3c7 Merge tag 'net-next-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next
Pull networking updates from Jakub Kicinski:
 "Core & protocols:

   - Replace busylock at the Tx queuing layer with a lockless list.

     Resulting in a 300% (4x) improvement on heavy TX workloads, sending
     twice the number of packets per second, for half the cpu cycles.

   - Allow constantly busy flows to migrate to a more suitable CPU/NIC
     queue.

     Normally we perform queue re-selection when flow comes out of idle,
     but under extreme circumstances the flows may be constantly busy.

     Add sysctl to allow periodic rehashing even if it'd risk packet
     reordering.

   - Optimize the NAPI skb cache, make it larger, use it in more paths.

   - Attempt returning Tx skbs to the originating CPU (like we already
     did for Rx skbs).

   - Various data structure layout and prefetch optimizations from Eric.

   - Remove ktime_get() from the recvmsg() fast path, ktime_get() is
     sadly quite expensive on recent AMD machines.

   - Extend threaded NAPI polling to allow the kthread busy poll for
     packets.

   - Make MPTCP use Rx backlog processing. This lowers the lock
     pressure, improving the Rx performance.

   - Support memcg accounting of MPTCP socket memory.

   - Allow admin to opt sockets out of global protocol memory accounting
     (using a sysctl or BPF-based policy). The global limits are a poor
     fit for modern container workloads, where limits are imposed using
     cgroups.

   - Improve heuristics for when to kick off AF_UNIX garbage collection.

   - Allow users to control TCP SACK compression, and default to 33% of
     RTT.

   - Add tcp_rcvbuf_low_rtt sysctl to let datacenter users avoid
     unnecessarily aggressive rcvbuf growth and overshot when the
     connection RTT is low.

   - Preserve skb metadata space across skb_push / skb_pull operations.

   - Support for IPIP encapsulation in the nftables flowtable offload.

   - Support appending IP interface information to ICMP messages (RFC
     5837).

   - Support setting max record size in TLS (RFC 8449).

   - Remove taking rtnl_lock from RTM_GETNEIGHTBL and RTM_SETNEIGHTBL.

   - Use a dedicated lock (and RCU) in MPLS, instead of rtnl_lock.

   - Let users configure the number of write buffers in SMC.

   - Add new struct sockaddr_unsized for sockaddr of unknown length,
     from Kees.

   - Some conversions away from the crypto_ahash API, from Eric Biggers.

   - Some preparations for slimming down struct page.

   - YAML Netlink protocol spec for WireGuard.

   - Add a tool on top of YAML Netlink specs/lib for reporting commonly
     computed derived statistics and summarized system state.

  Driver API:

   - Add CAN XL support to the CAN Netlink interface.

   - Add uAPI for reporting PHY Mean Square Error (MSE) diagnostics, as
     defined by the OPEN Alliance's "Advanced diagnostic features for
     100BASE-T1 automotive Ethernet PHYs" specification.

   - Add DPLL phase-adjust-gran pin attribute (and implement it in
     zl3073x).

   - Refactor xfrm_input lock to reduce contention when NIC offloads
     IPsec and performs RSS.

   - Add info to devlink params whether the current setting is the
     default or a user override. Allow resetting back to default.

   - Add standard device stats for PSP crypto offload.

   - Leverage DSA frame broadcast to implement simple HSR frame
     duplication for a lot of switches without dedicated HSR offload.

   - Add uAPI defines for 1.6Tbps link modes.

  Device drivers:

   - Add Motorcomm YT921x gigabit Ethernet switch support.

   - Add MUCSE driver for N500/N210 1GbE NIC series.

   - Convert drivers to support dedicated ops for timestamping control,
     and away from the direct IOCTL handling. While at it support GET
     operations for PHY timestamping.

   - Add (and convert most drivers to) a dedicated ethtool callback for
     reading the Rx ring count.

   - Significant refactoring efforts in the STMMAC driver, which
     supports Synopsys turn-key MAC IP integrated into a ton of SoCs.

