From: kernel test robot <oliver.sang@intel.com>
To: Luca Ceresoli <luca.ceresoli@bootlin.com>
Cc: <oe-lkp@lists.linux.dev>, <lkp@intel.com>,
<dri-devel@lists.freedesktop.org>,
Maarten Lankhorst <maarten.lankhorst@linux.intel.com>,
Maxime Ripard <mripard@kernel.org>,
Thomas Zimmermann <tzimmermann@suse.de>,
David Airlie <airlied@gmail.com>, Simona Vetter <simona@ffwll.ch>,
Andrzej Hajda <andrzej.hajda@intel.com>,
Neil Armstrong <neil.armstrong@linaro.org>,
Robert Foss <rfoss@kernel.org>,
Laurent Pinchart <Laurent.pinchart@ideasonboard.com>,
Jonas Karlman <jonas@kwiboo.se>,
Jernej Skrabec <jernej.skrabec@gmail.com>,
Hui Pu <Hui.Pu@gehealthcare.com>,
Thomas Petazzoni <thomas.petazzoni@bootlin.com>,
<linux-kernel@vger.kernel.org>,
Luca Ceresoli <luca.ceresoli@bootlin.com>,
<oliver.sang@intel.com>
Subject: Re: [PATCH 4/7] drm/bridge: lock the encoder chain in scoped for_each loops
Date: Tue, 30 Sep 2025 14:16:23 +0800 [thread overview]
Message-ID: <202509301358.38036b85-lkp@intel.com> (raw)
In-Reply-To: <20250926-drm-bridge-alloc-encoder-chain-mutex-v1-4-23b62c47356a@bootlin.com>
Hello,
kernel test robot noticed "BUG:workqueue_lockup-pool" on:
commit: a3ae9f413a9785cbf472a3168131747f79722d31 ("[PATCH 4/7] drm/bridge: lock the encoder chain in scoped for_each loops")
url: https://github.com/intel-lab-lkp/linux/commits/Luca-Ceresoli/drm-encoder-add-mutex-to-protect-the-bridge-chain/20250927-000253
patch link: https://lore.kernel.org/all/20250926-drm-bridge-alloc-encoder-chain-mutex-v1-4-23b62c47356a@bootlin.com/
patch subject: [PATCH 4/7] drm/bridge: lock the encoder chain in scoped for_each loops
in testcase: boot
config: x86_64-randconfig-071-20250929
compiler: clang-20
test machine: qemu-system-x86_64 -enable-kvm -cpu SandyBridge -smp 2 -m 16G
(please refer to attached dmesg/kmsg for entire log/backtrace)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <oliver.sang@intel.com>
| Closes: https://lore.kernel.org/oe-lkp/202509301358.38036b85-lkp@intel.com
[ 63.465088][ C0] BUG: workqueue lockup - pool cpus=1 node=0 flags=0x0 nice=0 stuck for 45s!
[ 63.465385][ C0] Showing busy workqueues and worker pools:
[ 63.465405][ C0] workqueue mm_percpu_wq: flags=0x8
[ 63.465454][ C0] pwq 6: cpus=1 node=0 flags=0x0 nice=0 active=1 refcnt=2
[ 63.465500][ C0] pending: vmstat_update
[ 63.465696][ C0] Showing backtraces of running workers in stalled CPU-bound worker pools:
[ 94.185049][ C0] BUG: workqueue lockup - pool cpus=1 node=0 flags=0x0 nice=0 stuck for 76s!
[ 94.185123][ C0] Showing busy workqueues and worker pools:
[ 94.185136][ C0] workqueue mm_percpu_wq: flags=0x8
[ 94.185146][ C0] pwq 6: cpus=1 node=0 flags=0x0 nice=0 active=1 refcnt=2
[ 94.185169][ C0] pending: vmstat_update
[ 94.185278][ C0] Showing backtraces of running workers in stalled CPU-bound worker pools:
[ 124.905021][ C0] BUG: workqueue lockup - pool cpus=1 node=0 flags=0x0 nice=0 stuck for 107s!
[ 124.905073][ C0] Showing busy workqueues and worker pools:
[ 124.905080][ C0] workqueue mm_percpu_wq: flags=0x8
[ 124.905087][ C0] pwq 6: cpus=1 node=0 flags=0x0 nice=0 active=1 refcnt=2
[ 124.905100][ C0] pending: vmstat_update
[ 124.905172][ C0] Showing backtraces of running workers in stalled CPU-bound worker pools:
[ 155.624991][ C0] BUG: workqueue lockup - pool cpus=1 node=0 flags=0x0 nice=0 stuck for 137s!
