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McKenney" , "Gautham R. Shenoy" , Tim Chen , Yury Norov , Shrikanth Hegde Subject: Re: [patch V3 20/20] sched/mmcid: Switch over to the new mechanism In-Reply-To: <6956f6c1-ad8a-4024-ac85-33ab6529b3de@sirena.org.uk> (Mark Brown's message of "Mon, 24 Nov 2025 12:10:17 +0000") References: <20251029123717.886619142@linutronix.de> <20251029124516.529828589@linutronix.de> <6956f6c1-ad8a-4024-ac85-33ab6529b3de@sirena.org.uk> Date: Mon, 24 Nov 2025 13:27:15 +0100 Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain X-Scanned-By: MIMEDefang 3.0 on 10.30.177.17 * Mark Brown: > On Wed, Oct 29, 2025 at 02:09:32PM +0100, Thomas Gleixner wrote: >> Now that all pieces are in place, change the implementations of >> sched_mm_cid_fork() and sched_mm_cid_exit() to adhere to the new strict >> ownership scheme and switch context_switch() over to use the new >> mm_cid_schedin() functionality. >> >> The common case is that there is no mode change required, which makes >> fork() and exit() just update the user count and the constraints. > > I'm seeing boot failures on x86 qemu in -next which bisect to this > patch. The boot gets to userspace but then grinds to a halt: > > https://lava.sirena.org.uk/scheduler/job/2118455#L542 > > which isn't terribly informative unfortunately. I don't have any x86 > hardware, and nothing else seems affected. I believe that's already discussed here: Thanks, Florian