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[184.144.111.238]) by smtp.gmail.com with ESMTPSA id x28sm1720510qtm.71.2021.07.27.09.37.29 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 27 Jul 2021 09:37:29 -0700 (PDT) Date: Tue, 27 Jul 2021 12:37:28 -0400 From: Peter Xu To: Axel Rasmussen Cc: Andrea Arcangeli , Andrew Morton , Hugh Dickins , Mike Kravetz , linux-kernel@vger.kernel.org, linux-man@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH v2] ioctl_userfaultfd.2, userfaultfd.2: add minor fault mode Message-ID: References: <20210604195622.1249588-1-axelrasmussen@google.com> MIME-Version: 1.0 In-Reply-To: <20210604195622.1249588-1-axelrasmussen@google.com> X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Disposition: inline X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: 74E76E002112 Authentication-Results: imf30.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=d8QMG8Y2; dmarc=pass (policy=none) header.from=redhat.com; spf=none (imf30.hostedemail.com: domain of peterx@redhat.com has no SPF policy when checking 216.205.24.124) smtp.mailfrom=peterx@redhat.com X-Stat-Signature: fkpa7wmkt8m8mwhjewecxwd1h851bb5r X-HE-Tag: 1627403853-273951 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 Fri, Jun 04, 2021 at 12:56:22PM -0700, Axel Rasmussen wrote: > Userfaultfd minor fault mode is supported starting from Linux 5.13. > > This commit adds a description of the new mode, as well as the new ioctl > used to resolve such faults. The two go hand-in-hand: one can't resolve > a minor fault without continue, and continue can't be used to resolve > any other kind of fault. > > This patch covers just the hugetlbfs implementation (in 5.13). Support > for shmem is forthcoming, but as it has not yet made it into a kernel > release candidate, it will be added in a future commit. > > Signed-off-by: Axel Rasmussen FWIW: Reviewed-by: Peter Xu -- Peter Xu