Message ID | 20220722015034.809663-4-pcc@google.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Series | KVM: arm64: permit MAP_SHARED mappings with MTE enabled | expand |
On Fri, 22 Jul 2022 02:50:29 +0100, Peter Collingbourne <pcc@google.com> 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@google.com> > Cc: Will Deacon <will@kernel.org> > Cc: Marc Zyngier <maz@kernel.org> > Cc: Steven Price <steven.price@arm.com> > [catalin.marinas@arm.com: added flag preserving in __split_huge_page_tail()] > Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> > --- > 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.
On Fri, Jul 22, 2022 at 03:16:34PM +0100, Marc Zyngier wrote: > On Fri, 22 Jul 2022 02:50:29 +0100, > Peter Collingbourne <pcc@google.com> 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@google.com> > > Cc: Will Deacon <will@kernel.org> > > Cc: Marc Zyngier <maz@kernel.org> > > Cc: Steven Price <steven.price@arm.com> > > [catalin.marinas@arm.com: added flag preserving in __split_huge_page_tail()] > > Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> > > --- > > 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. No, that was an oversight, thanks for the catch. I will fix it up like so in v3. Peter diff --git a/fs/proc/page.c b/fs/proc/page.c index 438b8aa7249d..0129aa3cfb7a 100644 --- a/fs/proc/page.c +++ b/fs/proc/page.c @@ -220,7 +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); + u |= kpf_copy_bit(k, KPF_ARCH_3, PG_arch_3); #endif return u; diff --git a/include/linux/kernel-page-flags.h b/include/linux/kernel-page-flags.h index eee1877a354e..859f4b0c1b2b 100644 --- a/include/linux/kernel-page-flags.h +++ b/include/linux/kernel-page-flags.h @@ -18,5 +18,6 @@ #define KPF_UNCACHED 39 #define KPF_SOFTDIRTY 40 #define KPF_ARCH_2 41 +#define KPF_ARCH_3 42 #endif /* LINUX_KERNEL_PAGE_FLAGS_H */ diff --git a/tools/vm/page-types.c b/tools/vm/page-types.c index 381dcc00cb62..364373f5bba0 100644 --- a/tools/vm/page-types.c +++ b/tools/vm/page-types.c @@ -79,6 +79,7 @@ #define KPF_UNCACHED 39 #define KPF_SOFTDIRTY 40 #define KPF_ARCH_2 41 +#define KPF_ARCH_3 42 /* [47-] take some arbitrary free slots for expanding overloaded flags * not part of kernel API @@ -138,6 +139,7 @@ static const char * const page_flag_names[] = { [KPF_UNCACHED] = "c:uncached", [KPF_SOFTDIRTY] = "f:softdirty", [KPF_ARCH_2] = "H:arch_2", + [KPF_ARCH_3] = "H:arch_3", [KPF_ANON_EXCLUSIVE] = "d:anon_exclusive", [KPF_READAHEAD] = "I:readahead",
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); #endif return u; diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h index 465ff35a8c00..ad01a3abf6c8 100644 --- a/include/linux/page-flags.h +++ b/include/linux/page-flags.h @@ -134,6 +134,7 @@ enum pageflags { #endif #ifdef CONFIG_64BIT PG_arch_2, + PG_arch_3, #endif #ifdef CONFIG_KASAN_HW_TAGS PG_skip_kasan_poison, diff --git a/include/trace/events/mmflags.h b/include/trace/events/mmflags.h index 11524cda4a95..704380179986 100644 --- a/include/trace/events/mmflags.h +++ b/include/trace/events/mmflags.h @@ -91,9 +91,9 @@ #endif #ifdef CONFIG_64BIT -#define IF_HAVE_PG_ARCH_2(flag,string) ,{1UL << flag, string} +#define IF_HAVE_PG_ARCH_2_3(flag,string) ,{1UL << flag, string} #else -#define IF_HAVE_PG_ARCH_2(flag,string) +#define IF_HAVE_PG_ARCH_2_3(flag,string) #endif #ifdef CONFIG_KASAN_HW_TAGS @@ -129,7 +129,8 @@ IF_HAVE_PG_UNCACHED(PG_uncached, "uncached" ) \ IF_HAVE_PG_HWPOISON(PG_hwpoison, "hwpoison" ) \ IF_HAVE_PG_IDLE(PG_young, "young" ) \ IF_HAVE_PG_IDLE(PG_idle, "idle" ) \ -IF_HAVE_PG_ARCH_2(PG_arch_2, "arch_2" ) \ +IF_HAVE_PG_ARCH_2_3(PG_arch_2, "arch_2" ) \ +IF_HAVE_PG_ARCH_2_3(PG_arch_3, "arch_3" ) \ IF_HAVE_PG_SKIP_KASAN_POISON(PG_skip_kasan_poison, "skip_kasan_poison") #define show_page_flags(flags) \ diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 8320874901f1..d6e8789e9ebb 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -2399,6 +2399,7 @@ static void __split_huge_page_tail(struct page *head, int tail, (1L << PG_unevictable) | #ifdef CONFIG_64BIT (1L << PG_arch_2) | + (1L << PG_arch_3) | #endif (1L << PG_dirty)));