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To: Samir M , "Paul E . McKenney" , Tejun Heo Cc: Boqun Feng , LKML , RCU , linuxppc-dev@lists.ozlabs.org, Boqun Feng References: <97a7d011-d573-4754-9e5d-68b562c64089@linux.ibm.com> <688280dc-78a2-4796-9eaf-e1c058836012@linux.ibm.com> <1b89c25b-7c1d-4ed8-adf3-ac504b6f086a@linux.ibm.com> Content-Language: en-US From: Shrikanth Hegde In-Reply-To: <1b89c25b-7c1d-4ed8-adf3-ac504b6f086a@linux.ibm.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 X-Proofpoint-Reinject: loops=2 maxloops=12 X-Authority-Analysis: v=2.4 cv=CIIamxrD c=1 sm=1 tr=0 ts=69f2451e cx=c_pps a=aDMHemPKRhS1OARIsFnwRA==:117 a=aDMHemPKRhS1OARIsFnwRA==:17 a=IkcTkHD0fZMA:10 a=A5OVakUREuEA:10 a=VkNPw1HP01LnGYTKEx00:22 a=RnoormkPH1_aCDwRdu11:22 a=RzCfie-kr_QcCd8fBx8p:22 a=VwQbUJbxAAAA:8 a=qCof3rqyAAAA:8 a=SltLtrhv4OmeOPo6kIgA:9 a=QEXdDO2ut3YA:10 a=zZCYzV9kfG8A:10 a=sGiMcuukUhmiu4iKGgn_:22 X-Proofpoint-ORIG-GUID: _sOAm_Wn_KlF51Dlhb5XpF1pXgwTbLan X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwNDI5MDE3OSBTYWx0ZWRfX2zilRbQWtkR8 v3KGwBmpl5pBm77d04qsz0DkmjiKJ0Up26LcB/jhjsWr1t0KxA/bXM/X3zBkprgivvo8jAZnhUZ P704EBAIZn379VChyaZpLPCKe4d1KBdpXkCiuEd5knjdpZr+wSF9ewlCs+BhP/TDakDgaaPvpm/ vnAaPhkIgr4Bb6o/HuV2dENP/R45hNtCAVOmJQr7k8cBoKeIkazk65LobbTU6R6ozPc5MjLmcKs Z1GxBEWMLSaO3D7Z9+obgwRaJvu1qrErLFFZ2PWy4EcasKfHEwiD6gNMEuY4OdGxiDURSpdf1VL xpu6x5QVAT0M0+VxWaHNS+Q8I9CU3oKyOjYBB6VQuWVU/ZSgGG8hEUq8Z3XKDmm3jC+FcnFrfyI s4p+4ARb95f3bRW/5H+J3YqMZvsDp80C0GJYtZQRafYVd9rJA37OMoT7+ZzJwE3fbhH210ZLWU4 r9Xf6/7EZGcVtuT1HdA== X-Proofpoint-GUID: vXQyVNRMRfTYp_w2LZbMfCxWk6vLQHUy X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1143,Hydra:6.1.51,FMLib:17.12.100.49 definitions=2026-04-29_01,2026-04-28_01,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 phishscore=0 malwarescore=0 suspectscore=0 adultscore=0 impostorscore=0 lowpriorityscore=0 clxscore=1015 bulkscore=0 priorityscore=1501 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2604200000 definitions=main-2604290179 Hi Samir. On 4/29/26 3:46 PM, Samir M wrote: > > Hi Boqun, > > Thank you for pointing me to the existing patches. I have tested both > Paul's patch [1] and TJ's workqueue patch [2] on my PowerPC system (80 > CPUs), and can confirm that the workqueue lockup issue is not observed. > Can you try only paul's patch and confirm if the issue is fixed? > Test Environment: > - System: PowerPC with 80 CPUs ( e.g. PowerPC LPARs with 80 online and > 384 possible CPUs) > - Kernel version: Latest upstream (7.1-rc1) > > Regression Testing Results: > All tests completed successfully with no issues observed: > - Hackbench > - Kernel selftests > - LTP scheduler tests > > The workqueue lockup that was previously occurring is no longer present > with the patches applied. > > References: > [1]: https://lore.kernel.org/rcu/ed1fa6cd-7343-4ca3-8b9d- > d699ca496f83@paulmck-laptop/ > [2]: https://lore.kernel.org/rcu/adlHKowvhn8AGXCc@slm.duckdns.org/ > > Best regards, > Samir