diff mbox series

[v10,12/13] mm: smaps: Report arm64 guarded pages in smaps

Message ID 20200316165055.31179-13-broonie@kernel.org (mailing list archive)
State Mainlined
Commit 424037b77519d1537872442ba144dda1464988d7
Headers show
Series arm64: Branch Target Identification support | expand

Commit Message

Mark Brown March 16, 2020, 4:50 p.m. UTC 
From: Daniel Kiss <daniel.kiss@arm.com>

The arm64 Branch Target Identification support is activated by marking
executable pages as guarded pages.  Report pages mapped this way in
smaps to aid diagnostics.

Signed-off-by: Daniel Kiss <daniel.kiss@arm.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
---
 Documentation/filesystems/proc.txt | 1 +
 fs/proc/task_mmu.c                 | 3 +++
 2 files changed, 4 insertions(+)
diff mbox series

Patch

diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt
index 99ca040e3f90..ed5465d0f435 100644
--- a/Documentation/filesystems/proc.txt
+++ b/Documentation/filesystems/proc.txt
@@ -519,6 +519,7 @@  manner. The codes are the following:
     hg  - huge page advise flag
     nh  - no-huge page advise flag
     mg  - mergable advise flag
+    bt  - arm64 BTI guarded page
 
 Note that there is no guarantee that every flag and associated mnemonic will
 be present in all further kernel releases. Things get changed, the flags may
diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index 3ba9ae83bff5..1e3409c484d1 100644
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -668,6 +668,9 @@  static void show_smap_vma_flags(struct seq_file *m, struct vm_area_struct *vma)
 		[ilog2(VM_ARCH_1)]	= "ar",
 		[ilog2(VM_WIPEONFORK)]	= "wf",
 		[ilog2(VM_DONTDUMP)]	= "dd",
+#ifdef CONFIG_ARM64_BTI
+		[ilog2(VM_ARM64_BTI)]	= "bt",
+#endif
 #ifdef CONFIG_MEM_SOFT_DIRTY
 		[ilog2(VM_SOFTDIRTY)]	= "sd",
 #endif