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Tue, 23 Jan 2024 15:45:43 -0800 (PST) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 References: <20240122155023.GA26169@redhat.com> In-Reply-To: <20240122155023.GA26169@redhat.com> From: Dylan Hatch Date: Tue, 23 Jan 2024 15:45:31 -0800 Message-ID: Subject: Re: [PATCH v2 0/2] getrusage: use sig->stats_lock To: Oleg Nesterov Cc: Andrew Morton , "Eric W. Biederman" , linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Mon, Jan 22, 2024 at 7:51=E2=80=AFAM Oleg Nesterov wro= te: > > Dylan, do you have something to add? > > Oleg. > I have one last question -- is there possibly an edge case in which the hard lockup can still happen? How likely is it for many writers to force enough readers to do a retry on the seqlock, disabling irq and causing the lockup? Is this not a concern because there aren't many writers? Thanks, Dylan