[PATCH v10 12/40] mm: Define VM_SHADOW_STACK for arm64 when we support GCS
From: Mark Brown <broonie@kernel.org>
Date: 2024-08-01 12:58:42
Also in:
kvmarm, linux-arch, linux-arm-kernel, linux-fsdevel, linux-kselftest, linux-mm, linux-riscv, lkml
Subsystem:
documentation, memory management - core, proc filesystem, the rest · Maintainers:
Jonathan Corbet, Andrew Morton, David Hildenbrand, Linus Torvalds
Use VM_HIGH_ARCH_5 for guarded control stack pages. Reviewed-by: Thiago Jung Bauermann <redacted> Signed-off-by: Mark Brown <broonie@kernel.org> --- Documentation/filesystems/proc.rst | 2 +- include/linux/mm.h | 12 +++++++++++- 2 files changed, 12 insertions(+), 2 deletions(-)
diff --git a/Documentation/filesystems/proc.rst b/Documentation/filesystems/proc.rst
index e834779d9611..6a882c57a7e7 100644
--- a/Documentation/filesystems/proc.rst
+++ b/Documentation/filesystems/proc.rst@@ -579,7 +579,7 @@ encoded manner. The codes are the following: mt arm64 MTE allocation tags are enabled um userfaultfd missing tracking uw userfaultfd wr-protect tracking - ss shadow stack page + ss shadow/guarded control stack page sl sealed == =======================================
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 96faf26b6083..c6c7454ce4e0 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h@@ -353,7 +353,17 @@ extern unsigned int kobjsize(const void *objp); * for more details on the guard size. */ # define VM_SHADOW_STACK VM_HIGH_ARCH_5 -#else +#endif + +#if defined(CONFIG_ARM64_GCS) +/* + * arm64's Guarded Control Stack implements similar functionality and + * has similar constraints to shadow stacks. + */ +# define VM_SHADOW_STACK VM_HIGH_ARCH_5 +#endif + +#ifndef VM_SHADOW_STACK # define VM_SHADOW_STACK VM_NONE #endif
--
2.39.2