On Wed, Mar 11, 2020 at 07:26:07PM +0000, Mark Brown wrote: > From: Daniel Kiss <daniel.kiss@xxxxxxx> > > 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@xxxxxxx> Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx> -Kees > Signed-off-by: Mark Brown <broonie@xxxxxxxxxx> > --- > 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 > -- > 2.20.1 > -- Kees Cook