[ 155.625049][ C0] Showing busy workqueues and worker pools:
[ 155.625057][ C0] workqueue mm_percpu_wq: flags=0x8
[ 155.625065][ C0] pwq 6: cpus=1 node=0 flags=0x0 nice=0 active=1 refcnt=2
[ 155.625081][ C0] pending: vmstat_update
[ 155.625161][ C0] Showing backtraces of running workers in stalled CPU-bound worker pools:
[ 186.345006][ C0] BUG: workqueue lockup - pool cpus=1 node=0 flags=0x0 nice=0 stuck for 168s!
[ 186.345099][ C0] Showing busy workqueues and worker pools:
[ 186.345111][ C0] workqueue mm_percpu_wq: flags=0x8
[ 186.345123][ C0] pwq 6: cpus=1 node=0 flags=0x0 nice=0 active=1 refcnt=2
[ 186.345151][ C0] pending: vmstat_update
[ 186.345277][ C0] Showing backtraces of running workers in stalled CPU-bound worker pools:
[ 217.065070][ C0] BUG: workqueue lockup - pool cpus=1 node=0 flags=0x0 nice=0 stuck for 199s!
[ 217.065206][ C0] Showing busy workqueues and worker pools:
[ 217.065227][ C0] workqueue mm_percpu_wq: flags=0x8
[ 217.065247][ C0] pwq 6: cpus=1 node=0 flags=0x0 nice=0 active=1 refcnt=2
[ 217.065290][ C0] pending: vmstat_update
[ 217.065477][ C0] Showing backtraces of running workers in stalled CPU-bound worker pools:
[ 247.785028][ C0] BUG: workqueue lockup - pool cpus=1 node=0 flags=0x0 nice=0 stuck for 230s!
[ 247.785093][ C0] Showing busy workqueues and worker pools:
[ 247.785104][ C0] workqueue mm_percpu_wq: flags=0x8
[ 247.785112][ C0] pwq 6: cpus=1 node=0 flags=0x0 nice=0 active=1 refcnt=2
[ 247.785130][ C0] pending: vmstat_update
[ 247.785223][ C0] Showing backtraces of running workers in stalled CPU-bound worker pools:
[ 278.504990][ C0] BUG: workqueue lockup - pool cpus=1 node=0 flags=0x0 nice=0 stuck for 260s!
[ 278.505051][ C0] Showing busy workqueues and worker pools:
[ 278.505062][ C0] workqueue mm_percpu_wq: flags=0x8
[ 278.505069][ C0] pwq 6: cpus=1 node=0 flags=0x0 nice=0 active=1 refcnt=2
[ 278.505086][ C0] pending: vmstat_update
[ 278.505169][ C0] Showing backtraces of running workers in stalled CPU-bound worker pools:
[ 309.224985][ C0] BUG: workqueue lockup - pool cpus=1 node=0 flags=0x0 nice=0 stuck for 291s!
[ 309.225073][ C0] Showing busy workqueues and worker pools:
[ 309.225085][ C0] workqueue mm_percpu_wq: flags=0x8
[ 309.225097][ C0] pwq 6: cpus=1 node=0 flags=0x0 nice=0 active=1 refcnt=2
[ 309.225122][ C0] pending: vmstat_update
[ 309.225238][ C0] Showing backtraces of running workers in stalled CPU-bound worker pools:
[ 339.944986][ C0] BUG: workqueue lockup - pool cpus=1 node=0 flags=0x0 nice=0 stuck for 322s!
[ 339.945076][ C0] Showing busy workqueues and worker pools:
[ 339.945089][ C0] workqueue mm_percpu_wq: flags=0x8
[ 339.945102][ C0] pwq 6: cpus=1 node=0 flags=0x0 nice=0 active=1 refcnt=2
[ 339.945130][ C0] pending: vmstat_update
[ 339.945258][ C0] Showing backtraces of running workers in stalled CPU-bound worker pools:
[ 370.665059][ C0] BUG: workqueue lockup - pool cpus=1 node=0 flags=0x0 nice=0 stuck for 352s!
