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charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-TM-AS-GCONF: 00 X-Proofpoint-Reinject: loops=2 maxloops=12 X-Authority-Analysis: v=2.4 cv=PPc/P/qC c=1 sm=1 tr=0 ts=6a9a8e4d cx=c_pps a=GFwsV6G8L6GxiO2Y/PsHdQ==:117 a=GFwsV6G8L6GxiO2Y/PsHdQ==:17 a=IkcTkHD0fZMA:10 a=VdqzKS8jKosA:10 a=VkNPw1HP01LnGYTKEx00:22 a=RnoormkPH1_aCDwRdu11:22 a=iQ6ETzBq9ecOQQE5vZCe:22 a=NEAV23lmAAAA:8 a=VnNF1IyMAAAA:8 a=6rdme_d54tlq89W0LHkA:9 a=3ZKOabzyN94A:10 a=QEXdDO2ut3YA:10 X-Proofpoint-GUID: Hvn2tiHy5OOHoKa3sP7n_-RXMadeEURJ X-Proofpoint-ORIG-GUID: ROaXn4PGrGh4sxs_V4A7yuU0le0XwE8a X-Proofpoint-Spam-Info: AW1haW4tMjYwOTA0MDA4MiBTYWx0ZWRfX6QdJevZO3s3h 3hDRtTL5TLV7j6zuBXs5/Phcl327gep51naDB2dwOcz7uhXaLxEQ3NA+n9rAb6/1T59YL0mqTR0 rTIRvt4iPncwBL9tzFcok4r/Zq3LhJc= X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwOTA0MDA4MiBTYWx0ZWRfX5i4BKO5MlsT+ rsE6HXsSkBSOzO386GKktclNfXFIiExPnrvegXXMD1VUWEw8+woXjl4D7Sdpkn4jdHGK+UAxOC/ 0/NGZDr1X6vgD4iXLoOgRVEimQ/XWkXuMmF9URxMMxv2HEdUWXi92hHr+BfboZBH+SIyKZKxy8T PicZT1ArigCzonjzCvQyVqtRXVGhTzpAsKkvF2OaPVJsn5xYzIgBfItmKJgDubHMeSErVQ230AB c2wcKe+BmwMGHHaIa/aV+2q2SBOHJOrNfKNKN/czEglBknGfC0mv+p3ZxDde1pnM6pWG+tzabgB 5X7WuEpmu7UINYxHArgZoQMmlcZFdQYcFYUZHrxuHVyLXqopnKEOqSzCe6sFX8kyIsQJEpymzv6 WlLSlrrCpFSl266LX3xqZAoezSxfOsYL6LsY+RBua6SFqiFZAbsv2X7KtHqp6R8feUOMlilr2DU H7v6vLXkCj/XKheTMkQ== X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1176,Hydra:6.1.134,FMLib:17.12.100.49 definitions=2026-09-04_02,2026-09-03_01,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 clxscore=1015 phishscore=0 adultscore=0 suspectscore=0 bulkscore=0 spamscore=0 priorityscore=1501 impostorscore=0 malwarescore=0 lowpriorityscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2606150000 definitions=main-2609040082 On 9/4/26 2:50 PM, Christian Zigotzky wrote: > >> On 04 September 2026 at 10:56 Christian Zigotzky wrote: >> >> On 03 September 2026 at 07:23 Shrikanth Hegde wrote: >> >> Friendly LLM analysis says preemption is enabled too early and before >> completing kvmppc_handle_exit_hv() / kvmppc_handle_nested_exit() >> >> Below is ONLY a speculation and completely UNTESTED. >> Maybe worth a try. >> >> --- >> diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c >> index 0409ac9e7b31..78d2b0618887 100644 >> --- a/arch/powerpc/kvm/book3s_hv.c >> +++ b/arch/powerpc/kvm/book3s_hv.c >> @@ -5049,8 +5049,6 @@ int kvmhv_run_single_vcpu(struct kvm_vcpu *vcpu, u64 time_limit, >> >> powerpc_local_irq_pmu_restore(flags); >> >> - preempt_enable(); >> - >> /* >> * cancel pending decrementer exception if DEC is now positive, or if >> * entering a nested guest in which case the decrementer is now owned >> @@ -5072,6 +5070,8 @@ int kvmhv_run_single_vcpu(struct kvm_vcpu *vcpu, u64 time_limit, >> } >> vcpu->arch.ret = r; >> >> + preempt_enable(); >> + >> if (is_kvmppc_resume_guest(r) && !kvmppc_vcpu_check_block(vcpu)) { >> kvmppc_set_timer(vcpu); >> >> >> Michal >> >> - - - >> >> Michal, > > Sorry, I meant Shrikanth. > Leave that patch, it was only a speculation. >> >> Is this patch also for the issues with KVM PR and KVM HV if PREEMPT is activated? >> >> The entire FSL Cyrus+ board freezes when using KVM HV with PREEMPT. >> You have any logs? can you try with latest code? maybe 7.2? there is usage of generic api to handle the work now which renders the patch shared long back which you tried irrelevant. >> The guest kernel doesn't boot if we use KVM PR with a PREEMPT kernel on >> the PA Semi Nemo board. >> >> Bug report: https://github.com/chzigotzky/kernels/issues/19 >> >> Thanks, >> Christian >