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charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: X-TM-AS-GCONF: 00 X-Proofpoint-Reinject: loops=2 maxloops=12 X-Proofpoint-ORIG-GUID: 5F5gkDbRgvwGpH78-BU-Iok2j7buPhUe X-Proofpoint-GUID: f31wF4AfIMydrYbqZTCjlIiOdJMLigr5 X-Authority-Analysis: v=2.4 cv=XqfK/1F9 c=1 sm=1 tr=0 ts=6a186810 cx=c_pps a=aDMHemPKRhS1OARIsFnwRA==:117 a=aDMHemPKRhS1OARIsFnwRA==:17 a=8nJEP1OIZ-IA:10 a=NGcC8JguVDcA:10 a=VkNPw1HP01LnGYTKEx00:22 a=RnoormkPH1_aCDwRdu11:22 a=Y2IxJ9c9Rs8Kov3niI8_:22 a=pGLkceISAAAA:8 a=VnNF1IyMAAAA:8 a=iuu2KmbQcLBheBbGiaYA:9 a=3ZKOabzyN94A:10 a=wPNLvfGTeEIA:10 X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwNTI4MDE2MyBTYWx0ZWRfXwChZDdV2nNUM gk5hg0WSOVA+mVE/ZFaHEPWox8F7Hq/NlxsbEdpkZ9+sfzZL7i+qdZ6MCGfAyEhTUk4ec4yRN7J kJNzwheW2HaXPFeeqXczQsIPdhx7uwb52/ili/AcfF5lV87RtvFkshOAmkpeaxjN5DOelHiErof olsT/dB0dbVpjFcIrM7axNF1BdiT5NNO6TOTO7obIb6yRzzHZHww9hQOpiz28esKRwgSWRw+AsE d6mHSDTWMjkd5xdB9XAr3RG5r4lQalxL6MOjeCSaUGgwakgDNTG5D4nMVkcc+qQc5BSLpY/aLVN P4eZn95cjsUcLuWnoZC2HaY4mBpuZq9Fb7BfOhXsTckTlseappK1dAe+/Acknr99uT7qJZDduVz CBnlO8YuTD9rkkHDPo36vyL38UtmqTVEvvJQ/y9k/CeQ0H23C3ZIWggijc6Uavw1/5f4zTBlQ0r 2ItVfTI4rtvy44dDcjQ== 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=2026-05-28_04,2026-05-28_03,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 malwarescore=0 spamscore=0 impostorscore=0 adultscore=0 phishscore=0 priorityscore=1501 lowpriorityscore=0 bulkscore=0 suspectscore=0 clxscore=1015 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2605210000 definitions=main-2605280163 * Ritesh Harjani [2026-05-28 12:24:39]: > Venkat Rao Bagalkote writes: > > > Greetings!!! > > > > I am seeing an early boot kernel panic due to NULL pointer dereference > > on a POWER9 (pSeries) system when testing linux-next (next-20260522). > > > > > > [    0.039029] NIP [c000000000e58504] _find_first_bit+0x44/0x130 > > [    0.039043] LR [c000000000e58500] _find_first_bit+0x40/0x130 > > [    0.039054] Call Trace: > > [    0.039060] [c0000000090e7b80] [c00000000416af20] > > schedutil_gov+0x0/0xa0 (unreliable) > > [    0.039076] [c0000000090e7bc0] [c00000000038b3b8] > > build_sched_domains+0xad8/0xe50 > > [    0.039089] [c0000000090e7ce0] [c000000003045d78] > > sched_init_smp+0xa8/0x164 > > [    0.039102] [c0000000090e7d30] [c00000000300f374] > > kernel_init_freeable+0x250/0x370 > > [    0.039117] [c0000000090e7de0] [c000000000011f90] kernel_init+0x34/0x1e4 > > [    0.039129] [c0000000090e7e50] [c00000000000debc] > > ret_from_kernel_user_thread+0x14/0x1c > > [    0.039142] ---- interrupt: 0 at 0x0 > > [    0.039150] Code: 41820090 7c0802a6 393cffff fbe10038 7c7f1b78 > > fba10028 fbc10030 3bc00000 793dd7e2 f8010050 4bae6e9d 60000000 > > 2c290000 408200bc 283c0040 > > [    0.039196] ---[ end trace 0000000000000000 ]--- > > > > > > Well, I am hitting this on 7.1.0-rc5-next-20260526-00010-gbfac43765a97 > with Qemu Pseries TCG power10/11. > Qemu Pseries guest would be a shared lpar. So thats expected to be similar to P9. We would not have a coregroup_map allocated. > [ 0.342868][ T1] smp: Bringing up secondary CPUs ... > [ 0.342868][ T1] smp: Bringing up secondary CPUs ... > [ 0.525419][ T1] smp: Brought up 1 node, 4 CPUs > [ 0.525419][ T1] smp: Brought up 1 node, 4 CPUs > [ 0.527992][ T1] numa: Node 0 CPUs: 0-3 > [ 0.527992][ T1] numa: Node 0 CPUs: 0-3 > [ 0.552787][ T1] BUG: Kernel NULL pointer dereference on read at 0x00000000 > [ 0.552787][ T1] BUG: Kernel NULL pointer dereference on read at 0x00000000 > [ 0.557446][ T1] Faulting instruction address: 0xc000000000fe3f1c > [ 0.557446][ T1] Faulting instruction address: 0xc000000000fe3f1c > cpu 0x0: Vector: 300 (Data Access) at [c000000006607800] > pc: c000000000fe3f1c: _find_first_bit+0xc/0xc0 > lr: c00000000027b7d8: build_sched_domains+0xbb4/0x1938 > sp: c000000006607ac0 > msr: 8000000002009033 > dar: 0 > dsisr: 80000 > current = 0xc000000006f9fb00 > paca = 0xc000000005670000 irqmask: 0x03 irq_happened: 0x09 > pid = 1, comm = swapper/0 > Linux version 7.1.0-rc5-next-20260526-00010-gbfac43765a97-dirty (powerpc64le-linux-gnu-gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40) #19 SMP PREEMPT Thu May 28 12:29:51 IST 2026 > enter ? for help > [link register ] c00000000027b7d8 build_sched_domains+0xbb4/0x1938 > [c000000006607ac0] c00000000027b0a8 build_sched_domains+0x484/0x1938 (unreliable) > [c000000006607c20] c000000004053180 sched_init_domains+0x114/0x1cc > [c000000006607c70] c0000000040515e0 sched_init_smp+0x5c/0x17c > [c000000006607cc0] c000000004012888 kernel_init_freeable+0x258/0x790 > [c000000006607dc0] c000000000011f3c kernel_init+0x34/0x268 > [c000000006607e30] c00000000000debc ret_from_kernel_user_thread+0x14/0x1c > ---- Exception: 0 at 0000000000000000 > > > > -ritesh -- Thanks and Regards Srikar Dronamraju