   - Ethernet high-speed NICs:
      - Broadcom (bnxt):
         - support PPS in/out on all pins
      - Intel (100G, ice, idpf):
         - ice: implement standard ethtool and timestamping stats
         - i40e: support setting the max number of MAC addresses per VF
         - iavf: support RSS of GTP tunnels for 5G and LTE deployments
      - nVidia/Mellanox (mlx5):
         - reduce downtime on interface reconfiguration
         - disable being an XDP redirect target by default (same as
           other drivers) to avoid wasting resources if feature is
           unused
      - Meta (fbnic):
         - add support for Linux-managed PCS on 25G, 50G, and 100G links
      - Wangxun:
         - support Rx descriptor merge, and Tx head writeback
         - support Rx coalescing offload
         - support 25G SPF and 40G QSFP modules

   - Ethernet virtual:
      - Google (gve):
         - allow ethtool to configure rx_buf_len
         - implement XDP HW RX Timestamping support for DQ descriptor
           format
      - Microsoft vNIC (mana):
         - support HW link state events
         - handle hardware recovery events when probing the device

   - Ethernet NICs consumer, and embedded:
      - usbnet: add support for Byte Queue Limits (BQL)
      - AMD (amd-xgbe):
         - add device selftests
      - NXP (enetc):
         - add i.MX94 support
      - Broadcom integrated MACs (bcmgenet, bcmasp):
         - bcmasp: add support for PHY-based Wake-on-LAN
      - Broadcom switches (b53):
         - support port isolation
         - support BCM5389/97/98 and BCM63XX ARL formats
      - Lantiq/MaxLinear switches:
         - support bridge FDB entries on the CPU port
         - use regmap for register access
         - allow user to enable/disable learning
         - support Energy Efficient Ethernet
         - support configuring RMII clock delays
         - add tagging driver for MaxLinear GSW1xx switches
      - Synopsys (stmmac):
         - support using the HW clock in free running mode
         - add Eswin EIC7700 support
         - add Rockchip RK3506 support
         - add Altera Agilex5 support
      - Cadence (macb):
         - cleanup and consolidate descriptor and DMA address handling
         - add EyeQ5 support
      - TI:
         - icssg-prueth: support AF_XDP
      - Airoha access points:
         - add missing Ethernet stats and link state callback
         - add AN7583 support
         - support out-of-order Tx completion processing
      - Power over Ethernet:
         - pd692x0: preserve PSE configuration across reboots
         - add support for TPS23881B devices

   - Ethernet PHYs:
      - Open Alliance OATC14 10BASE-T1S PHY cable diagnostic support
      - Support 50G SerDes and 100G interfaces in Linux-managed PHYs
      - micrel:
         - support for non PTP SKUs of lan8814
         - enable in-band auto-negotiation on lan8814
      - realtek:
         - cable testing support on RTL8224
         - interrupt support on RTL8221B
      - motorcomm: support for PHY LEDs on YT853
      - microchip: support for LAN867X Rev.D0 PHYs w/ SQI and cable diag
      - mscc: support for PHY LED control

   - CAN drivers:
      - m_can: add support for optional reset and system wake up
      - remove can_change_mtu() obsoleted by core handling
      - mcp251xfd: support GPIO controller functionality

   - Bluetooth:
      - add initial support for PASTa

   - WiFi:
      - split ieee80211.h file, it's way too big
      - improvements in VHT radiotap reporting, S1G, Channel Switch
        Announcement handling, rate tracking in mesh networks
      - improve multi-radio monitor mode support, and add a cfg80211
        debugfs interface for it
      - HT action frame handling on 6 GHz
      - initial chanctx work towards NAN
      - MU-MIMO sniffer improvements

   - WiFi drivers:
      - RealTek (rtw89):
         - support USB devices RTL8852AU and RTL8852CU
         - initial work for RTL8922DE
         - improved injection support
      - Intel:
         - iwlwifi: new sniffer API support
      - MediaTek (mt76):
         - WED support for >32-bit DMA
         - airoha NPU support
         - regdomain improvements
         - continued WiFi7/MLO work
      - Qualcomm/Atheros:
         - ath10k: factory test support
         - ath11k: TX power insertion support
         - ath12k: BSS color change support
         - ath12k: statistics improvements
      - brcmfmac: Acer A1 840 tablet quirk
      - rtl8xxxu: 40 MHz connection fixes/support"

