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From: Zhu Yanjun In-Reply-To: <20250330121718.175815-2-bhe@redhat.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 38B7F160008 X-Stat-Signature: uhhon4xt6oxx98ka5teyxo664imyeyoj X-Rspam-User: X-HE-Tag: 1743363790-980635 X-HE-Meta: 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 yDvzQkxI YEs9hzbunARIYoNceNN3909jMn1FX0ScOkENRorVrK935nosxQHxePnQUa9AcupaDLFm3qrmTc99OgeA85NLlLRJIPJMCUGPua9PwyNVuVPUpb+NoNiyA8YRNWG58j9RIBhfFz+x4n4tLK90XeeU9iRtJvnyO8gL1xyUN5Nfo/c/gho+RCMI6+Nyt2GcGeWAGDTQ4Cyb6IQjXX29W3wGCPueet5z7Lsmtd6yvVE/uV5H+ACgHhsRPTCiHCOokNCkQjSny3Du9Hl+haNpLRGbVl95TKg== 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: 在 2025/3/30 14:17, Baoquan He 写道: > Not like fault_in_writeable() or fault_in_writeable(), in fault_in_readable()? In the above, one of the 2 fault_in_writeable should be fault_in_readable() ? Zhu Yanjun > fault_in_safe_writeable() local variable 'start' is increased page > by page to loop till the whole address range is handled. However, > it mistakenly calcalates the size of handled range with 'uaddr - start'. > > Fix it here. > > Signed-off-by: Baoquan He > --- > mm/gup.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/mm/gup.c b/mm/gup.c > index 855ab860f88b..73777b1de679 100644 > --- a/mm/gup.c > +++ b/mm/gup.c > @@ -2207,8 +2207,8 @@ size_t fault_in_safe_writeable(const char __user *uaddr, size_t size) > } while (start != end); > mmap_read_unlock(mm); > > - if (size > (unsigned long)uaddr - start) > - return size - ((unsigned long)uaddr - start); > + if (size > start - (unsigned long)uaddr) > + return size - (start - (unsigned long)uaddr); > return 0; > } > EXPORT_SYMBOL(fault_in_safe_writeable);