Linux kernel source tree
Go to file
Ryan Roberts a32bf5bb79 selftests/mm: set allocated memory to non-zero content in cow test
After commit b1f202060a ("mm: remap unused subpages to shared zeropage
when splitting isolated thp"), cow test cases involving swapping out THPs
via madvise(MADV_PAGEOUT) started to be skipped due to the subsequent
check via pagemap determining that the memory was not actually swapped
out.  Logs similar to this were emitted:

   ...

   # [RUN] Basic COW after fork() ... with swapped-out, PTE-mapped THP (16 kB)
   ok 2 # SKIP MADV_PAGEOUT did not work, is swap enabled?
   # [RUN] Basic COW after fork() ... with single PTE of swapped-out THP (16 kB)
   ok 3 # SKIP MADV_PAGEOUT did not work, is swap enabled?
   # [RUN] Basic COW after fork() ... with swapped-out, PTE-mapped THP (32 kB)
   ok 4 # SKIP MADV_PAGEOUT did not work, is swap enabled?

   ...

The commit in question introduces the behaviour of scanning THPs and if
their content is predominantly zero, it splits them and replaces the pages
which are wholly zero with the zero page.  These cow test cases were
getting caught up in this.

So let's avoid that by filling the contents of all allocated memory with
a non-zero value. With this in place, the tests are passing again.

Link: https://lkml.kernel.org/r/20250107142555.1870101-1-ryan.roberts@arm.com
Fixes: b1f202060a ("mm: remap unused subpages to shared zeropage when splitting isolated thp")
Signed-off-by: Ryan Roberts <ryan.roberts@arm.com>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Usama Arif <usamaarif642@gmail.com>
Cc: Yu Zhao <yuzhao@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-01-12 19:03:37 -08:00
arch x86/execmem: fix ROX cache usage in Xen PV guests 2025-01-12 19:03:35 -08:00
block block: avoid to reuse hctx not removed from cpuhp callback list 2024-12-18 07:25:37 -07:00
certs sign-file,extract-cert: use pkcs11 provider for OPENSSL MAJOR >= 3 2024-09-20 19:52:48 +03:00
crypto crypto: rsassa-pkcs1 - Copy source data for SG list 2024-12-10 13:34:05 +08:00
Documentation 25 hotfixes. 16 are cc:stable. 18 are MM and 7 are non-MM. 2025-01-05 10:37:45 -08:00
drivers A randconfig build fix and a performance fix: 2025-01-05 10:28:34 -08:00
fs 25 hotfixes. 16 are cc:stable. 18 are MM and 7 are non-MM. 2025-01-05 10:37:45 -08:00
include mm: clear uffd-wp PTE/PMD state on mremap() 2025-01-12 19:03:37 -08:00
init - The series "resource: A couple of cleanups" from Andy Shevchenko 2024-11-25 16:09:48 -08:00
io_uring io_uring/kbuf: use pre-committed buffer address for non-pollable file 2025-01-03 09:38:37 -07:00
ipc - The series "resource: A couple of cleanups" from Andy Shevchenko 2024-11-25 16:09:48 -08:00
kernel 25 hotfixes. 16 are cc:stable. 18 are MM and 7 are non-MM. 2025-01-05 10:37:45 -08:00
lib maple_tree: reload mas before the second call for mas_empty_area 2024-12-30 17:59:07 -08:00
LICENSES LICENSES: add 0BSD license text 2024-09-01 20:43:24 -07:00
mm mm: clear uffd-wp PTE/PMD state on mremap() 2025-01-12 19:03:37 -08:00
net Nothing major here. Over the last two weeks we gathered only around 2025-01-03 14:36:54 -08:00
rust workqueue: Fixes for v6.13-rc5 2025-01-03 15:03:56 -08:00
samples BPF fixes: 2024-12-06 15:07:48 -08:00
scripts scripts/decode_stacktrace.sh: fix decoding of lines with an additional info 2025-01-12 19:03:34 -08:00
security selinux/stable-6.13 PR 20241217 2024-12-18 12:10:15 -08:00
sound sound fixes for 6.13-rc6 2025-01-03 10:54:51 -08:00
tools selftests/mm: set allocated memory to non-zero content in cow test 2025-01-12 19:03:37 -08:00
usr kbuild: Drop support for include/asm-<arch> in headers_check.pl 2024-12-21 11:43:17 +09:00
virt VFIO updates for v6.13 2024-11-27 12:57:03 -08:00
.clang-format clang-format: Update with v6.11-rc1's for_each macro list 2024-08-02 13:20:31 +02:00
.clippy.toml rust: enable Clippy's check-private-items 2024-10-07 21:39:57 +02:00
.cocciconfig
.editorconfig .editorconfig: remove trim_trailing_whitespace option 2024-06-13 16:47:52 +02:00
.get_maintainer.ignore MAINTAINERS: Retire Ralf Baechle 2024-11-12 15:48:59 +01:00
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore Kbuild updates for v6.13 2024-11-30 13:41:50 -08:00
.mailmap mailmap: modify the entry for Mathieu Othacehe 2024-12-30 17:59:08 -08:00
.rustfmt.toml rust: add .rustfmt.toml 2022-09-28 09:02:20 +02:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS cgroup: Changes for v6.13 2024-11-20 09:54:49 -08:00
Kbuild Kbuild updates for v6.1 2022-10-10 12:00:45 -07:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS 25 hotfixes. 16 are cc:stable. 18 are MM and 7 are non-MM. 2025-01-05 10:37:45 -08:00
Makefile Linux 6.13-rc6 2025-01-05 14:13:40 -08:00
README README: Fix spelling 2024-03-18 03:36:32 -06:00

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.