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Sat, 31 Jan 2026 06:10:31 +0000 (GMT) Message-ID: Date: Sat, 31 Jan 2026 11:40:30 +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: Mathieu Desnoyers Cc: Thomas Gleixner , Ihor Solodrai , Peter Zijlstra , Michael Jeanson , LKML References: <20260129210219.452851594@kernel.org> <20260129211557.746946556@kernel.org> Content-Language: en-US From: Shrikanth Hegde In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 X-Authority-Analysis: v=2.4 cv=UdxciaSN c=1 sm=1 tr=0 ts=697d9cdc cx=c_pps a=AfN7/Ok6k8XGzOShvHwTGQ==:117 a=AfN7/Ok6k8XGzOShvHwTGQ==:17 a=IkcTkHD0fZMA:10 a=vUbySO9Y5rIA:10 a=VkNPw1HP01LnGYTKEx00:22 a=IKHJyVW11ZIAJfYOPF8A:9 a=QEXdDO2ut3YA:10 X-Proofpoint-GUID: qgbglbFvLFC3SnWB4_zKlc7xgJ3fiUa0 X-Proofpoint-ORIG-GUID: qgbglbFvLFC3SnWB4_zKlc7xgJ3fiUa0 X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwMTMxMDA0NyBTYWx0ZWRfX2lCjAc9Af0uU CLSfbx2Fhi5zdAKXJvEUOy98txOORcILOBUyyXKwdtMv15StchnbEHR3Sxq+spftm8wnjCmH4UZ IpZUD4HyDZzCk5PWapKMBAZnCFMeTq9+KEOCXizANPrf/oS5YD6H2tU1/4IWvRroOVbVpbKli4N 2tin2rTgVSFtNbGGbke7QdGBRfPETdqsWM6eSktrqhx0lgRzg3lCcHYeVZi26nRRnIp5fOmJ64B jNbNi48THGhbNvIHVOTIrI2f4zaRaZ8dSEDJD4gdsAbCCuirdn5/dvTJ01hxE1LMjKIvL5IDQFH odyRwCpTQh5C1tn0HaTRBEXa3jpmqUR4R1U8vUefTrsCitnsG3SPjc2fKYZ6zQxzJ2ggiaDDjuZ DXsb0jyZV63OQe1mdkxSMcyCWpYSHF/aONfJhWOBzZX71NgmFCdjjWVs00Q+5ntwZIRTtYyim3c lscPTuz5H4jG6qI4pMA== 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_04,2026-01-30_04,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 impostorscore=0 lowpriorityscore=0 suspectscore=0 clxscore=1015 bulkscore=0 spamscore=0 phishscore=0 adultscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.19.0-2601150000 definitions=main-2601310047 Hi Mathieu. On 1/31/26 12:28 AM, Mathieu Desnoyers wrote: > On 2026-01-30 13:50, Shrikanth Hegde wrote: >> 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. > > Just out of curiosity, did you manage to reproduce the > splat on the new system without the fixes applied ? > > Thanks, > > Mathieu > No. I ran without the fixes. I didn't observe any splats either on this system.