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| author |   Andrei Vagin <avagin@gmail.com> | 2025-03-24 06:53:26 +0000 |
|---|---|---|
| committer |   Andrew Morton <akpm@linux-foundation.org> | 2025-05-11 17:48:16 -0700 |
| commit | a516403787e08119b70ce8bfff985272ef318a58 (patch) | |
| tree | 5b41ff2b433823e4b4e5a4c2522a1f4479eda532 /Documentation/admin-guide/mm | |
| parent | zsmalloc: cleanup headers includes (diff) | |
| download | wireguard-linux-a516403787e08119b70ce8bfff985272ef318a58.tar.xz wireguard-linux-a516403787e08119b70ce8bfff985272ef318a58.zip | |
fs/proc: extend the PAGEMAP_SCAN ioctl to report guard regions
Patch series "fs/proc: extend the PAGEMAP_SCAN ioctl to report guard
regions", v2.
Introduce the PAGE_IS_GUARD flag in the PAGEMAP_SCAN ioctl to expose
information about guard regions. This allows userspace tools, such as
CRIU, to detect and handle guard regions.
Currently, CRIU utilizes PAGEMAP_SCAN as a more efficient alternative to
parsing /proc/pid/pagemap. Without this change, guard regions are
incorrectly reported as swap-anon regions, leading CRIU to attempt dumping
them and subsequently failing.
The series includes updates to the documentation and selftests to reflect
the new functionality.
This patch (of 3):
Introduce the PAGE_IS_GUARD flag in the PAGEMAP_SCAN ioctl to expose
information about guard regions. This allows userspace tools, such as
CRIU, to detect and handle guard regions.
Link: https://lkml.kernel.org/r/20250324065328.107678-1-avagin@google.com
Link: https://lkml.kernel.org/r/20250324065328.107678-2-avagin@google.com
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'Documentation/admin-guide/mm')
| -rw-r--r-- | Documentation/admin-guide/mm/pagemap.rst | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/Documentation/admin-guide/mm/pagemap.rst b/Documentation/admin-guide/mm/pagemap.rst index afce291649dd..e60e9211fd9b 100644 --- a/Documentation/admin-guide/mm/pagemap.rst +++ b/Documentation/admin-guide/mm/pagemap.rst @@ -250,6 +250,7 @@ Following flags about pages are currently supported: - ``PAGE_IS_PFNZERO`` - Page has zero PFN - ``PAGE_IS_HUGE`` - Page is PMD-mapped THP or Hugetlb backed - ``PAGE_IS_SOFT_DIRTY`` - Page is soft-dirty +- ``PAGE_IS_GUARD`` - Page is a part of a guard region The ``struct pm_scan_arg`` is used as the argument of the IOCTL. |