[ 370.665192][ C0] Showing busy workqueues and worker pools:
[ 370.665212][ C0] workqueue mm_percpu_wq: flags=0x8
[ 370.665233][ C0] pwq 6: cpus=1 node=0 flags=0x0 nice=0 active=1 refcnt=2
[ 370.665276][ C0] pending: vmstat_update
[ 370.665467][ C0] Showing backtraces of running workers in stalled CPU-bound worker pools:
[ 401.385016][ C0] BUG: workqueue lockup - pool cpus=1 node=0 flags=0x0 nice=0 stuck for 383s!
[ 401.385074][ C0] Showing busy workqueues and worker pools:
[ 401.385085][ C0] workqueue mm_percpu_wq: flags=0x8
[ 401.385092][ C0] pwq 6: cpus=1 node=0 flags=0x0 nice=0 active=1 refcnt=2
[ 401.385108][ C0] pending: vmstat_update
[ 401.385195][ C0] Showing backtraces of running workers in stalled CPU-bound worker pools:
[ 432.104963][ C0] BUG: workqueue lockup - pool cpus=1 node=0 flags=0x0 nice=0 stuck for 414s!
[ 432.105013][ C0] Showing busy workqueues and worker pools:
[ 432.105021][ C0] workqueue mm_percpu_wq: flags=0x8
[ 432.105027][ C0] pwq 6: cpus=1 node=0 flags=0x0 nice=0 active=1 refcnt=2
[ 432.105041][ C0] pending: vmstat_update
[ 432.105111][ C0] Showing backtraces of running workers in stalled CPU-bound worker pools:
[ 462.824979][ C0] BUG: workqueue lockup - pool cpus=1 node=0 flags=0x0 nice=0 stuck for 445s!
[ 462.825065][ C0] Showing busy workqueues and worker pools:
[ 462.825076][ C0] workqueue mm_percpu_wq: flags=0x8
[ 462.825087][ C0] pwq 6: cpus=1 node=0 flags=0x0 nice=0 active=1 refcnt=2
[ 462.825112][ C0] pending: vmstat_update
[ 462.825229][ C0] Showing backtraces of running workers in stalled CPU-bound worker pools:
[ 493.544976][ C0] BUG: workqueue lockup - pool cpus=1 node=0 flags=0x0 nice=0 stuck for 475s!
[ 493.545072][ C0] Showing busy workqueues and worker pools:
[ 493.545084][ C0] workqueue mm_percpu_wq: flags=0x8
[ 493.545096][ C0] pwq 6: cpus=1 node=0 flags=0x0 nice=0 active=1 refcnt=2
[ 493.545124][ C0] pending: vmstat_update
[ 493.545252][ C0] Showing backtraces of running workers in stalled CPU-bound worker pools:
[ 524.265024][ C0] BUG: workqueue lockup - pool cpus=1 node=0 flags=0x0 nice=0 stuck for 506s!
[ 524.265136][ C0] Showing busy workqueues and worker pools:
[ 524.265153][ C0] workqueue mm_percpu_wq: flags=0x8
[ 524.265170][ C0] pwq 6: cpus=1 node=0 flags=0x0 nice=0 active=1 refcnt=2
[ 524.265206][ C0] pending: vmstat_update
[ 524.265371][ C0] Showing backtraces of running workers in stalled CPU-bound worker pools:
[ 554.985000][ C0] BUG: workqueue lockup - pool cpus=1 node=0 flags=0x0 nice=0 stuck for 537s!
[ 554.985069][ C0] Showing busy workqueues and worker pools:
[ 554.985080][ C0] workqueue mm_percpu_wq: flags=0x8
[ 554.985089][ C0] pwq 6: cpus=1 node=0 flags=0x0 nice=0 active=1 refcnt=2
[ 554.985107][ C0] pending: vmstat_update
[ 554.985213][ C0] Showing backtraces of running workers in stalled CPU-bound worker pools:
[ 585.704946][ C0] BUG: workqueue lockup - pool cpus=1 node=0 flags=0x0 nice=0 stuck for 567s!
[ 585.704998][ C0] Showing busy workqueues and worker pools:
[ 585.705006][ C0] workqueue mm_percpu_wq: flags=0x8
[ 585.705013][ C0] pwq 6: cpus=1 node=0 flags=0x0 nice=0 active=1 refcnt=2
[ 585.705026][ C0] pending: vmstat_update
[ 585.705098][ C0] Showing backtraces of running workers in stalled CPU-bound worker pools:
[ 616.424942][ C0] BUG: workqueue lockup - pool cpus=1 node=0 flags=0x0 nice=0 stuck for 598s!
