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Fri, 07 Jul 2023 13:08:40 -0700 (PDT) MIME-Version: 1.0 References: <20230707043211.3682710-1-surenb@google.com> In-Reply-To: From: Suren Baghdasaryan Date: Fri, 7 Jul 2023 20:08:29 +0000 Message-ID: Subject: Re: [PATCH 1/2] mm: lock a vma before stack expansion To: Matthew Wilcox Cc: Markus Elfring , linux-mm@kvack.org, kernel-janitors@vger.kernel.org, kernel-team@android.com, Andrew Morton , LKML , Axel Rasmussen , David Hildenbrand , David Rientjes , Davidlohr Bueso , Greg Thelen , Hugh Dickins , Jann Horn , Jerome Glisse , Johannes Weiner , Laurent Dufour , "Liam R. Howlett" , Lorenzo Stoakes , Michal Hocko , Michel Lespinasse , Pasha Tatashin , Peter Xu , Punit Agrawal , Shakeel Butt , Vlastimil Babka Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Rspamd-Queue-Id: 62F7614000E X-Rspam-User: X-Rspamd-Server: rspam05 X-Stat-Signature: sr73qa3jsw4pce9u14natxs7iky75rcc X-HE-Tag: 1688760521-163979 X-HE-Meta: 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 ZmN7aGRZ IM16Th4BCOSF8L8fmPVFjBO3TuBMo3w14GjzokUI6R5+s9SkqSJyEYGOul0DsMU7vrcLdeH2/cDzneXhniXeL4P1nI7P5WpywWht7f4JACKMTzengWdAl8DfIypp4jRrX3ZuresMHqXwKSrgPPa0fbKNpI/CeUoU1dczhW7D9M+jrdjUUc9QAqFTs7Xgs4vTAe27Pvo1ihdHKZgY5EE1s4cQuJCdLsHt1ZDFGmN94VGXK7GCV8/ozrLaP5DeuFhJT4BZDi5OxKPKUwTjYGwsAN2VPjbZ2fdn351K4q33A/QWwFYFyOkI6Xw1RjNhE+NLgYqODIlKS+CeZVYpbU8GmuUR8Ig== 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, Jul 7, 2023 at 8:03=E2=80=AFPM Matthew Wilcox = wrote: > > On Fri, Jul 07, 2023 at 10:00:42PM +0200, Markus Elfring wrote: > > =E2=80=A6 > > > write-locked to prevent page faults into the VMA being expanded. Add > > > the necessary locking. > > > > 1. Would it a bit nicer to put the second sentence on a separate line > > in such a change description? Maybe. Will do if there is a need to post a v2. > > > > 2. I noticed that you put the address =E2=80=9Cstable@vger.kernel.org= =E2=80=9D > > into the message field =E2=80=9CCc=E2=80=9D. > > Would you like to specify such a hint as a tag? > > > > See also: > > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/t= ree/Documentation/process/submitting-patches.rst?h=3Dv6.4#n264 Yeah, I always forget that :( > > > > 3. How do you think about to add the tag =E2=80=9CFixes=E2=80=9D? I thought about it but was not sure which patch I should list under such tag because the rules for stack expansion changed recently. > > > > 4. Will a cover letter become helpful also for the presented small patc= h series? Not much to say other than "add some missing locking" :) > > Markus, your nitpicking is not useful. Please stop. I'll fix the nits, at least the ones I can, if there is a need for v2.