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smtpav02.fra02v.mail.ibm.com (Postfix) with ESMTP; Wed, 11 Oct 2023 10:53:26 +0000 (GMT) Message-ID: <4bb6a4a0-525b-d36d-c5ac-127357e96eb3@linux.ibm.com> Date: Wed, 11 Oct 2023 16:23:25 +0530 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.15.1 Subject: Re: [PATCHv8 1/5] powerpc/setup : Enable boot_cpu_hwid for PPC32 Content-Language: en-US To: Pingfan Liu , linuxppc-dev@lists.ozlabs.org References: <20231009113036.45988-1-piliu@redhat.com> <20231009113036.45988-2-piliu@redhat.com> <36b2aa11-dfd9-529d-0386-aa181caeb93f@linux.ibm.com> <7da645c3-2899-fb01-bf11-392b9bd52e38@linux.ibm.com> From: Sourabh Jain In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-TM-AS-GCONF: 00 X-Proofpoint-GUID: B0mh-h6G1tEfokoWgjrW-oiDiXNIKU9z X-Proofpoint-ORIG-GUID: meEowEEfSJCJg8QWZkXjIMn2jNyQv6aA X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.267,Aquarius:18.0.980,Hydra:6.0.619,FMLib:17.11.176.26 definitions=2023-10-11_08,2023-10-11_01,2023-05-22_02 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 mlxscore=0 suspectscore=0 mlxlogscore=999 phishscore=0 priorityscore=1501 bulkscore=0 spamscore=0 adultscore=0 malwarescore=0 impostorscore=0 clxscore=1015 lowpriorityscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2309180000 definitions=main-2310110095 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Baoquan He , kexec@lists.infradead.org, Mahesh Salgaonkar , Nicholas Piggin , Ming Lei , Wen Xiong Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" Hello Pingfan, >>> With this patch series applied, the kdump kernel fails to boot on >>> powerpc with nr_cpus=1. >>> >>> Console logs: >>> ------------------- >>> [root]# echo c > /proc/sysrq-trigger >>> [   74.783235] sysrq: Trigger a crash >>> [   74.783244] Kernel panic - not syncing: sysrq triggered crash >>> [   74.783252] CPU: 58 PID: 3838 Comm: bash Kdump: loaded Not tainted >>> 6.6.0-rc5pf-nr-cpus+ #3 >>> [   74.783259] Hardware name: POWER10 (raw) phyp pSeries >>> [   74.783275] Call Trace: >>> [   74.783280] [c00000020f4ebac0] [c000000000ed9f38] >>> dump_stack_lvl+0x6c/0x9c (unreliable) >>> [   74.783291] [c00000020f4ebaf0] [c000000000150300] panic+0x178/0x438 >>> [   74.783298] [c00000020f4ebb90] [c000000000936d48] >>> sysrq_handle_crash+0x28/0x30 >>> [   74.783304] [c00000020f4ebbf0] [c00000000093773c] >>> __handle_sysrq+0x10c/0x250 >>> [   74.783309] [c00000020f4ebc90] [c000000000937fa8] >>> write_sysrq_trigger+0xc8/0x168 >>> [   74.783314] [c00000020f4ebcd0] [c000000000665d8c] >>> proc_reg_write+0x10c/0x1b0 >>> [   74.783321] [c00000020f4ebd00] [c00000000058da54] >>> vfs_write+0x104/0x4b0 >>> [   74.783326] [c00000020f4ebdc0] [c00000000058dfdc] >>> ksys_write+0x7c/0x140 >>> [   74.783331] [c00000020f4ebe10] [c000000000033a64] >>> system_call_exception+0x144/0x3a0 >>> [   74.783337] [c00000020f4ebe50] [c00000000000c554] >>> system_call_common+0xf4/0x258 >>> [   74.783343] --- interrupt: c00 at 0x7fffa0721594 >>> [   74.783352] NIP:  00007fffa0721594 LR: 00007fffa0697bf4 CTR: >>> 0000000000000000 >>> [   74.783364] REGS: c00000020f4ebe80 TRAP: 0c00   Not tainted >>> (6.6.0-rc5pf-nr-cpus+) >>> [   74.783376] MSR:  800000000280f033 >>>   CR: 28222202  XER: 00000000 >>> [   74.783394] IRQMASK: 0 >>> [   74.783394] GPR00: 0000000000000004 00007ffffc4b6800 00007fffa0807300 >>> 0000000000000001 >>> [   74.783394] GPR04: 000000013549ea60 0000000000000002 0000000000000010 >>> 0000000000000000 >>> [   74.783394] GPR08: 0000000000000000 0000000000000000 0000000000000000 >>> 