[merged mm-stable] mm-mseal-fix-mseal-documentation-for-32-bit-kernels.patch removed from -mm tree
Andrew Morton <[email protected]>
| Newsgroups | org.kernel.vger.mm-commits |
|---|---|
| Message-ID | <[email protected]> |
The quilt patch titled
Subject: mm/mseal: fix mseal documentation for 32-bit kernels
has been removed from the -mm tree. Its filename was
mm-mseal-fix-mseal-documentation-for-32-bit-kernels.patch
This patch was dropped because it was merged into the mm-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
------------------------------------------------------
From: Leon Hwang <[email protected]>
Subject: mm/mseal: fix mseal documentation for 32-bit kernels
Date: Wed, 15 Jul 2026 21:12:58 +0800
mseal.o is built only for 64-bit kernels, so 32-bit kernels fall back to
sys_ni_syscall() and return -ENOSYS rather than -EPERM.
Drop architecture description in mseal.rst, since the arch feature doc has
the latest state of mseal for each architecture.
Fix the CONFIG_MSEAL_SYSTEM_MAPPINGS typo in init/Kconfig.
Link: https://lore.kernel.org/[email protected]
Signed-off-by: Leon Hwang <[email protected]>
Acked-by: Lance Yang <[email protected]>
Cc: Alice Ryhl <[email protected]>
Cc: Anand Moon <[email protected]>
Cc: Doug Anderson <[email protected]>
Cc: Gary Guo <[email protected]>
Cc: Jann Horn <[email protected]>
Cc: Jonathan Corbet <[email protected]>
Cc: Leon Hwang <[email protected]>
Cc: Liam R. Howlett <[email protected]>
Cc: Lorenzo Stoakes <[email protected]>
Cc: Miguel Ojeda <[email protected]>
Cc: Nathan Chancellor <[email protected]>
Cc: Pedro Falcato <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Randy Dunlap <[email protected]>
Cc: Thomas Weißschuh <[email protected]>
Cc: Vlastimil Babka <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
---
Documentation/userspace-api/mseal.rst | 14 ++++++--------
init/Kconfig | 2 +-
2 files changed, 7 insertions(+), 9 deletions(-)
--- a/Documentation/userspace-api/mseal.rst~mm-mseal-fix-mseal-documentation-for-32-bit-kernels
+++ a/Documentation/userspace-api/mseal.rst
@@ -50,8 +50,8 @@ mseal syscall signature
* The start address (``addr``) is not allocated.
* The end address (``addr`` + ``len``) is not allocated.
* A gap (unallocated memory) between start and end address.
- - **-EPERM**:
- * sealing is supported only on 64-bit CPUs, 32-bit is not supported.
+ - **-ENOSYS**:
+ * The kernel does not implement ``mseal()``.
**Note about error return**:
- For above error cases, users can expect the given memory range is
@@ -62,7 +62,8 @@ mseal syscall signature
memory range could happen. However, those cases should be rare.
**Architecture support**:
- mseal only works on 64-bit CPUs, not 32-bit CPUs.
+ mseal is built only for 64-bit kernels. 32-bit kernels return
+ ``-ENOSYS``.
**Idempotent**:
users can call mseal multiple times. mseal on an already sealed memory
@@ -131,11 +132,11 @@ Use cases
- Chrome browser: protect some security sensitive data structures.
- System mappings:
- The system mappings are created by the kernel and includes vdso, vvar,
+ The system mappings are created by the kernel and include vdso, vvar,
vvar_vclock, vectors (arm compat-mode), sigpage (arm compat-mode), uprobes.
Those system mappings are readonly only or execute only, memory sealing can
- protect them from ever changing to writable or unmmap/remapped as different
+ protect them from ever changing to writable or unmapped/remapped as different
attributes. This is useful to mitigate memory corruption issues where a
corrupted pointer is passed to a memory management system.
@@ -143,9 +144,6 @@ Use cases
the CONFIG_MSEAL_SYSTEM_MAPPINGS seals all system mappings of this
architecture.
- The following architectures currently support this feature: x86-64, arm64,
- loongarch and s390.
-
WARNING: This feature breaks programs which rely on relocating
or unmapping system mappings. Known broken software at the time
of writing includes CHECKPOINT_RESTORE, UML, gVisor, rr. Therefore
--- a/init/Kconfig~mm-mseal-fix-mseal-documentation-for-32-bit-kernels
+++ a/init/Kconfig
@@ -2123,7 +2123,7 @@ config ARCH_SUPPORTS_MSEAL_SYSTEM_MAPPIN
from a kernel perspective.
After the architecture enables this, a distribution can set
- CONFIG_MSEAL_SYSTEM_MAPPING to manage access to the feature.
+ CONFIG_MSEAL_SYSTEM_MAPPINGS to manage access to the feature.
For complete descriptions of memory sealing, please see
Documentation/userspace-api/mseal.rst
_
Patches currently in -mm which might be from [email protected] are