* tag 'net-next-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1381 commits)
  net: page_pool: sanitise allocation order
  net: page pool: xa init with destroy on pp init
  net/mlx5e: Support XDP target xmit with dummy program
  net/mlx5e: Update XDP features in switch channels
  selftests/tc-testing: Test CAKE scheduler when enqueue drops packets
  net/sched: sch_cake: Fix incorrect qlen reduction in cake_drop
  wireguard: netlink: generate netlink code
  wireguard: uapi: generate header with ynl-gen
  wireguard: uapi: move flag enums
  wireguard: uapi: move enum wg_cmd
  wireguard: netlink: add YNL specification
  selftests: drv-net: Fix tolerance calculation in devlink_rate_tc_bw.py
  selftests: drv-net: Fix and clarify TC bandwidth split in devlink_rate_tc_bw.py
  selftests: drv-net: Set shell=True for sysfs writes in devlink_rate_tc_bw.py
  selftests: drv-net: Use Iperf3Runner in devlink_rate_tc_bw.py
  selftests: drv-net: introduce Iperf3Runner for measurement use cases
  selftests: drv-net: Add devlink_rate_tc_bw.py to TEST_PROGS
  net: ps3_gelic_net: Use napi_alloc_skb() and napi_gro_receive()
  Documentation: net: dsa: mention simple HSR offload helpers
  Documentation: net: dsa: mention availability of RedBox
  ...
2025-12-03 17:24:33 -08:00
Thorsten Blum
a73d4a0556 drivers/xen/xenbus: Replace deprecated strcpy in xenbus_transaction_end
strcpy() is deprecated; inline the read-only string instead. Fix the
function comment and use bool instead of int while we're at it.

Link: https://github.com/KSPP/linux/issues/88
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Signed-off-by: Juergen Gross <jgross@suse.com>
Message-ID: <20251031112145.103257-2-thorsten.blum@linux.dev>
2025-11-17 08:48:40 +01:00
Thorsten Blum
6fec913ff1 drivers/xen/xenbus: Simplify return statement in join()
Don't unnecessarily negate 'buffer' and simplify the return statement.

Reviewed-by: Jason Andryuk <jason.andryuk@amd.com>
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Signed-off-by: Juergen Gross <jgross@suse.com>
Message-ID: <20251112171410.3140-2-thorsten.blum@linux.dev>
2025-11-17 07:55:10 +01:00
Al Viro
153f99a45a convert xenfs
entirely static tree, populated by simple_fill_super().  Can switch
to kill_anon_super() without any other changes.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2025-11-16 01:35:02 -05:00
Thierry Reding
a97fbc3ee3 syscore: Pass context data to callbacks
Several drivers can benefit from registering per-instance data along
with the syscore operations. To achieve this, move the modifiable fields
out of the syscore_ops structure and into a separate struct syscore that
can be registered with the framework. Add a void * driver data field for
drivers to store contextual data that will be passed to the syscore ops.

Acked-by: Rafael J. Wysocki (Intel) <rafael@kernel.org>
Signed-off-by: Thierry Reding <treding@nvidia.com>
2025-11-14 10:01:52 +01:00
Josh Poimboeuf
0330b7fbbf drivers/xen/xenbus: Fix namespace collision and split() section placement with AutoFDO
When compiling the kernel with -ffunction-sections enabled, the split()
function gets compiled into the .text.split section.  In some cases it
can even be cloned into .text.split.constprop.0 or .text.split.isra.0.

However, .text.split.* is already reserved for use by the Clang
-fsplit-machine-functions flag, which is used by AutoFDO.  That may
place part of a function's code in a .text.split.<func> section.

This naming conflict causes the vmlinux linker script to wrongly place
split() with other .text.split.* code, rather than where it belongs with
regular text.

Fix it by renaming split() to split_strings().

Fixes: 6568f14cb5 ("vmlinux.lds: Exclude .text.startup and .text.exit from TEXT_MAIN")
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: live-patching@vger.kernel.org
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://patch.msgid.link/92a194234a0f757765e275b288bb1a7236c2c35c.1762991150.git.jpoimboe@kernel.org
2025-11-13 08:03:10 +01:00
Kees Cook
85cb0757d7 net: Convert proto_ops connect() callbacks to use sockaddr_unsized
Update all struct proto_ops connect() callback function prototypes from
"struct sockaddr *" to "struct sockaddr_unsized *" to avoid lying to the
compiler about object sizes. Calls into struct proto handlers gain casts
that will be removed in the struct proto conversion patch.

