On Fri, 22 Jul 2022 02:50:29 +0100, Peter Collingbourne <pcc@xxxxxxxxxx> wrote: > > As with PG_arch_2, this flag is only allowed on 64-bit architectures due > to the shortage of bits available. It will be used by the arm64 MTE code > in subsequent patches. > > Signed-off-by: Peter Collingbourne <pcc@xxxxxxxxxx> > Cc: Will Deacon <will@xxxxxxxxxx> > Cc: Marc Zyngier <maz@xxxxxxxxxx> > Cc: Steven Price <steven.price@xxxxxxx> > [catalin.marinas@xxxxxxx: added flag preserving in __split_huge_page_tail()] > Signed-off-by: Catalin Marinas <catalin.marinas@xxxxxxx> > --- > fs/proc/page.c | 1 + > include/linux/page-flags.h | 1 + > include/trace/events/mmflags.h | 7 ++++--- > mm/huge_memory.c | 1 + > 4 files changed, 7 insertions(+), 3 deletions(-) > > diff --git a/fs/proc/page.c b/fs/proc/page.c > index a2873a617ae8..438b8aa7249d 100644 > --- a/fs/proc/page.c > +++ b/fs/proc/page.c > @@ -220,6 +220,7 @@ u64 stable_page_flags(struct page *page) > u |= kpf_copy_bit(k, KPF_ARCH, PG_arch_1); > #ifdef CONFIG_64BIT > u |= kpf_copy_bit(k, KPF_ARCH_2, PG_arch_2); > + u |= kpf_copy_bit(k, KPF_ARCH_2, PG_arch_3); Are PG_arch_2 and PG_arch_3 supposed to share the same user bit in /proc/kpageflags? This seems odd. M. -- Without deviation from the norm, progress is not possible.
