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charset=us-ascii Content-Disposition: inline In-Reply-To: <20251126101952.174467-1-xieyuanbin1@huawei.com> X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 0D0D78000B X-Stat-Signature: u8g7u16fgiymat6uebzidkwjbydnqxzs X-Rspam-User: X-HE-Tag: 1764180640-321292 X-HE-Meta: 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 7c5shlvU Mdb1akD8dE8ZLB2IZaaHrUhhbElG2xg4jG2K93mLenZxhzj8Svv8JVkajemxOrjkUbPJKMVe9134GEGGYB+YDfDN6wsRlJXIFKOSL1lBO1VfmrUOCwF5H/bu7qU2pi1FHQp43H5uPReSfH7778gOnYWyTeaiuOiCPbcrpeagh6VtZ3CocQtPw5HDpiG8pPpoGWDrn4r6O7ZXftxt7Xa4u4a+o51ZbSkx0OAfPgY25Q2x6llGxdpKfYb34GU1IPvha5lncS+sn98E+pbh38OYWaQMdZ42AXNpypESSMApcjZw+YXKIvJr/JNKL3B4NNYhbwJJVQc0VPJMBk29iHOTgItHTfgy6WG5sWKl1YTj/IoI7zYdk7HgKshvJdKA4fSVW2bPpW26YKX6uzjbhpo0fCydAYEDBiRuu2OIphfGgKdUw4A/CtwtZ+2WlcL1bXryrx7QCWHglJJ9JPzaQ7NZpBCIwIwwH/IQGBUcnWJX+y70N2eA= 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 Wed, Nov 26, 2025 at 06:19:52PM +0800, Xie Yuanbin wrote: > When the path is initialized with LOOKUP_RCU flag in path_init(), the > rcu read lock will be acquired. Inside the rcu critical section, > load_unaligned_zeropad() may be called. According to the comments of > load_unaligned_zeropad(), when loading the memory, a page fault may be > triggered in the very unlikely case. > Add pagefault_disable() to handle this situation. Way too costly, IMO. That needs to be dealt with in page fault handler and IIRC arm used to do that; did that get broken at some point?