[ 616.424990][ C0] Showing busy workqueues and worker pools:
[ 616.424997][ C0] workqueue mm_percpu_wq: flags=0x8
[ 616.425003][ C0] pwq 6: cpus=1 node=0 flags=0x0 nice=0 active=1 refcnt=2
[ 616.425015][ C0] pending: vmstat_update
[ 616.425082][ C0] Showing backtraces of running workers in stalled CPU-bound worker pools:
[ 647.144950][ C0] BUG: workqueue lockup - pool cpus=1 node=0 flags=0x0 nice=0 stuck for 629s!
[ 647.145035][ C0] Showing busy workqueues and worker pools:
[ 647.145047][ C0] workqueue mm_percpu_wq: flags=0x8
[ 647.145059][ C0] pwq 6: cpus=1 node=0 flags=0x0 nice=0 active=1 refcnt=2
[ 647.145084][ C0] pending: vmstat_update
[ 647.145202][ C0] Showing backtraces of running workers in stalled CPU-bound worker pools:
[ 674.477504][ C1] watchdog: BUG: soft lockup - CPU#1 stuck for 626s! [swapper/0:1]
[ 674.477539][ C1] CPU#1 Utilization every 96s during lockup:
[ 674.477543][ C1] #1: 100% system, 1% softirq, 1% hardirq, 0% idle
[ 674.477549][ C1] #2: 100% system, 1% softirq, 1% hardirq, 0% idle
[ 674.477553][ C1] #3: 100% system, 0% softirq, 1% hardirq, 0% idle
[ 674.477557][ C1] #4: 100% system, 1% softirq, 1% hardirq, 0% idle
[ 674.477561][ C1] #5: 100% system, 1% softirq, 1% hardirq, 0% idle
[ 674.477566][ C1] Modules linked in:
[ 674.477571][ C1] irq event stamp: 852298
[ 674.477574][ C1] hardirqs last enabled at (852297): asm_sysvec_apic_timer_interrupt (arch/x86/include/asm/idtentry.h:702)
[ 674.477592][ C1] hardirqs last disabled at (852298): sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1050)
[ 674.477603][ C1] softirqs last enabled at (852280): handle_softirqs (arch/x86/include/asm/preempt.h:27 kernel/softirq.c:426 kernel/softirq.c:607)
[ 674.477612][ C1] softirqs last disabled at (852275): __irq_exit_rcu (arch/x86/include/asm/jump_label.h:36 kernel/softirq.c:682)
[ 674.477622][ C1] CPU: 1 UID: 0 PID: 1 Comm: swapper/0 Not tainted 6.17.0-rc6-01063-ga3ae9f413a97 #1 VOLUNTARY
[ 674.477629][ C1] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
[ 674.477634][ C1] RIP: 0010:__sanitizer_cov_trace_pc (arch/x86/include/asm/preempt.h:27 kernel/kcov.c:183 kernel/kcov.c:217)
[ 674.477644][ C1] Code: 48 c7 c7 00 a1 59 8a 48 89 de e8 be 1e 42 01 eb 85 cc cc cc cc cc cc cc cc cc cc cc cc 48 8b 04 24 65 48 8b 0c 25 08 30 0a 8d <65> 8b 15 dc c0 97 0b 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75
All code
========
0: 48 c7 c7 00 a1 59 8a mov $0xffffffff8a59a100,%rdi
7: 48 89 de mov %rbx,%rsi
a: e8 be 1e 42 01 call 0x1421ecd
f: eb 85 jmp 0xffffffffffffff96
11: cc int3
12: cc int3
13: cc int3
14: cc int3
15: cc int3
16: cc int3
17: cc int3
18: cc int3
19: cc int3
1a: cc int3
1b: cc int3
1c: cc int3
1d: 48 8b 04 24 mov (%rsp),%rax
21: 65 48 8b 0c 25 08 30 mov %gs:0xffffffff8d0a3008,%rcx
28: 0a 8d
2a:* 65 8b 15 dc c0 97 0b mov %gs:0xb97c0dc(%rip),%edx # 0xb97c10d <-- trapping instruction
31: 81 e2 00 01 ff 00 and $0xff0100,%edx
37: 74 11 je 0x4a
39: 81 fa 00 01 00 00 cmp $0x100,%edx
3f: 75 .byte 0x75
Code starting with the faulting instruction
