On Tue, Sep 14, 2021 at 09:03:38AM -0700, Guenter Roeck wrote:

Hi,

I see the following crashes in v4.14.y-queue and v4.19.y-queue. Please let me know if I need to bisect.

Thanks, Guenter

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v4.14.y:

BUG: Kernel NULL pointer dereference at 0x000000c0 Faulting instruction address: 0xc0069d04 Oops: Kernel access of bad area, sig: 11 [#1] BE MPC8544 DS Modules linked in: CPU: 0 PID: 473 Comm: kworker/0:1 Not tainted 4.14.247-rc1-00101-gd73a5c779001 #1 Workqueue: events __blk_release_queue task: ce510ea0 task.stack: ce1f0000 NIP: c0069d04 LR: c0565384 CTR: c0069cd4 REGS: ce1f1d30 TRAP: 0300 Not tainted (4.14.247-rc1-00101-gd73a5c779001) MSR: 00029000 <CE,EE,ME> CR: 42002402 XER: 20000000 DEAR: 000000c0 ESR: 00000000 GPR00: c056951c ce1f1de0 ce510ea0 ce2e1530 ceac0000 00000000 ce511320 f2050c9c GPR08: 00000001 5a5a5a5a cea752e8 97cae497 22002402 00000000 c0074dac ce23a518 GPR16: 00000000 00000000 00000000 00000000 00000000 00000000 c0f661c0 fffffef7 GPR24: c1010000 ce1f0000 00000000 00000000 ce2e1530 00000000 ce2e1520 ce2e1530 NIP [c0069d04] pwq_unbound_release_workfn+0x30/0x184 LR [c0565384] blk_mq_free_rqs+0x90/0x130 Call Trace: [ce1f1de0] [c056a3a8] blk_mq_exit_sched+0xc0/0xe8 (unreliable) [ce1f1e00] [ceaa7ea8] 0xceaa7ea8 [ce1f1e20] [c056951c] blk_mq_sched_tags_teardown+0x64/0xa0 [ce1f1e40] [c056a3b0] blk_mq_exit_sched+0xc8/0xe8 [ce1f1e60] [c054a24c] elevator_exit+0x98/0xc0 [ce1f1e80] [c05581cc] __blk_release_queue+0x58/0x13c [ce1f1e90] [c006e8a4] process_one_work+0x2e4/0x6bc [ce1f1ed0] [c006f18c] worker_thread+0x17c/0x46c [ce1f1f10] [c0074ecc] kthread+0x120/0x15c [ce1f1f40] [c001345c] ret_from_kernel_thread+0x5c/0x64 Instruction dump: 9421ffe0 93c10018 3bc3fff0 93e1001c 7c7f1b78 9361000c 93a10014 8123fff0 83a3ff94 8363ff90 7c1e4840 418200f4 <813d00c0> 71290002 41820144 93810010 ---[ end trace be33d503d2af084b ]---

