Greeting, FYI, we noticed the following commit (built with gcc-9): commit: 1728bf6402c3d17da9271b98c5118f9448062ae9 ("drm/ast: Use managed mode-config init") https://git.kernel.org/cgit/linux/kernel/git/next/linux-next.git master in testcase: igt with following parameters: group: group_04 ucode: 0x7000019 on test machine: 16 threads Intel(R) Xeon(R) CPU D-1541 @ 2.10GHz with 48G memory caused below changes (please refer to attached dmesg/kmsg for entire log/backtrace): If you fix the issue, kindly add following tag Reported-by: kernel test robot kern :warn : [ 53.341904] WARNING: CPU: 6 PID: 1087 at drivers/gpu/drm/drm_mode_config.c:504 drm_mode_config_cleanup+0x278/0x2d0 [drm] kern :warn : [ 53.341904] Modules linked in: btrfs blake2b_generic xor zstd_decompress zstd_compress raid6_pq libcrc32c intel_rapl_msr intel_rapl_common sd_mod t10_pi sg sb_edac x86_pkg_temp_thermal intel_powerclamp ipmi_ssif coretemp kvm_intel kvm ast drm_vram_helper drm_ttm_helper ttm irqbypass drm_kms_helper crct10dif_pclmul crc32_pclmul crc32c_intel syscopyarea ghash_clmulni_intel sysfillrect sysimgblt fb_sys_fops mxm_wmi ahci acpi_ipmi intel_cstate libahci drm ipmi_si intel_uncore libata gpio_ich mei_me ipmi_devintf ioatdma intel_pch_thermal mei joydev dca ipmi_msghandler wmi acpi_pad ip_tables kern :warn : [ 53.341913] CPU: 6 PID: 1087 Comm: core_hotunplug Not tainted 5.8.0-rc2-00374-g1728bf6402c3d #1 kern :warn : [ 53.341914] Hardware name: Supermicro SYS-5018D-FN4T/X10SDV-8C-TLN4F, BIOS 1.1 03/02/2016 kern :warn : [ 53.341914] RIP: 0010:drm_mode_config_cleanup+0x278/0x2d0 [drm] kern :warn : [ 53.341915] Code: 00 e8 1c ef 15 c1 48 8b 45 00 48 39 e8 75 5b 48 8b 44 24 30 65 48 33 04 25 28 00 00 00 75 4f 48 83 c4 38 5b 5d 41 5c 41 5d c3 <0f> 0b 48 89 e6 48 89 ef e8 1b 81 ff ff eb 10 48 8b 70 48 48 c7 c7 kern :warn : [ 53.341915] RSP: 0018:ffffc900019c3d78 EFLAGS: 00010283 kern :warn : [ 53.341916] RAX: ffff888c7eeed298 RBX: ffff888c7eeed2d0 RCX: 0000000000000003 kern :warn : [ 53.341916] RDX: ffff888c7eeeb018 RSI: 000000007fffffff RDI: ffff888c7eeed2b0 kern :warn : [ 53.341916] RBP: ffff888c7eeed000 R08: ffff888c7eeed298 R09: ffffffffc0432500 kern :warn : [ 53.341917] R10: ffff888c7cec1d60 R11: 0000000000000001 R12: ffff888c7eeed2d8 kern :warn : [ 53.341917] R13: ffff888b0e3d0580 R14: dead000000000122 R15: dead000000000100 kern :warn : [ 53.341917] FS: 00007f5f1d1d9c00(0000) GS:ffff888c7fb80000(0000) knlGS:0000000000000000 kern :warn : [ 53.341918] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 kern :warn : [ 53.341918] CR2: 0000557fa36436f8 CR3: 0000000c76b88003 CR4: 00000000003606e0 kern :warn : [ 53.341918] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 kern :warn : [ 53.341919] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 kern :warn : [ 53.341919] Call Trace: kern :warn : [ 53.341919] drm_managed_release+0x9e/0x110 [drm] kern :warn : [ 53.341919] drm_dev_put+0x38/0x60 [drm] kern :warn : [ 53.341920] pci_device_remove+0x3b/0xa0 kern :warn : [ 53.341920] device_release_driver_internal+0xe4/0x1c0 kern :warn : [ 53.341920] unbind_store+0xef/0x120 kern :warn : [ 53.341921] kernfs_fop_write+0xce/0x1b0 kern :warn : [ 53.341921] vfs_write+0xdb/0x1d0 kern :warn : [ 53.341921] ksys_write+0x5f/0xe0 kern :warn : [ 53.341921] do_syscall_64+0x47/0x80 kern :warn : [ 53.341922] entry_SYSCALL_64_after_hwframe+0x44/0xa9 kern :warn : [ 53.341922] RIP: 0033:0x7f5f20c02471 kern :warn : [ 53.341922] Code: Bad RIP value. kern :warn : [ 53.341922] RSP: 002b:00007ffc96c241f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 kern :warn : [ 53.341923] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f5f20c02471 kern :warn : [ 53.341923] RDX: 000000000000000c RSI: 00007ffc96c242c9 RDI: 0000000000000004 kern :warn : [ 53.341924] RBP: 000000000000000c R08: 0000000000000000 R09: 0000557fa362afa0 kern :warn : [ 53.341924] R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffc96c242c9 kern :warn : [ 53.341924] R13: 0000000000000004 R14: 0000000000000000 R15: 0000000000000000 kern :warn : [ 53.341925] ---[ end trace 18ca678945343e21 ]--- To reproduce: git clone https://github.com/intel/lkp-tests.git cd lkp-tests bin/lkp install job.yaml # job file is attached in this email bin/lkp run job.yaml Thanks, Rong Chen