--- Page flags are now stored per-folio. Change kpageflags to report these per-folio flags where appropriate. Most folio flags are set on the head page, i.e. *folio_flag(page, 0). Only three are set on the second page -- PG_has_hwpoisoned, PG_large_rmappable, and PG_hugetlb. kpageflags doesn't report the first two, and the PG_hugetlb check is handled by calls to PageHuge/PageTransCompound(), so no code changes are required for these flags. mm/memory-failure.c applies PG_HWPoison via SetPageHWPoison(page). This call falls through to the SetPage##uname macro in include/linux/page-flags.h, which sets the corresponding PG_##lname bit on the given page struct. Therefore KPF_HWPOISON must come from page->flags. arch/xtensa/mm/cache.c tests and sets the PG_arch1 bit in both folio->flags and page->flags. So both sources are OR'd into KPF_ARCH. As for arch2 and arch3, Kefeng Wang reported that they appear only as arm64-specific aliases: namely, PG_mte_tagged and PG_mte_lock. Both are applied to page->flags via set_bit() in arch/arm64/include/asm/mte.h. So those must come from page->flags, too. Signed-off-by: Svetly Todorov <svetly.todorov@xxxxxxxxxxxx> Suggested-by: Matthew Wilcox <willy@xxxxxxxxxxxxx> Suggested-by: Gregory Price <gregory.price@xxxxxxxxxxxx> Suggested-by: Kefeng Wang <wangkefeng.wang@xxxxxxxxxx> Link: https://lore.kernel.org/all/20231030180005.2046-1-gregory.price@xxxxxxxxxxxx/ Link: https://80x24.org/lore/linux-mm/20231110033324.2455523-4-wangkefeng.wang@xxxxxxxxxx/ Link: https://80x24.org/lore/linux-mm/438ba640-c205-4034-886e-6a7231f3d210@xxxxxxxxxx/ --- fs/proc/page.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/fs/proc/page.c b/fs/proc/page.c index 195b077c0fac..290470819fa2 100644 --- a/fs/proc/page.c +++ b/fs/proc/page.c @@ -110,6 +110,7 @@ static inline u64 kpf_copy_bit(u64 kflags, int ubit, int kbit) u64 stable_page_flags(struct page *page) { u64 k; + u64 p; u64 u; /* @@ -119,7 +120,8 @@ u64 stable_page_flags(struct page *page) if (!page) return 1 << KPF_NOPAGE; - k = page->flags; + k = *folio_flags(page, 0); + p = page->flags; u = 0; /* @@ -205,7 +207,7 @@ u64 stable_page_flags(struct page *page) u |= kpf_copy_bit(k, KPF_MLOCKED, PG_mlocked); #ifdef CONFIG_MEMORY_FAILURE - u |= kpf_copy_bit(k, KPF_HWPOISON, PG_hwpoison); + u |= kpf_copy_bit(p, KPF_HWPOISON, PG_hwpoison); #endif #ifdef CONFIG_ARCH_USES_PG_UNCACHED @@ -216,11 +218,14 @@ u64 stable_page_flags(struct page *page) u |= kpf_copy_bit(k, KPF_MAPPEDTODISK, PG_mappedtodisk); u |= kpf_copy_bit(k, KPF_PRIVATE, PG_private); u |= kpf_copy_bit(k, KPF_PRIVATE_2, PG_private_2); + u |= kpf_copy_bit(p, KPF_PRIVATE, PG_private); + u |= kpf_copy_bit(p, KPF_PRIVATE_2, PG_private_2); u |= kpf_copy_bit(k, KPF_OWNER_PRIVATE, PG_owner_priv_1); u |= kpf_copy_bit(k, KPF_ARCH, PG_arch_1); + u |= kpf_copy_bit(p, KPF_ARCH, PG_arch_1); #ifdef CONFIG_ARCH_USES_PG_ARCH_X - u |= kpf_copy_bit(k, KPF_ARCH_2, PG_arch_2); - u |= kpf_copy_bit(k, KPF_ARCH_3, PG_arch_3); + u |= kpf_copy_bit(p, KPF_ARCH_2, PG_arch_2); + u |= kpf_copy_bit(p, KPF_ARCH_3, PG_arch_3); #endif return u; --- base-commit: e8f897f4afef0031fe618a8e94127a0934896aba change-id: 20240319-kpageflags-svetly-9faa11b17022 Best regards, -- Svetly Todorov <svetly.todorov@xxxxxxxxxxxx>