No binary changes expected.

Signed-off-by: Kees Cook <kees@kernel.org>
Link: https://patch.msgid.link/20251104002617.2752303-3-kees@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-11-04 19:10:32 -08:00
Kees Cook
0e50474fa5 net: Convert proto_ops bind() callbacks to use sockaddr_unsized
Update all struct proto_ops bind() callback function prototypes from
"struct sockaddr *" to "struct sockaddr_unsized *" to avoid lying to the
compiler about object sizes. Calls into struct proto handlers gain casts
that will be removed in the struct proto conversion patch.

No binary changes expected.

Signed-off-by: Kees Cook <kees@kernel.org>
Link: https://patch.msgid.link/20251104002617.2752303-2-kees@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-11-04 19:10:32 -08:00
Leon Romanovsky
936a9f0cb1 xen: swiotlb: Convert mapping routine to rely on physical address
Switch to .map_phys callback instead of .map_page.

Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Link: https://lore.kernel.org/r/20251015-remove-map-page-v5-13-3bbfe3a25cdf@kernel.org
2025-10-29 10:27:30 +01:00
Leon Romanovsky
af85de5a9f xen: swiotlb: Switch to physical address mapping callbacks
Combine resource and page mappings routines to one function
and remove .map_resource/.unmap_resource callbacks completely.

Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Link: https://lore.kernel.org/r/20251015-remove-map-page-v5-5-3bbfe3a25cdf@kernel.org
2025-10-29 10:27:30 +01:00
Linus Torvalds
a498d59c46 Merge tag 'dma-mapping-6.18-2025-09-30' of git://git.kernel.org/pub/scm/linux/kernel/git/mszyprowski/linux
Pull dma-mapping updates from Marek Szyprowski:

 - Refactoring of DMA mapping API to physical addresses as the primary
   interface instead of page+offset parameters

   This gets much closer to Matthew Wilcox's long term wish for
   struct-pageless IO to cacheable DRAM and is supporting memdesc
   project which seeks to substantially transform how struct page works.

   An advantage of this approach is the possibility of introducing
   DMA_ATTR_MMIO, which covers existing 'dma_map_resource' flow in the
   common paths, what in turn lets to use recently introduced
   dma_iova_link() API to map PCI P2P MMIO without creating struct page

   Developped by Leon Romanovsky and Jason Gunthorpe

 - Minor clean-up by Petr Tesarik and Qianfeng Rong

* tag 'dma-mapping-6.18-2025-09-30' of git://git.kernel.org/pub/scm/linux/kernel/git/mszyprowski/linux:
  kmsan: fix missed kmsan_handle_dma() signature conversion
  mm/hmm: properly take MMIO path
  mm/hmm: migrate to physical address-based DMA mapping API
  dma-mapping: export new dma_*map_phys() interface
  xen: swiotlb: Open code map_resource callback
  dma-mapping: implement DMA_ATTR_MMIO for dma_(un)map_page_attrs()
  kmsan: convert kmsan_handle_dma to use physical addresses
  dma-mapping: convert dma_direct_*map_page to be phys_addr_t based
  iommu/dma: implement DMA_ATTR_MMIO for iommu_dma_(un)map_phys()
  iommu/dma: rename iommu_dma_*map_page to iommu_dma_*map_phys
  dma-mapping: rename trace_dma_*map_page to trace_dma_*map_phys
  dma-debug: refactor to use physical addresses for page mapping
  iommu/dma: implement DMA_ATTR_MMIO for dma_iova_link().
  dma-mapping: introduce new DMA attribute to indicate MMIO memory
  swiotlb: Remove redundant __GFP_NOWARN
  dma-direct: clean up the logic in __dma_direct_alloc_pages()
2025-10-03 17:41:12 -07:00
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()
  ...
2025-10-02 18:18:33 -07:00
Marek Marczykowski-Górecki
9d52b0b41b xen: take system_transition_mutex on suspend
Xen's do_suspend() calls dpm_suspend_start() without taking required
system_transition_mutex. Since 12ffc3b151 moved the
pm_restrict_gfp_mask() call, not taking that mutex results in a WARN.

Take the mutex in do_suspend(), and use mutex_trylock() to follow
how enter_state() does this.

