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Fri, 30 Jan 2026 18:50:13 +0000 (GMT) Message-ID: Date: Sat, 31 Jan 2026 00:20:12 +0530 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [patch 2/4] sched/mmcid: Protect transition on weakly ordered systems To: Thomas Gleixner , LKML Cc: Ihor Solodrai , Peter Zijlstra , Mathieu Desnoyers , Michael Jeanson References: <20260129210219.452851594@kernel.org> <20260129211557.746946556@kernel.org> Content-Language: en-US From: Shrikanth Hegde In-Reply-To: <20260129211557.746946556@kernel.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 X-Proofpoint-GUID: u-E9kv5018PXaqVFTx4noGiNWo0rkFI8 X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwMTMwMDE1NCBTYWx0ZWRfX5NudgRTB6y0S 2UibfZMW9JE/54py1f9FqE6kHtDmNBKpXxs/iQWjjBRHPY4INB+YsKAZMaaAXDKjum/woHOAX0t hJ3AyqH0nwHP3YyfTuR15l81aKXPIwRMt5i5d8LaJxvgBcO4bsHA2J9P24AkAOlPiE4GjUgkCxF lpUz/jwmTfPlggt60GjP/Dnh0FusDPfS0sGdyrBONaVW4I6l9TiMKAthWZzzKeqNeiMy21O5VwP F24LcxVHDEg6b/9TD0aIXZEE9zM35G3o6w8ozGpJC9JRaaGh8WRkFemysNUDdynqAkdDZEqkcZr QI60uQLuFVukzBdgkV6lWcffmaOL8/aDmSzNvgRhBr06A3Y+g/MiMljsLUYnYdksCdFFRk9fkhC IYWSliNCxJnGi1pgQvgjxLcAYsx6Uw7pYAWB4cg0jrK8p4EcRJMkyhmuB9SX4jYnryocQPWx6Nq a51gvKVElSEhq/f78Zw== X-Authority-Analysis: v=2.4 cv=Zs3g6t7G c=1 sm=1 tr=0 ts=697cfd6b cx=c_pps a=GFwsV6G8L6GxiO2Y/PsHdQ==:117 a=GFwsV6G8L6GxiO2Y/PsHdQ==:17 a=IkcTkHD0fZMA:10 a=vUbySO9Y5rIA:10 a=VkNPw1HP01LnGYTKEx00:22 a=3v7e-wCndRFE-0Wu5LEA:9 a=QEXdDO2ut3YA:10 X-Proofpoint-ORIG-GUID: u-E9kv5018PXaqVFTx4noGiNWo0rkFI8 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1121,Hydra:6.1.51,FMLib:17.12.100.49 definitions=2026-01-30_02,2026-01-30_04,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 clxscore=1015 lowpriorityscore=0 adultscore=0 phishscore=0 suspectscore=0 bulkscore=0 impostorscore=0 priorityscore=1501 malwarescore=0 spamscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.19.0-2601150000 definitions=main-2601300154 Hi Thomas. On 1/30/26 2:50 AM, Thomas Gleixner wrote: > Shrikanth reported a hard lockup which he observed once. The stack trace > shows the following CID related participants: > I lost the system where this was seen once. But I gave the series a try on another power(NV) system. Ran schbench (which seems to execute some cid stuff) and hackbench and didn't see any splat in limited testing.