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charset=us-ascii Content-Disposition: inline In-Reply-To: X-Stat-Signature: pzspnouir839rmwh3tm8115nfg55sutt X-Rspamd-Queue-Id: E56C64000D X-Rspam-User: X-Rspamd-Server: rspam08 X-HE-Tag: 1728069138-828260 X-HE-Meta: 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 NJKbbOM9 Ebh9HXjYqzuWRLF1EuglVFGGMxEIFiEDJ2q7Kle8IhivYEV1gvoly8kCmdOobGdwYveupx1uYWA+aCaVStSbhg/KBFyjXYb/Ez4B56QMb0METn4zkDr6VviYqH6e17iMiX03QgVmuoWPDKUO/ZghjRKitMmP6ftusvyXQdUy+jYjQaJRxo/6mdw4sBfoFHHAQ+Pjy32CJgvRybQ8IVLTN7jQN6tElBZG4yJbfVWJtGaqeiTyqtPmWAx1uyunMofSFfn6Mv4gtiUSf63zFm+ymTIrYtgA/2wUjVQ4qlYOeTXX/C3g8v2dfHYsTJw7SbwFEFxgu6d9FPRdFZ+nyfePYWi5enDCGGFr/pSBV X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Fri, Oct 04, 2024 at 03:09:22PM +0200, Miguel Ojeda wrote: > Hi Matthew, > > I noticed riscv64 defconfig seems to reproducibly hit > `VM_BUG_ON_PAGE(PageAnonNotKsm(page))` in today's next-20241004 -- > please see below. > > I hope that helps! I can also reproduce this on arm64 with CONFIG_DEBUG_VM_PGFLAGS=y. Looks like an invert logic bug from: https://lore.kernel.org/linux-mm/20241002152533.1350629-5-willy@infradead.org/ I made the below changes and the problem goes away. Best regards, Nam diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h index fe9abdf26ab0..ccf3c78faefc 100644 --- a/include/linux/page-flags.h +++ b/include/linux/page-flags.h @@ -1131,14 +1131,14 @@ static __always_inline int PageAnonExclusive(const struct page *page) static __always_inline void SetPageAnonExclusive(struct page *page) { - VM_BUG_ON_PGFLAGS(PageAnonNotKsm(page), page); + VM_BUG_ON_PGFLAGS(!PageAnonNotKsm(page), page); VM_BUG_ON_PGFLAGS(PageHuge(page) && !PageHead(page), page); set_bit(PG_anon_exclusive, &PF_ANY(page, 1)->flags); } static __always_inline void ClearPageAnonExclusive(struct page *page) { - VM_BUG_ON_PGFLAGS(PageAnonNotKsm(page), page); + VM_BUG_ON_PGFLAGS(!PageAnonNotKsm(page), page); VM_BUG_ON_PGFLAGS(PageHuge(page) && !PageHead(page), page); clear_bit(PG_anon_exclusive, &PF_ANY(page, 1)->flags); }