Suggested-by: Jürgen Groß <jgross@suse.com>
Fixes: 12ffc3b151 "PM: Restrict swap use to later in the suspend sequence"
Link: https://lore.kernel.org/xen-devel/aKiBJeqsYx_4Top5@mail-itl/
Signed-off-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Cc: stable@vger.kernel.org # v6.16+
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Message-ID: <20250921162853.223116-1-marmarek@invisiblethingslab.com>
2025-09-22 10:16:55 +02:00
David Hildenbrand
4c89792ea0 mm: rename vm_ops->find_special_page() to vm_ops->find_normal_page()
...  and hide it behind a kconfig option.  There is really no need for any
!xen code to perform this check.

The naming is a bit off: we want to find the "normal" page when a PTE was
marked "special".  So it's really not "finding a special" page.

Improve the documentation, and add a comment in the code where XEN ends up
performing the pte_mkspecial() through a hypercall.  More details can be
found in commit 923b2919e2 ("xen/gntdev: mark userspace PTEs as special
on x86 PV guests").

Link: https://lkml.kernel.org/r/20250811112631.759341-12-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: Wei Yang <richard.weiyang@gmail.com>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jann Horn <jannh@google.com>
Cc: Juegren Gross <jgross@suse.com>
Cc: Lance Yang <lance.yang@linux.dev>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Mariano Pache <npache@redhat.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-09-13 16:54:53 -07:00
Leon Romanovsky
bf0ecb3c32 xen: swiotlb: Open code map_resource callback
General dma_direct_map_resource() is going to be removed
in next patch, so simply open-code it in xen driver.

Reviewed-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Link: https://lore.kernel.org/r/e9c66a92e818f416875441b6711963f9782dbbeb.1757423202.git.leonro@nvidia.com
2025-09-12 00:18:20 +02:00
Lukas Wunner
f770c3d858 xen/manage: Fix suspend error path
The device power management API has the following asymmetry:
* dpm_suspend_start() does not clean up on failure
  (it requires a call to dpm_resume_end())
* dpm_suspend_end() does clean up on failure
  (it does not require a call to dpm_resume_start())

The asymmetry was introduced by commit d8f3de0d24 ("Suspend-related
patches for 2.6.27") in June 2008:  It removed a call to device_resume()
from device_suspend() (which was later renamed to dpm_suspend_start()).

When Xen began using the device power management API in May 2008 with
commit 0e91398f2a ("xen: implement save/restore"), the asymmetry did
not yet exist.  But since it was introduced, a call to dpm_resume_end()
is missing in the error path of dpm_suspend_start().  Fix it.

Fixes: d8f3de0d24 ("Suspend-related patches for 2.6.27")
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: stable@vger.kernel.org  # v2.6.27
Reviewed-by: "Rafael J. Wysocki (Intel)" <rafael@kernel.org>
Signed-off-by: Juergen Gross <jgross@suse.com>
Message-ID: <22453676d1ddcebbe81641bb68ddf587fee7e21e.1756990799.git.lukas@wunner.de>
2025-09-09 09:10:44 +02:00
Jason Andryuk
3fcc8e1469 xen/events: Update virq_to_irq on migration
VIRQs come in 3 flavors, per-VPU, per-domain, and global, and the VIRQs
are tracked in per-cpu virq_to_irq arrays.

Per-domain and global VIRQs must be bound on CPU 0, and
bind_virq_to_irq() sets the per_cpu virq_to_irq at registration time
Later, the interrupt can migrate, and info->cpu is updated.  When
calling __unbind_from_irq(), the per-cpu virq_to_irq is cleared for a
different cpu.  If bind_virq_to_irq() is called again with CPU 0, the
stale irq is returned.  There won't be any irq_info for the irq, so
things break.

Make xen_rebind_evtchn_to_cpu() update the per_cpu virq_to_irq mappings
to keep them update to date with the current cpu.  This ensures the
correct virq_to_irq is cleared in __unbind_from_irq().

Fixes: e46cdb66c8 ("xen: event channels")
Cc: stable@vger.kernel.org
Signed-off-by: Jason Andryuk <jason.andryuk@amd.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Message-ID: <20250828003604.8949-4-jason.andryuk@amd.com>
2025-09-09 09:09:30 +02:00