![]() If obj_exts allocation failed, slab->obj_exts is set to OBJEXTS_ALLOC_FAIL, But we do not clear it when freeing the slab. Since OBJEXTS_ALLOC_FAIL and MEMCG_DATA_OBJEXTS currently share the same bit position, during the release of the associated folio, a VM_BUG_ON_FOLIO() check in folio_memcg_kmem() is triggered because the OBJEXTS_ALLOC_FAIL flag was not cleared, causing it to be interpreted as a kmem folio (non-slab) with MEMCG_OBJEXTS_DATA flag set, which is invalid because MEMCG_OBJEXTS_DATA is supposed to be set only on slabs. Another problem that predates sharing the OBJEXTS_ALLOC_FAIL and MEMCG_DATA_OBJEXTS bits is that on configurations with is_check_pages_enabled(), the non-cleared bit in page->memcg_data will trigger a free_page_is_bad() failure "page still charged to cgroup" When freeing a slab, we clear slab->obj_exts if the obj_ext array has been successfully allocated. So let's clear it also when the allocation has failed. Fixes: |
||
---|---|---|
Documentation | ||
LICENSES | ||
arch | ||
block | ||
certs | ||
crypto | ||
drivers | ||
fs | ||
include | ||
init | ||
io_uring | ||
ipc | ||
kernel | ||
lib | ||
mm | ||
net | ||
rust | ||
samples | ||
scripts | ||
security | ||
sound | ||
tools | ||
usr | ||
virt | ||
.clang-format | ||
.clippy.toml | ||
.cocciconfig | ||
.editorconfig | ||
.get_maintainer.ignore | ||
.gitattributes | ||
.gitignore | ||
.mailmap | ||
.pylintrc | ||
.rustfmt.toml | ||
COPYING | ||
CREDITS | ||
Kbuild | ||
Kconfig | ||
MAINTAINERS | ||
Makefile | ||
README |
README
Linux kernel ============ There are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. Please read Documentation/admin-guide/README.rst first. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. The formatted documentation can also be read online at: https://www.kernel.org/doc/html/latest/ There are various text files in the Documentation/ subdirectory, several of them using the reStructuredText markup notation. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.