===========================================
0: 65 8b 15 dc c0 97 0b mov %gs:0xb97c0dc(%rip),%edx # 0xb97c0e3
7: 81 e2 00 01 ff 00 and $0xff0100,%edx
d: 74 11 je 0x20
f: 81 fa 00 01 00 00 cmp $0x100,%edx
15: 75 .byte 0x75
[ 674.477650][ C1] RSP: 0018:ffffc9000001f138 EFLAGS: 00200287
[ 674.477656][ C1] RAX: ffffffff831e1d39 RBX: ffff888160a713c0 RCX: ffff888100871b00
[ 674.477660][ C1] RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8bc06cf0
[ 674.477664][ C1] RBP: 0000000000000032 R08: ffffffff8bc06cf7 R09: 1ffffffff1780d9e
[ 674.477669][ C1] R10: dffffc0000000000 R11: fffffbfff1780d9f R12: dffffc0000000000
[ 674.477674][ C1] R13: 1ffff1102c14e27e R14: 0000000000000000 R15: ffff88817b2bd5a0
[ 674.477678][ C1] FS: 0000000000000000(0000) GS:ffff88842127d000(0000) knlGS:0000000000000000
[ 674.477683][ C1] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 674.477687][ C1] CR2: 00000000f7f5ecd4 CR3: 000000000a0c3000 CR4: 00000000000406f0
[ 674.477695][ C1] Call Trace:
[ 674.477710][ C1] <TASK>
[ 674.477713][ C1] drm_atomic_add_encoder_bridges (drivers/gpu/drm/drm_atomic.c:1319 (discriminator 1025))
[ 674.477734][ C1] drm_atomic_helper_check_modeset (drivers/gpu/drm/drm_atomic_helper.c:818)
[ 674.477767][ C1] drm_atomic_helper_check (drivers/gpu/drm/drm_atomic_helper.c:1112)
[ 674.477775][ C1] ? vgem_fence_release (drivers/gpu/drm/vkms/vkms_drv.c:95)
[ 674.477786][ C1] drm_atomic_check_only (drivers/gpu/drm/drm_atomic.c:1503)
[ 674.477808][ C1] drm_atomic_commit (drivers/gpu/drm/drm_atomic.c:1571)
[ 674.477816][ C1] ? dump_dte_entry (drivers/gpu/drm/drm_print.c:210)
[ 674.477829][ C1] drm_client_modeset_commit_atomic (drivers/gpu/drm/drm_client_modeset.c:?)
[ 674.477862][ C1] drm_client_modeset_commit_locked (drivers/gpu/drm/drm_client_modeset.c:1206)
[ 674.477874][ C1] drm_client_modeset_commit (drivers/gpu/drm/drm_client_modeset.c:1232)
[ 674.477882][ C1] __drm_fb_helper_restore_fbdev_mode_unlocked (drivers/gpu/drm/drm_fb_helper.c:?)
[ 674.477895][ C1] drm_fb_helper_set_par (drivers/gpu/drm/drm_fb_helper.c:?)
[ 674.477904][ C1] ? drm_fb_pixel_format_equal (drivers/gpu/drm/drm_fb_helper.c:1316)
[ 674.477913][ C1] fbcon_init (drivers/video/fbdev/core/fbcon.c:1153)
[ 674.477935][ C1] visual_init (drivers/tty/vt/vt.c:?)
[ 674.477949][ C1] do_bind_con_driver (drivers/tty/vt/vt.c:3916)
[ 674.477964][ C1] do_take_over_console (drivers/tty/vt/vt.c:?)
[ 674.477983][ C1] do_fbcon_takeover (drivers/video/fbdev/core/fbcon.c:589)
[ 674.477993][ C1] fbcon_fb_registered (drivers/video/fbdev/core/fbcon.c:3022)
[ 674.478005][ C1] register_framebuffer (drivers/video/fbdev/core/fbmem.c:512)
[ 674.478022][ C1] __drm_fb_helper_initial_config_and_unlock (drivers/gpu/drm/drm_fb_helper.c:1835)
[ 674.478050][ C1] drm_fbdev_client_hotplug (drivers/gpu/drm/clients/drm_fbdev_client.c:53)
[ 674.478065][ C1] drm_client_register (drivers/gpu/drm/drm_client.c:142)
[ 674.478077][ C1] drm_fbdev_client_setup (drivers/gpu/drm/clients/drm_fbdev_client.c:?)