0000000000000000 >>> [   74.783394] GPR12: 0000000000000000 00007fffa0abaf70 0000000040000000 >>> 000000011a0f9798 >>> [   74.783394] GPR16: 000000011a0f9724 000000011a097688 000000011a02ff70 >>> 000000011a0fd568 >>> [   74.783394] GPR20: 0000000135554bf0 0000000000000001 000000011a0aa478 >>> 00007ffffc4b6a24 >>> [   74.783394] GPR24: 00007ffffc4b6a20 000000011a0faf94 0000000000000002 >>> 000000013549ea60 >>> [   74.783394] GPR28: 0000000000000002 00007fffa08017a0 000000013549ea60 >>> 0000000000000002 >>> [   74.783440] NIP [00007fffa0721594] 0x7fffa0721594 >>> [   74.783443] LR [00007fffa0697bf4] 0x7fffa0697bf4 >>> [   74.783447] --- interrupt: c00 >>> I'm in purgatory >>> [    0.000000] radix-mmu: Page sizes from device-tree: >>> [    0.000000] radix-mmu: Page size shift = 12 AP=0x0 >>> [    0.000000] radix-mmu: Page size shift = 16 AP=0x5 >>> [    0.000000] radix-mmu: Page size shift = 21 AP=0x1 >>> [    0.000000] radix-mmu: Page size shift = 30 AP=0x2 >>> [    0.000000] Activating Kernel Userspace Access Prevention >>> [    0.000000] Activating Kernel Userspace Execution Prevention >>> [    0.000000] radix-mmu: Mapped 0x0000000000000000-0x0000000000010000 >>> with 64.0 KiB pages (exec) >>> [    0.000000] radix-mmu: Mapped 0x0000000000010000-0x0000000000200000 >>> with 64.0 KiB pages >>> [    0.000000] radix-mmu: Mapped 0x0000000000200000-0x0000000020000000 >>> with 2.00 MiB pages >>> [    0.000000] radix-mmu: Mapped 0x0000000020000000-0x0000000022600000 >>> with 2.00 MiB pages (exec) >>> [    0.000000] radix-mmu: Mapped 0x0000000022600000-0x0000000040000000 >>> with 2.00 MiB pages >>> [    0.000000] radix-mmu: Mapped 0x0000000040000000-0x0000000180000000 >>> with 1.00 GiB pages >>> [    0.000000] radix-mmu: Mapped 0x0000000180000000-0x00000001a0000000 >>> with 2.00 MiB pages >>> [    0.000000] lpar: Using radix MMU under hypervisor >>> [    0.000000] Linux version 6.6.0-rc5pf-nr-cpus+ >>> (root@ltcever7x0-lp1.aus.stglabs.ibm.com) (gcc (GCC) 8.5.0 20210514 (Red >>> Hat 8.5.0-20), GNU ld version 2.30-123.el8) #3 SMP Mon Oct  9 11:07: >>> 41 CDT 2023 >>> [    0.000000] Found initrd at 0xc000000022e60000:0xc0000000248f08d8 >>> [    0.000000] Hardware name: IBM,9043-MRX POWER10 (raw) 0x800200 >>> 0xf000006 of:IBM,FW1060.00 (NM1060_016) hv:phyp pSeries >>> [    0.000000] printk: bootconsole [udbg0] enabled >>> [    0.000000] the round shift between dt seq and the cpu logic number: >>> 56 >>> [    0.000000] BUG: Unable to handle kernel data access on write at >>> 0xc0000001a0000000 >>> [    0.000000] Faulting instruction address: 0xc000000022009c64 >>> [    0.000000] Oops: Kernel access of bad area, sig: 11 [#1] >>> [    0.000000] LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=2048 NUMA pSeries >>> [    0.000000] Modules linked in: >>> [    0.000000] CPU: 2 PID: 0 Comm: swapper Not tainted >>> 6.6.0-rc5pf-nr-cpus+ #3 >>> [    0.000000] Hardware name:  POWER10 (raw)  hv:phyp pSeries >>> [    0.000000] NIP:  c000000022009c64 LR: c000000022009c54 CTR: >>> c0000000201ff348 >>> [    0.000000] REGS: c000000022aebb00 TRAP: 0300   Not tainted >>> (6.6.0-rc5pf-nr-cpus+) >>> [    0.000000] MSR:  8000000000001033 CR: 28222824 >>> XER: 00000001 >>> [    0.000000] CFAR: c000000020031574 DAR: c0000001a0000000 DSISR: >>> 42000000 IRQMASK: 1 >>> [    0.000000] GPR00: c000000022009ba0 c000000022aebda0 c0000000213d1300 >>> 0000000000000004 >>> [    0.000000] GPR04: 0000000000000001 c000000022aebbc0 c000000022aebbb8 >>> 0000000000000000 >>> [    0.000000] GPR08: 0000000000000001 c00000019ffffff8 