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charset=us-ascii Content-Disposition: inline In-Reply-To: <87ldctmosh.fsf@vajain21.in.ibm.com> X-TM-AS-GCONF: 00 X-Proofpoint-Reinject: loops=2 maxloops=12 X-Authority-Analysis: v=2.4 cv=HppG3UTS c=1 sm=1 tr=0 ts=6a26804d cx=c_pps a=3Bg1Hr4SwmMryq2xdFQyZA==:117 a=3Bg1Hr4SwmMryq2xdFQyZA==:17 a=kj9zAlcOel0A:10 a=FelO9ux0wxsA:10 a=VkNPw1HP01LnGYTKEx00:22 a=RnoormkPH1_aCDwRdu11:22 a=uAbxVGIbfxUO_5tXvNgY:22 a=VnNF1IyMAAAA:8 a=e3Y8OUfPrnf12rFgJ6AA:9 a=CjuIK1q_8ugA:10 X-Proofpoint-GUID: 1cOFj7y23auh6U6zkI4yS1SfysaPNzKj X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwNjA4MDA3OSBTYWx0ZWRfX8paRBT870B29 JYikC9zZA2cYMzuICjHLPc1xPtCyVVFx2LXxAyzBkkqIoWv7hU2HP7ebYWGZs3YIqBCOXonkoL7 KddPnCkctMPdHPf0lP5Ra7C7OD2bs05iHCjSB+o/tppHUjk0h82ytit4zIbYzz0KE1FKvMVwnpu 22uAA3F2t7H20hOxFWuGnySOVVovyA5bzcuVjEanTCr9LwOtfxiBy+yCj2A63RQp1Gt4A7Zw9Y3 5c5ymlgxsW8dxnH1otYTInGSDKeL383Gqe7eUDB8L15706QOwblq+F3J40b0MXoeoQqUz1IyUiu AWs0UnOHLqPj4rYid8MQYVOypnbWg1YfOAMYqk9HderLgVVlxXCUkvPr7jB0eRIC0o3Z1WpHWgF /0oD9S1uiIkP/WPgDJZ9tkalALs1/zv2/E+w+cakuTkwGcOZa/AxF6m6eAve4YD4WymEtGS/VI2 cGW4Q5L/iMCFXSdCPsA== X-Proofpoint-ORIG-GUID: ZtD31xyr9EAiG7G5dM9V5q-tjCIg3eF7 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1143,Hydra:6.1.125,FMLib:17.12.100.49 definitions=2026-06-08_02,2026-06-05_02,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 lowpriorityscore=0 adultscore=0 phishscore=0 malwarescore=0 impostorscore=0 priorityscore=1501 clxscore=1015 bulkscore=0 spamscore=0 suspectscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2605210000 definitions=main-2606080079 On Fri, Jun 05, 2026 at 12:55:50PM +0530, Vaibhav Jain wrote: > Hi Gautam, > > Thanks for testing this patch. Few questions: > Gautam Menghani writes: > > > On Wed, Jun 03, 2026 at 07:45:39PM +0530, Amit Machhiwal wrote: > >> On IBM POWER systems, newer processor generations can operate in > >> compatibility modes corresponding to earlier generations. This becomes > >> relevant for nested virtualization, where nested KVM guests may need to > >> run with a specific processor compatibility level. > >> > > > > > I booted a KVM guest on LPAR with this patch in the following scenarios: > > > > 3. P11 guest on P11 host booted in P10 compat mode: No error observed > This should have resulted in an error since booting a P11 guest on P10 > compat mode host is not allowed with/without this patch. Can you please > check your test env and share the boot results. - lscpu output (host P11 LPAR booted in p10 compat mode) # lscpu 03:35:13 [3/3] Architecture: ppc64le Byte Order: Little Endian CPU(s): 960 On-line CPU(s) list: 0-959 Model name: POWER10 (architected), altivec supported Model: 2.0 (pvr 0082 0200) Thread(s) per core: 8 Core(s) per socket: 15 Socket(s): 8 Physical sockets: 4 Physical chips: 2 Physical cores/chip: 16 - lscpu output from guest # lscpu Architecture: ppc64le Byte Order: Little Endian CPU(s): 4 On-line CPU(s) list: 0-3 Model name: Power11 (raw), altivec supported Model: 2.0 (pvr 0082 0200) Thread(s) per core: 1 Core(s) per socket: 4 Socket(s): 1 - QEMU command line /usr/bin/qemu-system-ppc64 -device virtio-blk-pci,drive=drive0,id=virtblk0 \ -drive file=/home/gautam/images/fc41.qcow2,format=qcow2,if=none,id=drive0 \ -m 100G -smp 4 -cpu host -nographic -machine pseries,ic-mode=xics -accel kvm Thanks, Gautam