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charset=UTF-8 Content-Transfer-Encoding: 8bit X-Rspamd-Queue-Id: 1EC9E180005 X-Rspam-User: X-Rspamd-Server: rspam05 X-Stat-Signature: 34bzi3hfckm5s55n7zpzno9tyemfyqa7 X-HE-Tag: 1689849352-977028 X-HE-Meta: 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 6w1PwEJb jneMLNrbCkzY74xKsttxBhIQpk8mh76slNmZbcXp3uAmcdne3ryqwdpWhinh5appovL/+1H85HvWCgoMDdSG7J+g2ocB6/LDNb8CASVAiFaSUrXCFbygkDGEEJi5esFpsp4bUY5EQna3Un5kvfi0BGTRwdpWWUiQdFV81 X-Bogosity: Ham, tests=bogofilter, spamicity=0.349028, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Wed, Jul 19, 2023 at 2:16 PM Axel Rasmussen wrote: > > I think perhaps the right thing to do is to have handle_userfault() release > mmap_lock when it returns VM_FAULT_NOPAGE, and to have GUP deal with that > appropriately? But, some investigation is required to be sure that's okay to do > in the other non-GUP ways we can end up in handle_userfault(). See if making kworker special works. --- x/fs/userfaultfd.c +++ y/fs/userfaultfd.c @@ -457,6 +457,8 @@ vm_fault_t handle_userfault(struct vm_fa * close the uffd. */ ret = VM_FAULT_NOPAGE; + if (current->flags & PF_WQ_WORKER) + ret = VM_FAULT_OOM; goto out; } --