BUG: Kernel NULL pointer dereference at 0x00000180 Faulting instruction address: 0xc00000000006e5c4 Oops: Kernel access of bad area, sig: 11 [#1] BE SMP NR_CPUS=24 QEMU e500 Modules linked in: CPU: 0 PID: 498 Comm: kworker/0:1 Not tainted 4.14.247-rc1-00101-gd73a5c779001 #1 Workqueue: events .__blk_release_queue task: c00000003e1ddd40 task.stack: c00000003e540000 NIP: c00000000006e5c4 LR: c0000000005dc204 CTR: c00000000006e594 REGS: c00000003e543530 TRAP: 0300 Not tainted (4.14.247-rc1-00101-gd73a5c779001) MSR: 0000000080009000 <EE,ME> CR: 24002844 XER: 20000000 DEAR: 0000000000000180 ESR: 0000000000000000 SOFTE: 1 GPR00: c0000000005e0dfc c00000003e5437b0 c000000001380a00 c00000000712bba8 GPR04: c000000007180000 0000000000000000 000000004563074d 00000000857e8f62 GPR08: 000000003de9d000 0000000000000000 c00000000006e594 c0000000011d0a00 GPR12: 0000000044002842 c00000003fff5000 c00000000007ac78 c00000003e3d1af8 GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 GPR20: 0000000000000000 0000000000000000 c00000003f00b140 c00000000138a940 GPR24: 0000000000000000 c00000000124a640 0000000000000000 0000000000000000 GPR28: c00000000712bba8 c00000000712bb88 0000000000000000 c00000000712bba8 NIP [c00000000006e5c4] .pwq_unbound_release_workfn+0x30/0x1c0 LR [c0000000005dc204] .blk_mq_free_rqs+0x9c/0x14c Call Trace: [c00000003e5437b0] [c00000003e543840] 0xc00000003e543840 (unreliable) [c00000003e543850] [c000000000218980] .kfree+0xe4/0x3f4 [c00000003e5438f0] [c0000000005e0dfc] .blk_mq_sched_free_tags+0x28/0x54 [c00000003e543970] [c0000000005e0f1c] .blk_mq_sched_tags_teardown+0x48/0x78 [c00000003e543a00] [c0000000005e2030] .blk_mq_exit_sched+0xf4/0x114 [c00000003e543aa0] [c0000000005be008] .elevator_exit+0xb8/0xf0 [c00000003e543b30] [c0000000005cdba8] .__blk_release_queue+0x64/0x190 [c00000003e543bb0] [c000000000072604] .process_one_work+0x324/0x894 [c00000003e543c90] [c000000000072be0] .worker_thread+0x6c/0x4f0 [c00000003e543d70] [c00000000007ae28] .kthread+0x1b0/0x1b8 [c00000003e543e30] [c000000000000a00] .ret_from_kernel_thread+0x58/0xd8 Instruction dump: fba1ffe8 3ba3ffe0 fbe1fff8 7c7f1b78 fb61ffd8 fbc1fff0 f821ff61 e923ffe0 ebc3ff78 7fbd4840 eb63ff70 419e0124 <813e0180> 71290002 41820180 7c0802a6 ---[ end trace a1c724264250a495 ]---

v4.19.y:

BUG: Unable to handle kernel data access at 0x6b6b6b8f Faulting instruction address: 0xc05fef28 Oops: Kernel access of bad area, sig: 11 [#1] BE SMP NR_CPUS=24 MPC8544 DS Modules linked in: CPU: 0 PID: 21 Comm: kworker/0:1 Tainted: G W 4.19.207-rc1-00121-gae1a50dc8893 #1 Workqueue: events __blk_release_queue NIP: c05fef28 LR: c0603e3c CTR: 00000000 REGS: ce143d30 TRAP: 0300 Tainted: G W (4.19.207-rc1-00121-gae1a50dc8893) MSR: 00029000 <CE,EE,ME> CR: 84002404 XER: 00000000 DEAR: 6b6b6b8f ESR: 00000000 GPR00: c0603e3c ce143de0 ce131ee0 cea4e8a0 cea4a890 00000000 00021000 00000000 GPR08: 00000001 6b6b6b6b ceb26008 00001780 44002802 00000000 c0080784 ce113d88 GPR16: 00000000 00000000 00000000 00000000 c10b0e2c c10b0e04 fffffef7 00000402 GPR24: c1160000 00000000 c11627ec 00000000 cea4e8a0 cea591d8 cea4a890 00000001 NIP [c05fef28] blk_mq_free_rqs+0x34/0x130 LR [c0603e3c] blk_mq_sched_tags_teardown+0x64/0xa0 Call Trace: [ce143e00] [c0603e3c] blk_mq_sched_tags_teardown+0x64/0xa0 [ce143e20] [c06046a4] blk_mq_exit_sched+0xc8/0xe8 [ce143e40] [c05e1bcc] elevator_exit+0x98/0xc0 [ce143e60] [c05ea85c] blk_exit_queue+0x30/0x50 [ce143e70] [c05f09f0] __blk_release_queue+0x50/0x15c [ce143e80] [c0079d9c] process_one_work+0x2b0/0x6b0 [ce143ec0] [c007a6f0] worker_thread+0x19c/0x49c [ce143f10] [c00808c4] kthread+0x140/0x17c [ce143f40] [c001534c] ret_from_kernel_thread+0x14/0x1c Instruction dump: 7c0802a6 93c10018 7c9e2378 90010024 93810010 93a10014 93e1001c 8124005c 2c090000 41820084 81230004 7c7c1b78 <81290024> 2c090000 41820070 81240000 ---[ end trace df2545c1cd678853 ]---

Bisection would be great to track this down if at all possible.

thanks,

greg k-h