From 424037b77519d1537872442ba144dda1464988d7 Mon Sep 17 00:00:00 2001 From: Daniel Kiss Date: Mon, 16 Mar 2020 16:50:54 +0000 Subject: [PATCH] mm: smaps: Report arm64 guarded pages in smaps 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: Mark Brown Signed-off-by: Daniel Kiss Reviewed-by: Kees Cook Signed-off-by: Catalin Marinas --- Documentation/filesystems/proc.txt | 1 + fs/proc/task_mmu.c | 3 +++ 2 files changed, 4 insertions(+) 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