[ 674.478090][ C1] drm_client_setup (drivers/gpu/drm/clients/drm_client_setup.c:47)
[ 674.478102][ C1] vkms_init (drivers/gpu/drm/vkms/vkms_drv.c:227)
[ 674.478116][ C1] ? vgem_init (drivers/gpu/drm/vkms/vkms_drv.c:213)
[ 674.478121][ C1] do_one_initcall (init/main.c:1269)
[ 674.478137][ C1] ? stack_depot_save_flags (lib/stackdepot.c:722)
[ 674.478153][ C1] ? kasan_save_track (arch/x86/include/asm/current.h:25 (discriminator 3) mm/kasan/common.c:60 (discriminator 3) mm/kasan/common.c:69 (discriminator 3))
[ 674.478161][ C1] ? kasan_save_track (mm/kasan/common.c:48 mm/kasan/common.c:68)
[ 674.478168][ C1] ? __kasan_kmalloc (mm/kasan/common.c:409)
[ 674.478176][ C1] ? __kmalloc_noprof (include/linux/kasan.h:260 mm/slub.c:4376 mm/slub.c:4388)
[ 674.478181][ C1] ? do_initcalls (init/main.c:1341)
[ 674.478188][ C1] ? kernel_init_freeable (init/main.c:1581)
[ 674.478193][ C1] ? kernel_init (init/main.c:1471)
[ 674.478200][ C1] ? ret_from_fork (arch/x86/kernel/process.c:154)
[ 674.478207][ C1] ? ret_from_fork_asm (arch/x86/entry/entry_64.S:258)
[ 674.478225][ C1] ? asm_sysvec_apic_timer_interrupt (arch/x86/include/asm/idtentry.h:702)
[ 674.478241][ C1] ? strlen (lib/string.c:420 (discriminator 769))
[ 674.478250][ C1] ? next_arg (lib/cmdline.c:273)
[ 674.478261][ C1] ? parameq (kernel/params.c:91 (discriminator 2048) kernel/params.c:99 (discriminator 2048))
[ 674.478263][ C1] ? parse_args (kernel/params.c:?)
[ 674.478263][ C1] do_initcall_level (init/main.c:1330 (discriminator 6))
[ 674.478263][ C1] do_initcalls (init/main.c:1344 (discriminator 2))
[ 674.478263][ C1] kernel_init_freeable (init/main.c:1581)
[ 674.478263][ C1] ? rest_init (init/main.c:1461)
[ 674.478263][ C1] kernel_init (init/main.c:1471)
[ 674.478263][ C1] ? rest_init (init/main.c:1461)
[ 674.478263][ C1] ret_from_fork (arch/x86/kernel/process.c:154)
[ 674.478341][ C1] ? rest_init (init/main.c:1461)
[ 674.478341][ C1] ret_from_fork_asm (arch/x86/entry/entry_64.S:258)
[ 674.478341][ C1] </TASK>
[ 674.478341][ C1] Kernel panic - not syncing: softlockup: hung tasks
[ 674.478341][ C1] CPU: 1 UID: 0 PID: 1 Comm: swapper/0 Tainted: G L 6.17.0-rc6-01063-ga3ae9f413a97 #1 VOLUNTARY
[ 674.478341][ C1] Tainted: [L]=SOFTLOCKUP
[ 674.478341][ C1] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
[ 674.478341][ C1] Call Trace:
[ 674.478341][ C1] <IRQ>
[ 674.478341][ C1] vpanic (kernel/panic.c:?)
[ 674.478341][ C1] panic (??:?)