000000000000003a >>> c0000000229c8a78 >>> [    0.000000] GPR12: 0000000000002000 c000000022e4a800 c0000000211d34b8 >>> c0000000211d3aa8 >>> [    0.000000] GPR16: c0000000211d75a0 c0000000211d75b0 c0000000225f3b98 >>> 0000000000000000 >>> [    0.000000] GPR20: 0000000000000001 0000000000000001 0000000000000001 >>> 0000000000000001 >>> [    0.000000] GPR24: 0000000000000008 0000000000000000 0000000000000001 >>> c00000019ffffdc0 >>> [    0.000000] GPR28: 0000000000000002 c000000022b368e0 c000000022aebe08 >>> 0000000000000008 >>> [    0.000000] NIP [c000000022009c64] smp_setup_cpu_maps+0x420/0x724 >>> [    0.000000] LR [c000000022009c54] smp_setup_cpu_maps+0x410/0x724 >>> [    0.000000] Call Trace: >>> [    0.000000] [c000000022aebda0] [c000000022009ba0] >>> smp_setup_cpu_maps+0x35c/0x724 (unreliable) >>> [    0.000000] [c000000022aebeb0] [c00000002200a19c] >>> setup_arch+0x1b8/0x54c >>> [    0.000000] [c000000022aebf30] [c000000022003f88] >>> start_kernel+0xb0/0x768 >>> [    0.000000] [c000000022aebfe0] [c00000002000d888] >>> start_here_common+0x1c/0x20 >>> [    0.000000] Code: 3929ffff 7f89e040 409c002c 7ec4b378 7f83e378 >>> 4a027939 7f83e378 4a0278e5 e95b0018 3d22017d e929f028 7d4ac42c >>> <7d49c12e> eb7b0000 7e99a378 4bffff3c >> The faulting instruction address, 0xc000000022009c6, corresponds to the code >> below: >> >> File: >> arch/powerpc/kernel/setup-common.c >> >> Function >> void __init smp_setup_cpu_maps(void) >> { >>             ... >>             cpu_to_phys_id[bt_thread] = >> be32_to_cpu(intserv_node->intserv[bt_thread]); >>             ... >> } >> >> Hope it helps. >> > Appreciate your help. > > This issue should be linked with the capability of cpu_to_phys_id[]. > > Could you please to try the fix suggested at the end of the email? > It should be a fix for > [PATCHv8 3/5] powerpc/setup: Handle the case when boot_cpuid greater than nr_cpus > > > Thanks, > > Pingfan > > --- > > diff --git a/arch/powerpc/kernel/setup-common.c b/arch/powerpc/kernel/setup-common.c > index bd7853a4bc91..849adc7a4b47 100644 > --- a/arch/powerpc/kernel/setup-common.c > +++ b/arch/powerpc/kernel/setup-common.c > @@ -464,12 +464,6 @@ void __init smp_setup_cpu_maps(void) > DBG("smp_setup_cpu_maps()\n"); > > INIT_LIST_HEAD(&head); > - cpu_to_phys_id = memblock_alloc(nr_cpu_ids * sizeof(u32), > - __alignof__(u32)); > - if (!cpu_to_phys_id) > - panic("%s: Failed to allocate %zu bytes align=0x%zx\n", > - __func__, nr_cpu_ids * sizeof(u32), __alignof__(u32)); > - > for_each_node_by_type(dn, "cpu") { > const __be32 *intserv; > __be32 cpu_be; > @@ -533,6 +527,16 @@ void __init smp_setup_cpu_maps(void) > } > > } > + > + /* There may be hole between cpu0 and boot cpu */ > + j = (bt_thread + 1) > nr_cpu_ids ? (bt_thread + 1) : nr_cpu_ids; > + cpu_to_phys_id = memblock_alloc(j * sizeof(u32), > + __alignof__(u32)); > + if (!cpu_to_phys_id) > + panic("%s: Failed to allocate %zu bytes align=0x%zx\n", > + __func__, nr_cpu_ids * sizeof(u32), __alignof__(u32)); > + > + > cpu = 0; > list_del_init(&head); > /* Select the primary thread, the boot cpu's slibing, as the logic 0 */ With the above changes applied, kdump kernel boots fine with a WARNING: [root]# echo c > /proc/sysrq-trigger [  310.748248] sysrq: Trigger a crash [  310.748256] Kernel panic - not syncing: sysrq triggered crash [  310.748266] CPU: 26 PID: 2610 Comm: bash Kdump: loaded Not tainted 6.6.0-rc5-fix-setup-common+ #3 [  310.748273] Hardware name: IBM,9043-MRX POWER10  hv:phyp pSeries [  310.748280] Call Trace: [  