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Zijlstra , Juri Lelli Cc: regressions@lists.linux.dev, stable@vger.kernel.org, linux-rt-users@vger.kernel.org, Lukas Beckmann Date: Mon, 11 May 2026 17:30:01 +0200 In-Reply-To: <20260511141441.stable-reply-0001@kernel.org> References: <04657838-46d1-432d-95e1-eb73b930b032@mailbox.org> <20260511141441.stable-reply-0001@kernel.org> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.56.2 Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Provags-ID: V03:K1:Dbvbhv0H6J1TilgRn0sneQjMh2C6vcPhUH1VmKWRqByOX3Pp9Pa 3ScMlm3zV8g9VxeQVJSFezhoVMuwhh6JhvX19/eJBxZqB9hJdEyd8ps9wImTWjwxNZDSgMp 6YKSDQKo4Q2qh/foY88trvj+ipIcuf5T6wpatC/36gzu/gSZbu9grzVnjK4L/vFy9xvjHTn 2hhuqtv2N6g9bu0zuyunA== X-Spam-Flag: NO UI-OutboundReport: notjunk:1;M01:P0:foBmjayto0E=;vZvKxesVJJU/R0973hArEWqdhZ/ 2ulP5ESu671bUx2z0fQmd0uztKPx7px+ZL5nw8FjeM5fN1UbAz0NIYugt9pqqYwl4CbtExjTu 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reproduces quickly: >=20 > =C2=A0 cccb45d7c429 ("sched/deadline: Less agressive dl_server handling") > =C2=A0 4ae8d9aa9f9d ("sched/deadline: Fix dl_server getting stuck") > =C2=A0 a3a70caf7906 ("sched/deadline: Fix dl_server behaviour") >=20 > d66792919d4f's upstream commit message explicitly says it relies on the > state established by a3a70caf7906, and none of the three are in 6.12.y. >=20 > Could you give those three commits a spin on top of 6.12.y (keeping > d66792919d4f in place) and see whether the latency goes away? I've meanwhile tried those three alone, and the size XXL hits my box readily reproduces in virgin source do indeed go away. 'course there may be another shoe, so... -Mike