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Wed, 07 Apr 2021 14:54:00 -0700 (PDT) MIME-Version: 1.0 References: <20210401181741.168763-1-surenb@google.com> In-Reply-To: From: Suren Baghdasaryan Date: Wed, 7 Apr 2021 14:53:49 -0700 Message-ID: Subject: Re: [PATCH 0/5] 4.14 backports of fixes for "CoW after fork() issue" To: Linus Torvalds Cc: Mikulas Patocka , Vlastimil Babka , Peter Xu , stable , Greg Kroah-Hartman , Jann Horn , Kirill Tkhai , Shaohua Li , Nadav Amit , Linux-MM , Linux Kernel Mailing List , Android Kernel Team , Andrea Arcangeli , David Hildenbrand , Jason Gunthorpe Content-Type: text/plain; charset="UTF-8" X-Rspamd-Server: rspam01 X-Rspamd-Queue-Id: 10FEBC0007C1 X-Stat-Signature: 9rw5zux5uewsdrtc4dooemijwnahgiw5 Received-SPF: none (google.com>: No applicable sender policy available) receiver=imf06; identity=mailfrom; envelope-from=""; helo=mail-yb1-f171.google.com; client-ip=209.85.219.171 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1617832441-195096 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 Wed, Apr 7, 2021 at 12:23 PM Linus Torvalds wrote: > > On Wed, Apr 7, 2021 at 11:47 AM Mikulas Patocka wrote: > > > > So, we fixed it, but we don't know why. > > > > Peter Xu's patchset that fixed it is here: > > https://lore.kernel.org/lkml/20200821234958.7896-1-peterx@redhat.com/ > > Yeah, that's the part that ends up being really painful to backport > (with all the subsequent fixes too), so the 4.14 people would prefer > to avoid it. > > But I think that if it's a "requires dax pmem and ptrace on top", it > may simply be a non-issue for those users. Although who knows - maybe > that ends up being a real issue on Android.. A lot to digest, so I need to do some reading now. Thanks everyone! > > Linus