Hello Below NULL pointer was triggered[2] with blktests block/029 on latest linux-block/for-next, pls check it. [1] 9b3b463f3955 (HEAD -> for-next, origin/for-next) Merge branch 'for-5.16/block' into for-next [2] [ 110.508269] run blktests block/029 at 2021-10-26 05:29:11 [ 110.535182] null_blk: module loaded [ 110.674174] Kernel attempted to read user page (d8) - exploit attempt? (uid: 0) [ 110.674212] BUG: Kernel NULL pointer dereference on read at 0x000000d8 [ 110.674236] Faulting instruction address: 0xc0000000009414c4 [ 110.674251] Oops: Kernel access of bad area, sig: 11 [#1] [ 110.674272] LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=2048 NUMA PowerNV [ 110.674308] Modules linked in: null_blk rfkill sunrpc joydev ofpart ses enclosure scsi_transport_sas i40e at24 powernv_flash mtd tpm_i2c_nuvoton regmap_i2c ipmi_powernv rtc_opal crct10dif_vpmsum opal_prd ipmi_devintf i2c_opal ipmi_msghandler fuse zram ip_tables xfs ast i2c_algo_bit drm_vram_helper drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops cec drm_ttm_helper ttm drm vmx_crypto crc32c_vpmsum i2c_core aacraid drm_panel_orientation_quirks [ 110.674485] CPU: 60 PID: 3469 Comm: check Not tainted 5.15.0-rc6+ #3 [ 110.674520] NIP: c0000000009414c4 LR: c000000000941638 CTR: 0000000000000000 [ 110.674556] REGS: c00000003aea77c0 TRAP: 0300 Not tainted (5.15.0-rc6+) [ 110.674580] MSR: 900000000280b033 <SF,HV,VEC,VSX,EE,FP,ME,IR,DR,RI,LE> CR: 84428482 XER: 00000006 [ 110.674634] CFAR: c000000000941648 DAR: 00000000000000d8 DSISR: 40000000 IRQMASK: 0 [ 110.674634] GPR00: c000000000941638 c00000003aea7a60 c0000000028a9a00 c00000001ad8a8c0 [ 110.674634] GPR04: c000000089287e00 0000000000000001 00000000ffffffff ffffffffffffffff [ 110.674634] GPR08: 00000000000000d8 0000000000000000 00000000000000d8 0000000000000400 [ 110.674634] GPR12: 0000000000008000 c000000ffff9e600 c00000001ac416c0 0000000000000000 [ 110.674634] GPR16: 0000000000000001 0000000000000001 0000000000000000 c009dfffff94f300 [ 110.674634] GPR20: 0000000000000000 0000000000000000 c0000000028e72b8 c0000000028e78a0 [ 110.674634] GPR24: 0000000000000001 0000000000000008 c0000000aaa53838 c009dfffff94f388 [ 110.674634] GPR28: c00000009d527698 c009dfffff94f3a0 0000000000000002 c0000000aaa53858 [ 110.674942] NIP [c0000000009414c4] blk_mq_map_swqueue+0x1a4/0x490 [ 110.674982] LR [c000000000941638] blk_mq_map_swqueue+0x318/0x490 [ 110.675021] Call Trace: [ 110.675038] [c00000003aea7a60] [c000000000941638] blk_mq_map_swqueue+0x318/0x490 (unreliable) [ 110.675080] [c00000003aea7b10] [c0000000009420e4] blk_mq_update_nr_hw_queues+0x244/0x480 [ 110.675128] [c00000003aea7bd0] [c00800000f3e2d60] nullb_device_submit_queues_store+0x98/0x120 [null_blk] [ 110.675182] [c00000003aea7c20] [c000000000648aa8] configfs_write_iter+0x118/0x1e0 [ 110.675224] [c00000003aea7c70] [c000000000521494] new_sync_write+0x124/0x1b0 [ 110.675281] [c00000003aea7d10] [c000000000524794] vfs_write+0x2c4/0x390 [ 110.675299] [c00000003aea7d60] [c000000000524b08] ksys_write+0x78/0x130 [ 110.675316] [c00000003aea7db0] [c00000000002d648] system_call_exception+0x188/0x360 [ 110.675335] [c00000003aea7e10] [c00000000000c1e8] system_call_vectored_common+0xe8/0x278 [ 110.675355] --- interrupt: 3000 at 0x7fffa1aefee4 [ 110.675367] NIP: 00007fffa1aefee4 LR: 0000000000000000 CTR: 0000000000000000 [ 110.675393] REGS: c00000003aea7e80 TRAP: 3000 Not tainted (5.15.0-rc6+) [ 110.675429] MSR: 900000000280f033 <SF,HV,VEC,VSX,EE,PR,FP,ME,IR,DR,RI,LE> CR: 48422488 XER: 00000000 [ 110.675482] IRQMASK: 0 [ 110.675482] GPR00: 0000000000000004 00007fffc592dd30 00007fffa1be7000 0000000000000001 [ 110.675482] GPR04: 0000000143297fc0 0000000000000002 0000000000000010 00000001432bd791 [ 110.675482] GPR08: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 [ 110.675482] GPR12: 0000000000000000 00007fffa1d2afa0 0000000000000000 0000000000000000 [ 110.675482] GPR16: 000000010dfd87b8 000000010dfd94d4 0000000020000000 000000010deeae80 [ 110.675482] GPR20: 0000000000000000 00007fffc592df54 000000010df83128 000000010dfd89bc [ 110.675482] GPR24: 000000010dfd8a50 0000000000000000 0000000143297fc0 0000000000000002 [ 110.675482] GPR28: 0000000000000002 00007fffa1be16d8 0000000143297fc0 0000000000000002 [ 110.675718] NIP [00007fffa1aefee4] 0x7fffa1aefee4 [ 110.675750] LR [0000000000000000] 0x0 [ 110.675769] --- interrupt: 3000 [ 110.675789] Instruction dump: [ 110.675798] 2c290000 41820168 e91c0600 7bc926e4 e95c0048 7d28482a 7d29a82e 79291f24 [ 110.675845] 7d2a482a f93d0000 390900d8 7d489214 <7d08a02a> 7d088839 4082004c 7d0050a8 [ 110.675885] ---[ end trace b9b604499c6b5b71 ]--- [ 110.814135] [ 111.814148] Kernel panic - not syncing: Fatal exception [ 113.674122] ---[ end Kernel panic - not syncing: Fatal exception ]--- -- Best Regards, Yi Zhang