While running kselftest memfd fuse_test test case kernel BUG found on i386 kernel running x86_64 device running Linux-next 5.6.0-next-20200408 kernel version. Linux version 5.6.0-next-20200408 (oe-user@oe-host) (gcc version 7.3.0 (GCC), GNU ld (GNU Binutils) 2.30.0.20180208) #1 SMP Wed Apr 8 04:48:57 UTC 2020 <> [ 452.885727] kselftest: Running tests in memfd [ 452.974683] audit: type=1701 audit(1586366703.840:87435): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=kernel pid=13617 comm=\"fuse_test\" exe=\"/opt/kselftests/default-in-kernel/memfd/fuse_test\" sig=6 res=1 [ 452.975400] BUG: kernel NULL pointer dereference, address: 00000041 [ 452.999344] #PF: supervisor read access in kernel mode [ 453.004475] #PF: error_code(0x0000) - not-present page [ 453.009605] *pde = 00000000 [ 453.012482] Oops: 0000 [#2] SMP [ 453.015619] CPU: 1 PID: 13617 Comm: fuse_test Tainted: G D W 5.6.0-next-20200408 #1 [ 453.024388] Hardware name: Supermicro SYS-5019S-ML/X11SSH-F, BIOS 2.0b 07/27/2017 [ 453.031862] EIP: __kmalloc+0xa2/0x310 [ 453.035525] Code: 9c 01 00 00 89 75 e4 8b 07 64 8b 50 04 64 03 05 d8 92 bd cb 8b 08 85 c9 89 4d f0 0f 84 07 02 00 00 8b 75 f0 8b 47 14 8d 4a 01 <8b> 1c 06 89 f0 8b 37 64 0f c7 0e 75 d0 8b 75 e4 8b 47 14 0f 18 04 [ 453.054264] EAX: 00000040 EBX: 00000cc0 ECX: 000045c3 EDX: 000045c2 [ 453.060519] ESI: 00000001 EDI: f5403680 EBP: e1effcb8 ESP: e1effc98 [ 453.066776] DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068 EFLAGS: 00010202 [ 453.073555] CR0: 80050033 CR2: 00000041 CR3: 216ee000 CR4: 003406d0 [ 453.079812] DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000 [ 453.086067] DR6: fffe0ff0 DR7: 00000400 [ 453.089898] Call Trace: [ 453.092345] ? elf_core_dump+0x520/0x16a0 [ 453.096357] elf_core_dump+0x520/0x16a0 [ 453.100215] ? kmem_cache_free+0xeb/0x2e0 [ 453.104236] do_coredump+0x617/0x1070 [ 453.107911] ? trace_hardirqs_off+0x1d/0xf0 [ 453.112095] ? lock_acquire+0x81/0x320 [ 453.115850] get_signal+0xaa8/0xb40 [ 453.119341] do_signal+0x23/0x630 [ 453.122659] ? _raw_spin_unlock_irq+0x22/0x30 [ 453.127019] ? __set_current_blocked+0x47/0x50 [ 453.131468] exit_to_usermode_loop+0x6a/0xd0 [ 453.135736] do_fast_syscall_32+0x297/0x330 [ 453.139914] entry_SYSENTER_32+0xaa/0x102 [ 453.143916] EIP: 0xb7f1bce1 [ 453.146706] Code: 5e 5d c3 8d b6 00 00 00 00 b8 40 42 0f 00 eb c1 8b 04 24 c3 8b 1c 24 c3 8b 34 24 c3 8b 3c 24 c3 90 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d 76 00 58 b8 77 00 00 00 cd 80 90 8d 76 [ 453.165444] EAX: 00000000 EBX: 00000002 ECX: bfb63cc0 EDX: 00000000 [ 453.171700] ESI: 00000008 EDI: 00000000 EBP: bfb63cc0 ESP: bfb63cb0 [ 453.177957] DS: 007b ES: 007b FS: 0000 GS: 0033 SS: 007b EFLAGS: 00000246 [ 