310.748284] [c000000184717ac0] [c000000000ecf8d8] dump_stack_lvl+0x6c/0x9c (unreliable) [  310.748298] [c000000184717af0] [c000000000150310] panic+0x178/0x438 [  310.748307] [c000000184717b90] [c00000000092c8b8] sysrq_handle_crash+0x28/0x30 [  310.748316] [c000000184717bf0] [c00000000092d2ac] __handle_sysrq+0x10c/0x250 [  310.748330] [c000000184717c90] [c00000000092db18] write_sysrq_trigger+0xc8/0x168 [  310.748339] [c000000184717cd0] [c00000000065c21c] proc_reg_write+0x10c/0x1b0 [  310.748349] [c000000184717d00] [c000000000583f94] vfs_write+0x104/0x4b0 [  310.748356] [c000000184717dc0] [c00000000058451c] ksys_write+0x7c/0x140 [  310.748365] [c000000184717e10] [c000000000033a54] system_call_exception+0x144/0x3a0 [  310.748377] [c000000184717e50] [c00000000000c554] system_call_common+0xf4/0x258 [  310.748389] --- interrupt: c00 at 0x7fff97720c34 [  310.748395] NIP:  00007fff97720c34 LR: 00007fff97697c74 CTR: 0000000000000000 [  310.748404] REGS: c000000184717e80 TRAP: 0c00   Not tainted (6.6.0-rc5-fix-setup-common+) [  310.748413] MSR:  800000000280f033   CR: 28222202  XER: 00000000 [  310.748430] IRQMASK: 0 [  310.748430] GPR00: 0000000000000004 00007fffffabc510 00007fff97807300 0000000000000001 [  310.748430] GPR04: 00000001624f7910 0000000000000002 0000000000000010 00007fff97669724 [  310.748430] GPR08: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 [  310.748430] GPR12: 0000000000000000 00007fff97a5aee0 0000000040000000 0000000125c39798 [  310.748430] GPR16: 0000000125c39724 0000000125bd8128 0000000125b70370 0000000125c3d568 [  310.748430] GPR20: 0000000162551030 0000000000000001 0000000125beaf18 00007fffffabc734 [  310.748430] GPR24: 00007fffffabc730 0000000125c3af94 0000000000000002 00000001624f7910 [  310.748430] GPR28: 0000000000000002 00007fff97801798 00000001624f7910 0000000000000002 [  310.748475] NIP [00007fff97720c34] 0x7fff97720c34 [  310.748478] LR [00007fff97697c74] 0x7fff97697c74 [  310.748482] --- interrupt: c00 I'm in purgatory [    0.000000] radix-mmu: Page sizes from device-tree: [    0.000000] radix-mmu: Page size shift = 12 AP=0x0 [    0.000000] radix-mmu: Page size shift = 16 AP=0x5 [    0.000000] radix-mmu: Page size shift = 21 AP=0x1 [    0.000000] radix-mmu: Page size shift = 30 AP=0x2 [    0.000000] Activating Kernel Userspace Access Prevention [    0.000000] Activating Kernel Userspace Execution Prevention [    0.000000] radix-mmu: Mapped 0x0000000000000000-0x0000000000010000 with 64.0 KiB pages (exec) [    0.000000] radix-mmu: Mapped 0x0000000000010000-0x0000000000200000 with 64.0 KiB pages [    0.000000] radix-mmu: Mapped 0x0000000000200000-0x0000000020000000 with 2.00 MiB pages [    0.000000] radix-mmu: Mapped 0x0000000020000000-0x0000000022600000 with 2.00 MiB pages (exec) [    0.000000] radix-mmu: Mapped 0x0000000022600000-0x0000000040000000 with 2.00 MiB pages Trimmed logs .... [    0.001738] Mount-cache hash table entries: 16384 (order: 1, 131072 bytes, linear) [    0.001751] Mountpoint-cache hash table entries: 16384 (order: 1, 131072 bytes, linear) [    0.007339] ------------[ cut here ]------------ [    0.007356] WARNING: CPU: 2 PID: 1 at arch/powerpc/kernel/smp.c:941 update_mask_from_threadgroup+0x128/0x1a0 [    0.007371] Modules linked in: [    0.007377] CPU: 2 PID: 1 Comm: swapper/2 Not tainted 6.6.0-rc5-fix-setup-common+ #3 [    0.007385] Hardware name: IBM,9043-MRX POWER10 hv:phyp pSeries [    0.007393] NIP:  c000000022011ed8 LR: c000000022011e10 CTR: 0000000000000000 [    0.007411] REGS: c0000000256338f0 TRAP: 0700   Not tainted (6.6.0-rc5-fix-setup-common+) [    