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charset=utf-8 Content-Disposition: inline X-Rspam-User: X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: 2F5F8A001C X-Stat-Signature: equ9wijgwred1m5m1kqoc8j5qetttoes X-HE-Tag: 1704246918-713174 X-HE-Meta: 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 ZBpm6i5N 3URAJGfYaDv8UONVXWMPTSCX9PA5hBefe6FlWXB9KLnwWMuwFYvJOv40DwaJc7L3oGiQFGa00M2m/hX50NU7G1+dMOEy0HXPLCzfBQ5bqp0fhjCwScTQjzptwzZRTzDtsSgHMbVrNc3OR43AJFSJwnCSZ+ZRw9M2B2JSdiV3V1s/l/AHuqa4xdxDw5+oVEdviMsW2OD83bE0EcpVtaiqvu9wo+j7PmMV1sl4rWTXeQ0AA/IWWx5kzcebCJM23Tl/l4Us72RJ+XwHejiF5W8MLtKmccXvRGAE3qIxFpMt5323YwqKXhh9d3Br1zRPXFRGIsk5E5ONWZZjgyrInrLX+3k7Hmyg6thzkRGFwuaRhqbCmQONW3m3qy3D08oUGM4bbx2PwUSKOUgGhRQHuAjXCyKTquh6j20g/ERw7FYFEXbodCs+N2X8ASg0Q545seoEGqZwmRKtM7U54Lhg= 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 Tue, Jan 02, 2024 at 03:32:56PM -0800, Suren Baghdasaryan wrote: > While testing the split PMD path with lockdep enabled I've got an > "Invalid wait context" error caused by split_huge_page_to_list() trying > to lock anon_vma->rwsem while inside RCU read section. The issues is due > to move_pages_pte() calling split_folio() under RCU read lock. Fix this > by unmapping the PTEs and exiting RCU read section before splitting the > folio and then retrying. The same retry pattern is used when locking the > folio or anon_vma in this function. After splitting the large folio we > unlock and release it because after the split the old folio might not be > the one that contains the src_addr. > > Fixes: 94b01c885131 ("userfaultfd: UFFDIO_MOVE uABI") > Signed-off-by: Suren Baghdasaryan Reviewed-by: Peter Xu Thanks, -- Peter Xu