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charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: 7539A140006 X-Stat-Signature: zxdm9f9e49ps916mm1cbj8dsjo3n3pqb X-Rspam-User: X-HE-Tag: 1788445136-145279 X-HE-Meta: U2FsdGVkX1+yZKQASnN2+be+3U9YSf2q+hu3tM6HR3p9pyIo5vlC3K7MF5BFYoAfbS/42RdSLM7u5bZcYrsq39emDpz/0UTnODP4FaIb1fo+h99WqgB+6aF4SA4faM2+Znr6CtCUeRnstfiDrFXTH2FI90kf9vUxlDAnpo10GopdPiP1iWC+oeBy3DedRTa39ZbUnwu1S61UQuLvjmwML2ZLzXIGn/oDN2VEJ9u+qOaC0slqi74UgmR9m2OopmHG6t/TTEAl+8RQXjLtrY2qEvG4KDxogJ2WJEXka1c3c54hatl+Q0W/eOxtguPpPfVATnTrZWu4oqyPLAberJM8YYZY4DgasnBUaXJWfjWaPt+cOboY2vPLMUh42TdtmckVMAH75rqvcTHDub4KFoOP2Z6obkkGWFFtqI3zqjX+UyefwspXytsO0421oFlx3xI7YD1xkdny3TS/ZPHSXmN1RSlVo+Z/Moo9Fd1OIjxWL9hTnVUiSiynrCImKDpWc0vEHtp0twsXCIfD7jtKB4HA1bitleG4yrHR+wjDwl0Qr8rWrXoyt33o5fCVk/GZxfHtaNfNb+FmVpJkiTo7rGAEZZFkDuXBzUWGS69cQvFQfYyr6oZ/7Ue8P18krBYyCXW5qdFtyPppeFcML/9wnSxFr46ZgSHs2mY0T8sM89w4sx/A5jlanC+3KtaPZMh8pK3+uLslp7oveEpLhW8nv3mkUO/WPmLIjPGTNEjFgj4Hoc46Cn3RpLD7sfd0CY4XBcEkHITnsIWct009eGSaNA8NKojncJWTCdDQ5Lgobps75N2ZRWpWzDYQXy8xKuZiVkgGCvpXx6U67TSJXEGZqYa7uFWXeP3s1lTnfpjHgVIkxNcj5WJijyO6yeovR7H8T60rUloyOptCa/UfdeHbgZKLqEw2pj7dn/eh/r5NegJIvzozhWQ3f3HHa0FblipZeM0N1awbUDw8a+riJYtNFzq As3mg1c9 kPwV92eP9H7SPUY0Y17vjheyQQyXEFbvhnM5sasf9AWO4xKahep4BlA7pOCAgviuqp/z86W/AQRH5vnO8x3S+SIg5rYElo697G1mV5FXHZtVI4DkZIgkQqPtG3nvvGh9l3X7oVJmsRGY3H7wkOVcGFyYIaVHfGs1iVuvd1sksMTdU4gwpGPrz4CNjvojR011AUuQaevBGl/izY0TKXICBMsTaasAu+Du/yexaSkERItLy1CEdEdS0CnMO9UEm1eMMfzW8aZYZVBOQH3D6p30lCP7hIu8A16IbncHWroz4mt0MxWa0n2LpyTkSexo2hhNYiYSwDH0UT0m4BkzqzMnKQ8fPjdpbVDsnZwtbBDNrqgtylJKZGFikOBP4w6oiHNybDaYgfkDPil+JXQZfnyrGSAqPy0+560uHen8j Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 9/3/26 04:54, Kiryl Shutsemau wrote: >> Closes: https://lore.kernel.org/r/CAJxLxMUGu1-L+O_nAONOwOXnS=cNbNApCWqdthRjd76LThtSPg@mail.gmail.com/ >> Fixes: bb3aadf7d446 ("x86/mm: Start actually marking _PAGE_SAVED_DIRTY") > Hm. I don't understand why would this commit explicitly exclude > _PAGE_DIRTY from the mask: > > - val &= _HPAGE_CHG_MASK; > + val &= (_HPAGE_CHG_MASK & ~_PAGE_DIRTY); > > Rick, could you comment? It doesn't look like a typo. My guess is that it's some remnant from an earlier version of the patch. The asymmetry with pte_modify() vs. pmd_modify() just can't be explained any other way. It _might_ have been some attempt to say, "Hey _PAGE_DIRTY is now a part of the pgprot_t since it's part of the 'permissions' of a shadow stack PTE" that got abandoned. But I don't see anything wrong with the fix at all. It does give me pause that this has been losing user data for so long, but it must just be a weird combination of features that few folks use together (huge pages + MADV_FREE).