453.184737] Modules linked in: test_printf(+) cls_bpf sch_fq sch_ingress algif_hash x86_pkg_temp_thermal fuse [last unloaded: test_strscpy] [ 453.197292] CR2: 0000000000000041 [ 453.200612] ---[ end trace 4ae6b60cdb1cebfa ]--- [ 453.205222] EIP: ida_free+0x61/0x130 [ 453.208794] Code: 00 c7 45 e8 00 00 00 00 c7 45 ec 00 00 00 00 0f 88 c4 00 00 00 89 d3 e8 6d 60 8a 00 89 c7 8d 45 d8 e8 c3 1a 01 00 a8 01 75 3f <0f> a3 30 72 72 8b 45 d8 89 fa e8 40 62 8a 00 53 68 e8 db 80 cb e8 [ 453.227529] EAX: 00000000 EBX: 00000000 ECX: f37c3540 EDX: 00000000 [ 453.233787] ESI: 00000000 EDI: 00000246 EBP: e1e75cdc ESP: e1e75cb0 [ 453.240043] DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068 EFLAGS: 00010046 [ 453.246820] CR0: 80050033 CR2: 00000041 CR3: 216ee000 CR4: 003406d0 [ 453.253077] DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000 [ 453.259334] DR6: fffe0ff0 DR7: 00000400 [ 453.263176] BUG: sleeping function called from invalid context at /usr/src/kernel/include/linux/percpu-rwsem.h:49 [ 453.273445] in_atomic(): 0, irqs_disabled(): 1, non_block: 0, pid: 13617, name: fuse_test [ 453.281615] INFO: lockdep is turned off. [ 453.285533] irq event stamp: 0 [ 453.288585] hardirqs last enabled at (0): [<00000000>] 0x0 [ 453.294173] hardirqs last disabled at (0): [<ca6ed9ea>] copy_process+0x3ea/0x17d0 [ 453.301672] softirqs last enabled at (0): [<ca6ed9ea>] copy_process+0x3ea/0x17d0 [ 453.309172] softirqs last disabled at (0): [<00000000>] 0x0 [ 453.314741] CPU: 1 PID: 13617 Comm: fuse_test Tainted: G D W 5.6.0-next-20200408 #1 [ 453.323519] Hardware name: Supermicro SYS-5019S-ML/X11SSH-F, BIOS 2.0b 07/27/2017 [ 453.330988] Call Trace: [ 453.333435] dump_stack+0x6e/0x96 [ 453.336754] ___might_sleep+0x14d/0x240 [ 453.340592] __might_sleep+0x33/0x80 [ 453.344173] exit_signals+0x2a/0x2d0 [ 453.347750] do_exit+0x8e/0xb40 [ 453.350889] ? exit_to_usermode_loop+0x6a/0xd0 [ 453.355336] rewind_stack_do_exit+0x11/0x13 [ 453.359519] EIP: 0xb7f1bce1 [ 453.362308] Code: 5e 5d c3 8d b6 00 00 00 00 b8 40 42 0f 00 eb c1 8b 04 24 c3 8b 1c 24 c3 8b 34 24 c3 8b 3c 24 c3 90 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d 76 00 58 b8 77 00 00 00 cd 80 90 8d 76 [ 453.381044] EAX: 00000000 EBX: 00000002 ECX: bfb63cc0 EDX: 00000000 [ 453.387303] ESI: 00000008 EDI: 00000000 EBP: bfb63cc0 ESP: bfb63cb0 [ 453.393560] DS: 007b ES: 007b FS: 0000 GS: 0033 SS: 007b EFLAGS: 00000246 metadata: git branch: master git repo: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git kernel-config: http://snapshots.linaro.org/openembedded/lkft/lkft/sumo/intel-core2-32/lkft/linux-next/745/config Full test log, https://lkft.validation.linaro.org/scheduler/job/1352031#L10567 -- Linaro LKFT https://lkft.linaro.org