[ 674.478341][ C1] watchdog_timer_fn (kernel/watchdog.c:832)
[ 674.478341][ C1] ? softlockup_count_show (kernel/watchdog.c:733)
[ 674.478341][ C1] __hrtimer_run_queues (kernel/time/hrtimer.c:1761)
[ 674.478341][ C1] hrtimer_interrupt (kernel/time/hrtimer.c:1890)
[ 674.478341][ C1] __sysvec_apic_timer_interrupt (arch/x86/include/asm/jump_label.h:36 arch/x86/include/asm/trace/irq_vectors.h:40 arch/x86/kernel/apic/apic.c:1057)
[ 674.478341][ C1] sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1050 (discriminator 24))
[ 674.478341][ C1] </IRQ>
[ 674.478341][ C1] <TASK>
[ 674.478341][ C1] asm_sysvec_apic_timer_interrupt (arch/x86/include/asm/idtentry.h:702)
[ 674.478341][ C1] RIP: 0010:__sanitizer_cov_trace_pc (arch/x86/include/asm/preempt.h:27 kernel/kcov.c:183 kernel/kcov.c:217)
[ 674.478341][ C1] Code: 48 c7 c7 00 a1 59 8a 48 89 de e8 be 1e 42 01 eb 85 cc cc cc cc cc cc cc cc cc cc cc cc 48 8b 04 24 65 48 8b 0c 25 08 30 0a 8d <65> 8b 15 dc c0 97 0b 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75
All code
========
0: 48 c7 c7 00 a1 59 8a mov $0xffffffff8a59a100,%rdi
7: 48 89 de mov %rbx,%rsi
a: e8 be 1e 42 01 call 0x1421ecd
f: eb 85 jmp 0xffffffffffffff96
11: cc int3
12: cc int3
13: cc int3
14: cc int3
15: cc int3
16: cc int3
17: cc int3
18: cc int3
19: cc int3
1a: cc int3
1b: cc int3
The kernel config and materials to reproduce are available at:
https://download.01.org/0day-ci/archive/20250930/202509301358.38036b85-lkp@intel.com
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
next prev parent reply other threads:[~2025-09-30 6:16 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-09-26 15:59 [PATCH 0/7] drm/bridge: protect encoder bridge chain with a mutex Luca Ceresoli
2025-09-26 15:59 ` [PATCH 1/7] drm/encoder: add mutex to protect the bridge chain Luca Ceresoli
2025-09-29 12:43 ` Maxime Ripard
2025-09-29 14:45 ` Luca Ceresoli
2025-09-26 15:59 ` [PATCH 2/7] drm/encoder: drm_encoder_cleanup: take chain mutex while tearing down Luca Ceresoli
2025-09-29 12:45 ` Maxime Ripard
2025-09-29 14:31 ` Luca Ceresoli
2025-10-03 10:37 ` Luca Ceresoli
2025-09-26 15:59 ` [PATCH 3/7] drm/bridge: lock the encoder bridge chain mutex during insertion Luca Ceresoli
2025-09-29 12:46 ` Maxime Ripard
2025-09-29 14:53 ` Luca Ceresoli
2025-09-26 15:59 ` [PATCH 4/7] drm/bridge: lock the encoder chain in scoped for_each loops Luca Ceresoli
2025-09-30 6:16 ` kernel test robot [this message]
2025-10-02 15:33 ` Luca Ceresoli
2025-09-26 15:59 ` [PATCH 5/7] drm/bridge: prevent encoder chain changes while iterating with list_for_each_entry_from() Luca Ceresoli
2025-09-26 15:59 ` [PATCH 6/7] drm/bridge: prevent encoder chain changes while iterating with list_for_each_entry_reverse() Luca Ceresoli
2025-09-26 15:59 ` [PATCH 7/7] drm/bridge: prevent encoder chain changes while iterating in drm_atomic_bridge_chain_post_disable/pre_enable() Luca Ceresoli
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=202509301358.38036b85-lkp@intel.com \
--to=oliver.sang@intel.com \
--cc=Hui.Pu@gehealthcare.com \
--cc=Laurent.pinchart@ideasonboard.com \
--cc=airlied@gmail.com \
--cc=andrzej.hajda@intel.com \
--cc=dri-devel@lists.freedesktop.org \
--cc=jernej.skrabec@gmail.com \
--cc=jonas@kwiboo.se \
--cc=linux-kernel@vger.kernel.org \
--cc=lkp@intel.com \
--cc=luca.ceresoli@bootlin.com \
--cc=maarten.lankhorst@linux.intel.com \
--cc=mripard@kernel.org \
--cc=neil.armstrong@linaro.org \
--cc=oe-lkp@lists.linux.dev \
--cc=rfoss@kernel.org \
--cc=simona@ffwll.ch \
--cc=thomas.petazzoni@bootlin.com \
--cc=tzimmermann@suse.de \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.