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Mon, 07 Sep 2026 10:07:09 -0700 (PDT) Date: Mon, 7 Sep 2026 19:07:07 +0200 From: Michal =?utf-8?Q?Koutn=C3=BD?= To: Tejun Heo , cgroups@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Dan Schatzberg , Peter Zijlstra , stable@vger.kernel.org, Noah Elias Feldt , Salvatore Bonaccorso , Johannes Weiner Subject: Re: [PATCH v2] cgroup: Avoid iteration of dying tasks with zero refcount Message-ID: References: <20260907170345.45316-1-mkoutny@suse.com> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="jtnc6cwmahlcj6p2" Content-Disposition: inline In-Reply-To: <20260907170345.45316-1-mkoutny@suse.com> --jtnc6cwmahlcj6p2 Content-Type: text/plain; protected-headers=v1; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Subject: Re: [PATCH v2] cgroup: Avoid iteration of dying tasks with zero refcount MIME-Version: 1.0 On Mon, Sep 07, 2026 at 07:03:44PM +0200, Michal Koutn=FD wrote: > cgroup_task_release() is not synced via css_set_lock hence the race > possibility. (I'm not 100% convinced about this LLM-assisted > interleaving, multiple css_task_iter_next() calls may be involved with > css_set_lock released.) This paragraph should be editted out too because of > Changes from v1 (https://lore.kernel.org/r/20260902161653.1051794-1-mkout= ny@suse.com) > - add css_set_lock release to sequence diagram (Sorry for multi-messaging.) Michal --jtnc6cwmahlcj6p2 Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iJEEABYKADkWIQRCE24Fn/AcRjnLivR+PQLnlNv4CAUCap7vNxsUgAAAAAAEAA5t YW51MiwyLjUrMS4xMiwyLDIACgkQfj0C55Tb+AhioQEAmJhHHhGjIo7Om5IAREUA o0BeFqPGwj+N8w9xPavgGs0BAJ2+iIXGFwdVXInVdS+Qs/Dz2jNb/b3impZkCl5P p/MF =DHgd -----END PGP SIGNATURE----- --jtnc6cwmahlcj6p2--