On Tue, Oct 10, 2023 at 02:38:40PM +0530, Sourabh Jain wrote: > 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 > > <SF,VEC,VSX,EE,PR,FP,ME,IR,DR,RI,LE> 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@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx) (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 <SF,ME,IR,DR,RI,LE> 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 */ -- 2.31.1 _______________________________________________ kexec mailing list kexec@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/kexec