0.007425] MSR:  8000000002029033   CR: 44000842  XER: 0000000c [    0.007444] CFAR: c000000022011e78 IRQMASK: 0 [    0.007444] GPR00: c000000022011e10 c000000025633b90 c0000000213c1300 0000000000000002 [    0.007444] GPR04: 0000000000000000 0000000000000005 0000000000000001 0000000000000002 [    0.007444] GPR08: 0000000000000008 0000000000000001 0000000000000002 0000000000000004 [    0.007444] GPR12: 0000000000000000 c000000022e3ac00 c000000020010138 0000000000000000 [    0.007444] GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 [    0.007444] GPR20: 0000000000000018 c000000022150968 c000000022093580 c0000000253df000 [    0.007444] GPR24: 0000000000000002 0000000000000000 c000000022b32058 0000000000000000 [    0.007444] GPR28: c00000015fca0a68 c000000022ba0330 c00000002209352c 0000000000000000 [    0.007520] NIP [c000000022011ed8] update_mask_from_threadgroup+0x128/0x1a0 [    0.007528] LR [c000000022011e10] update_mask_from_threadgroup+0x60/0x1a0 [    0.007536] Call Trace: [    0.007539] [c000000025633b90] [c000000022011e10] update_mask_from_threadgroup+0x60/0x1a0 (unreliable) [    0.007550] [c000000025633be0] [c000000022012210] init_thread_group_cache_map+0x2c0/0x338 [    0.007559] [c000000025633c50] [c0000000220125a0] smp_prepare_cpus+0x318/0x510 [    0.007568] [c000000025633d10] [c000000022004874] kernel_init_freeable+0x198/0x3cc [    0.007578] [c000000025633de0] [c000000020010164] kernel_init+0x34/0x1b0 [    0.007586] [c000000025633e50] [c00000002000cd94] ret_from_kernel_user_thread+0x14/0x1c [    0.007596] --- interrupt: 0 at 0x0 [    0.007601] NIP:  0000000000000000 LR: 0000000000000000 CTR: 0000000000000000 [    0.007608] REGS: c000000025633e80 TRAP: 0000   Not tainted (6.6.0-rc5-fix-setup-common+) [    0.007632] MSR:  0000000000000000 <>  CR: 00000000  XER: 00000000 [    0.007651] CFAR: 0000000000000000 IRQMASK: 0 [    0.007651] GPR00: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 [    0.007651] GPR04: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 [    0.007651] GPR08: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 [    0.007651] GPR12: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 [    0.007651] GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 [    0.007651] GPR20: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 [    0.007651] GPR24: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 [    0.007651] GPR28: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 [    0.007742] NIP [0000000000000000] 0x0 [    0.007756] LR [0000000000000000] 0x0 [    0.007769] --- interrupt: 0 [    0.007779] Code: 7ca507b4 79081764 7d1e4214 8108000c 7f882000 409effdc 48000010 38e70001 7ce707b4 4bffffa4 2f8affff 409e0010 <0fe00000> 3860ffc3 4800004c 7f9b5000 [    0.007805] ---[ end trace 0000000000000000 ]--- [    0.007997] RCU Tasks Rude: Setting shift to 2 and lim to 1 rcu_task_cb_adjust=1. [    0.008018] RCU Tasks Trace: Setting shift to 2 and lim to 1 rcu_task_cb_adjust=1. [    0.008043] POWER10 performance monitor hardware support registered [    0.008071] rcu: Hierarchical SRCU implementation. [    0.008078] rcu:     Max phase no-delay instances is 1000. [    0.008516] smp: Bringing up secondary CPUs ... [    0.008735] smp: Brought up 1 node, 2 CPUs ... Note: no warning observed if crashing CPU is 0, 8, 16, 24, 32, .... Code that generates warning: File: arch/powerpc/kernel/smp.c Function: update_mask_from_threadgroup ...         if (unlikely(i_group_start == -1)) {             WARN_ON_ONCE(1);             return -ENODATA;         } Thanks, Sourabh