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Shutemov" , Yang Shi , David Hildenbrand , Jiaqi Yan , linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: 28DB68001A X-Stat-Signature: fnhbbarnw7858x1o6uyi14miesnq6m3p X-Rspam-User: X-HE-Tag: 1679610518-90637 X-HE-Meta: U2FsdGVkX1/4QMpRqdxy78dfBKOwpBm49/UHgeT7K/rlakSd1AntbRnY57RDh5Xggpwe/W+okU4XRNwyMN73ggEyIHm77HGkw2lK/snARj8Ix2EV5rtDkKOnUNp4D7ETyNJC/qvY4bLX/wAl5FO+lY7G26e0LDqqtHQGwpLXddeN3vs5j9M6u1dSG9FVBIiKzoIJx9U4fdw5Gv8zaORkDsHtoubwAMZqOrCl/YYZo4nyEIXdhRb4GIemzfAd1wK4Hk6v8EgYh7CGwY+CGbUCYt1zK58rN9lrHn0ZsKk44PCSzj4AASRtg0uQdqhXh1frNMWJo9MrWMUCOoKeZxLpzLLTohIklpzSMXMSbKNucjDeoH2cq/GCG05fN8dv0uP0EGcL7r/vzj9Mg4oPktlhHH9UzCQoHQWgxNrk75tn7kGemEfkthY25PIeB5nbggm2fCCD/JEhzaFdfPgl5npbVVuQ/8ThtuLw9JPrhSe9ZOTJXoplGgFZfZQjSB5wMwFXwiOZw6k1ylHpVjbBkYtu5QOBg5t06sEXn/t/B+OaDUM4lbi3gIX7hK0IUIwtNOc3shmKqeZ0lfQ87huA+CTRMFGlmABE/IPe6RW4uUXEbzyZe9kyYKri5d38rUE53KnCG3NW6EyAqjkFQqJNF71TXvigMp3pv860V9CqFX5vTX46ju1mjnHoG7iR70qnZC8SMOCGSz+86Fvz/q6Zqp1r2MZA+8WySlx2HMldaz1kINzLJOzkG4QMubpvKCTLb13ztu9XFCijExYLTWkYIJYPqgnz33kxK4tIPlFreF3nrCkecXwcv0ON/0r9gSF/Ihm/tmcJxRmjmCIhVg7B5M9qp38jxakcsmRDlFvyHUeZZZg0C0PgqRq6201TDfGKyr0tRO0NN02CUuQxg4o/WVkvmiWl0XKQnZuFMquBxnNjtfMHLzaPXxUxkChWuM+rjEYis0duvpWR8nCM6hOSOCJ Cvx8cjDq VDUHrB1Limx810VVeWAE8wu3J9RQbsYZSeOvs9/JD62V0H8aWHmfy9OWzSEItGYnICrppurwi/FzK+9GE7nzewuKV5TWQSWIJEzd6uo5/0kprY/kT8y0EAu59jlmwqxapyLLJ/UeExDlqds2RiZsd2sVUEov+FgbQpvDlmR0P+FRxWtA2fmFPk5DjWmxvxviHmCnqhll6OhCGFgI/Fy+HjtLP0x/ksBpjrtu0Sx9QKlUh9n9SYH5A9U2K4mEuyvQGw8a8Jk1HP9k18BJW6MDBY+HBLSxf8+bbErQo+p37GzCqhM6g+nRCDn7ne1o+kBb0hvILNoVrKw0rUEZK/S+tKgWNeC1uXcJkhp50PllFdF3aydYXL1GgKz2rgrTrrUwV/oqMskAXiZWFA4eDoSCFt6kDPLCEo9bIL+U1uIVxwoUx3l8= 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: On Thu, Mar 23, 2023 at 2:56=E2=80=AFPM Matthew Wilcox wrote: > > On Thu, Mar 23, 2023 at 12:07:46PM -0700, Hugh Dickins wrote: > > On an earlier audit, for different reasons, I did also run across > > lib/buildid.c build_id_parse() using find_get_page() without checking > > PageUptodate() - looks as if it might do the wrong thing if it races > > with khugepaged collapsing text to huge, and should probably have a > > similar fix. > > That shouldn't be using find_get_page(). It should probably use > read_cache_folio() which will actually read in the data if it's not > present in the page cache, and return an ERR_PTR if the data couldn't > be read. build_id_parse() can be called from NMI, so I don't think we can let read_cache_folio() read-in the data. Thanks, Song