Greeting,
FYI, we noticed the following commit (built with gcc-9):
commit: c36a1cfe1ba8e83698acdf04ba59cf08370698ed ("[PATCH 4/4] drm/ttm/nouveau: move io_lru storage into driver.") url: https://github.com/0day-ci/linux/commits/Dave-Airlie/drm-amdgpu-ttm-move-vra... base: git://anongit.freedesktop.org/drm/drm-tip drm-tip
in testcase: kernel-selftests with following parameters:
group: kselftests-rseq
test-description: The kernel contains a set of "self tests" under the tools/testing/selftests/ directory. These are intended to be small unit tests to exercise individual code paths in the kernel. test-url: https://www.kernel.org/doc/Documentation/kselftest.txt
on test machine: qemu-system-x86_64 -enable-kvm -cpu SandyBridge -smp 2 -m 16G
caused below changes (please refer to attached dmesg/kmsg for entire log/backtrace):
+---------------------------------------------+------------+------------+ | | 89e1ba9e49 | c36a1cfe1b | +---------------------------------------------+------------+------------+ | boot_successes | 12 | 0 | | boot_failures | 0 | 14 | | BUG:kernel_NULL_pointer_dereference,address | 0 | 14 | | Oops:#[##] | 0 | 14 | | RIP:ttm_mem_io_lock[ttm] | 0 | 14 | | Kernel_panic-not_syncing:Fatal_exception | 0 | 14 | +---------------------------------------------+------------+------------+
If you fix the issue, kindly add following tag Reported-by: kernel test robot lkp@intel.com
[ 35.936268] BUG: kernel NULL pointer dereference, address: 0000000000000018 [ 35.936271] #PF: supervisor read access in kernel mode [ 35.936273] #PF: error_code(0x0000) - not-present page [ 35.936274] PGD 0 P4D 0 [ 35.936278] Oops: 0000 [#1] PREEMPT SMP PTI [ 35.936282] CPU: 0 PID: 157 Comm: systemd-udevd Not tainted 5.8.0-02580-gc36a1cfe1ba8e #15 [ 35.936283] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 [ 35.936293] RIP: 0010:ttm_mem_io_lock+0x33/0x40 [ttm] [ 35.936295] Code: 10 89 f3 48 85 c0 74 22 48 8b 40 18 e8 76 ba e8 fa 31 f6 48 8d 78 10 84 db 75 09 e8 27 4a ba fa 31 c0 5b c3 5b e9 7d 4a ba fa <48> 83 3c 25 18 00 00 00 00 75 d3 eb e9 66 66 66 66 90 48 8b 47 10 [ 35.936297] RSP: 0018:ffffbbcb4074f5d0 EFLAGS: 00010246 [ 35.936299] RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffffbbcb4074f6c8 [ 35.936300] RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffffa046f877c628 [ 35.936302] RBP: ffffbbcb4074f640 R08: 0000000000000001 R09: ffffffffbd994fd0 [ 35.936303] R10: ffffffffbc55eb24 R11: 00000000000054ad R12: ffffa046f8725348 [ 35.936305] R13: ffffbbcb4074f6c8 R14: ffffa046f877c628 R15: ffffa046f8725000 [ 35.936307] FS: 00007f79fae57d40(0000) GS:ffffa047afc00000(0000) knlGS:0000000000000000 [ 35.936309] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 35.936310] CR2: 0000000000000018 CR3: 00000003797ce000 CR4: 00000000000406f0 [ 35.936316] Call Trace: [ 35.936325] ttm_bo_handle_move_mem+0x53/0x4f0 [ttm] [ 35.936335] ttm_bo_validate+0x169/0x1b0 [ttm] [ 35.936340] ? mark_held_locks+0x2d/0x80 [ 35.936350] drm_gem_vram_pin_locked+0x84/0x1d0 [drm_vram_helper] [ 35.936356] drm_gem_vram_pin+0x40/0xf0 [drm_vram_helper] [ 35.936361] drm_gem_vram_plane_helper_prepare_fb+0x2e/0x80 [drm_vram_helper] [ 35.936367] drm_atomic_helper_prepare_planes+0x8a/0x110 [ 35.936371] drm_atomic_helper_commit+0x91/0x160 [ 35.936376] drm_client_modeset_commit_atomic+0x231/0x270 [ 35.936388] drm_client_modeset_commit_locked+0x57/0x190 [ 35.936391] drm_client_modeset_commit+0x24/0x40 [ 35.936396] __drm_fb_helper_restore_fbdev_mode_unlocked+0x96/0xc0 [ 35.936400] drm_fb_helper_set_par+0x3c/0x50 [ 35.936404] fbcon_init+0x2b2/0x5f0 [ 35.936412] visual_init+0xce/0x130 [ 35.936416] do_bind_con_driver+0x1bc/0x2b0 [ 35.936422] do_take_over_console+0x115/0x180 [ 35.936428] do_fbcon_takeover+0x58/0xb0 [ 35.936430] register_framebuffer+0x1ee/0x300 [ 35.936442] __drm_fb_helper_initial_config_and_unlock+0x94/0xc0 [ 35.936446] drm_fbdev_client_hotplug+0xde/0x190 [ 35.936450] drm_fbdev_generic_setup+0xad/0x170 [ 35.936456] bochs_pci_probe+0x133/0x160 [bochs_drm] [ 35.936460] local_pci_probe+0x42/0x80 [ 35.936464] pci_device_probe+0x107/0x1a0 [ 35.936471] really_probe+0x147/0x3c0 [ 35.936475] driver_probe_device+0xe1/0x150 [ 35.936479] device_driver_attach+0x53/0x60 [ 35.936482] __driver_attach+0x8c/0x150 [ 35.936484] ? device_driver_attach+0x60/0x60 [ 35.936487] ? device_driver_attach+0x60/0x60 [ 35.936489] bus_for_each_dev+0x7b/0xc0 [ 35.936494] bus_add_driver+0x150/0x1f0 [ 35.936498] driver_register+0x6c/0xc0 [ 35.936501] ? 0xffffffffc0537000 [ 35.936504] do_one_initcall+0x5d/0x330 [ 35.936508] ? do_init_module+0x23/0x230 [ 35.936512] ? rcu_read_lock_sched_held+0x52/0x90 [ 35.936516] ? kmem_cache_alloc_trace+0x2aa/0x2e0 [ 35.936521] do_init_module+0x5c/0x230 [ 35.936523] load_module+0x1430/0x1660 [ 35.936539] ? __do_sys_finit_module+0xaa/0x110 [ 35.936541] __do_sys_finit_module+0xaa/0x110 [ 35.936554] do_syscall_64+0x57/0xb0 [ 35.936559] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 35.936561] RIP: 0033:0x7f79fb641f59 [ 35.936564] Code: 00 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 07 6f 0c 00 f7 d8 64 89 01 48 [ 35.936566] RSP: 002b:00007fff46de1208 EFLAGS: 00000246 ORIG_RAX: 0000000000000139 [ 35.936568] RAX: ffffffffffffffda RBX: 000055fb6b100da0 RCX: 00007f79fb641f59 [ 35.936569] RDX: 0000000000000000 RSI: 00007f79fb546cad RDI: 0000000000000011 [ 35.936571] RBP: 00007f79fb546cad R08: 0000000000000000 R09: 0000000000000000 [ 35.936572] R10: 0000000000000011 R11: 0000000000000246 R12: 0000000000000000 [ 35.936574] R13: 000055fb6b0f72b0 R14: 0000000000020000 R15: 000055fb6b100da0 [ 35.936582] Modules linked in: bochs_drm(+) drm_vram_helper drm_ttm_helper ttm crypto_simd snd_timer snd cryptd parport_pc glue_helper ata_piix joydev parport soundcore libata serio_raw pcspkr floppy i2c_piix4 ipmi_devintf ipmi_msghandler ip_tables [ 35.936597] CR2: 0000000000000018 [ 35.936628] ---[ end trace 0eac1a886c6bb87d ]---
To reproduce:
# build kernel cd linux cp config-5.8.0-02580-gc36a1cfe1ba8e .config make HOSTCC=gcc-9 CC=gcc-9 ARCH=x86_64 olddefconfig prepare modules_prepare bzImage
git clone https://github.com/intel/lkp-tests.git cd lkp-tests bin/lkp qemu -k <bzImage> job-script # job-script is attached in this email
Thanks, lkp