Re: drm-tip: Possible deadlock in DRM FB helpers

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Tue, Jun 11, 2019 at 11:27 AM Thomas Zimmermann <tzimmermann@xxxxxxx> wrote:
>
> Hi,
>
> since a few days, I get a deadlock warning about the DRM FB helpers in
> drm-tip. I was able to trace the problem back to
>
>   d81294afe drm/fb-helper: Remove drm_fb_helper_crtc
>
> It moves around some lock operations, which breaks non-atomic drivers
> (radeon, mgag200, ast). An lspci and dmesg snippet from my test system
> is included below.

>From a quick look the client->modeset_mutex is taken too deep in the
callchain for pan_set. It needs to be moved out, outside of all the
core kms locking, like with fb_helper_dpms. I think that should fix
the issue.
-Daniel

> Best regards
> Thomas
>
>
>  * lspci -v
>
> 01:00.0 VGA compatible controller: Advanced Micro Devices, Inc.
> [AMD/ATI] Oland [Radeon HD 8570 / R7 240/340 OEM] (prog-if 00 [VGA
> controller])
>         Subsystem: Dell Radeon R5 240 OEM
>         Flags: bus master, fast devsel, latency 0, IRQ 32
>         Memory at e0000000 (64-bit, prefetchable) [size=256M]
>         Memory at f7c00000 (64-bit, non-prefetchable) [size=256K]
>         I/O ports at e000 [size=256]
>         Expansion ROM at 000c0000 [disabled] [size=128K]
>         Capabilities: [48] Vendor Specific Information: Len=08 <?>
>         Capabilities: [50] Power Management version 3
>         Capabilities: [58] Express Legacy Endpoint, MSI 00
>         Capabilities: [a0] MSI: Enable+ Count=1/1 Maskable- 64bit+
>         Capabilities: [100] Vendor Specific Information: ID=0001 Rev=1
> Len=010 <?>
>         Capabilities: [150] Advanced Error Reporting
>         Capabilities: [200] Resizable BAR <?>
>         Capabilities: [270] Secondary PCI Express <?>
>         Kernel driver in use: radeon
>         Kernel modules: radeon, amdgpu
>
>  * dmesg
>
>
> [    4.959319] fbcon: radeondrmfb (fb0) is primary device
> [    4.993952] Console: switching to colour frame buffer device 240x67
> [    4.994040]
> [    4.994041] ======================================================
> [    4.994041] WARNING: possible circular locking dependency detected
> [    4.994042] 5.2.0-rc4-1-default+ #39 Tainted: G            E
> [    4.994043] ------------------------------------------------------
> [    4.994043] systemd-udevd/369 is trying to acquire lock:
> [    4.994044] 00000000fb622acb (&client->modeset_mutex){+.+.}, at:
> drm_fb_helper_pan_display+0x103/0x1f0 [drm_kms_helper]
> [    4.994055]
> [    4.994055] but task is already holding lock:
> [    4.994055] 0000000028767ae4 (crtc_ww_class_mutex){+.+.}, at:
> drm_modeset_lock+0x42/0xf0 [drm]
> [    4.994072]
> [    4.994072] which lock already depends on the new lock.
> [    4.994072]
> [    4.994072]
> [    4.994072] the existing dependency chain (in reverse order) is:
> [    4.994073]
> [    4.994073] -> #3 (crtc_ww_class_mutex){+.+.}:
> [    4.994076]        lock_acquire+0x9e/0x170
> [    4.994079]        __ww_mutex_lock.constprop.18+0x97/0xf40
> [    4.994080]        ww_mutex_lock+0x30/0x90
> [    4.994091]        drm_modeset_lock+0x42/0xf0 [drm]
> [    4.994102]        drm_modeset_lock_all_ctx+0x1f/0xe0 [drm]
> [    4.994113]        drm_modeset_lock_all+0x5e/0x1a0 [drm]
> [    4.994163]        intel_modeset_init+0x60b/0xda0 [i915]
> [    4.994196]        i915_driver_load+0xd17/0x1730 [i915]
> [    4.994228]        i915_pci_probe+0x44/0x130 [i915]
> [    4.994231]        local_pci_probe+0x42/0x80
> [    4.994232]        pci_device_probe+0xf1/0x170
> [    4.994234]        really_probe+0xef/0x390
> [    4.994235]        driver_probe_device+0xb4/0x100
> [    4.994237]        device_driver_attach+0x4f/0x60
> [    4.994238]        __driver_attach+0x88/0x140
> [    4.994239]        bus_for_each_dev+0x66/0x90
> [    4.994240]        bus_add_driver+0x134/0x1e0
> [    4.994241]        driver_register+0x6b/0xb0
> [    4.994244]        do_one_initcall+0x5d/0x2b4
> [    4.994246]        do_init_module+0x5a/0x220
> [    4.994248]        load_module+0x17d4/0x1a90
> [    4.994249]        __do_sys_finit_module+0x8f/0xd0
> [    4.994251]        do_syscall_64+0x60/0x1c0
> [    4.994252]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
> [    4.994253]
> [    4.994253] -> #2 (crtc_ww_class_acquire){+.+.}:
> [    4.994255]        lock_acquire+0x9e/0x170
> [    4.994270]        drm_modeset_acquire_init+0xcc/0x100 [drm]
> [    4.994280]        drm_modeset_lock_all+0x44/0x1a0 [drm]
> [    4.994320]        intel_modeset_init+0x60b/0xda0 [i915]
> [    4.994352]        i915_driver_load+0xd17/0x1730 [i915]
> [    4.994385]        i915_pci_probe+0x44/0x130 [i915]
> [    4.994387]        local_pci_probe+0x42/0x80
> [    4.994387]        pci_device_probe+0xf1/0x170
> [    4.994389]        really_probe+0xef/0x390
> [    4.994390]        driver_probe_device+0xb4/0x100
> [    4.994391]        device_driver_attach+0x4f/0x60
> [    4.994392]        __driver_attach+0x88/0x140
> [    4.994393]        bus_for_each_dev+0x66/0x90
> [    4.994394]        bus_add_driver+0x134/0x1e0
> [    4.994395]        driver_register+0x6b/0xb0
> [    4.994396]        do_one_initcall+0x5d/0x2b4
> [    4.994398]        do_init_module+0x5a/0x220
> [    4.994399]        load_module+0x17d4/0x1a90
> [    4.994400]        __do_sys_finit_module+0x8f/0xd0
> [    4.994402]        do_syscall_64+0x60/0x1c0
> [    4.994403]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
> [    4.994403]
> [    4.994403] -> #1 (&dev->mode_config.mutex){+.+.}:
> [    4.994405]        lock_acquire+0x9e/0x170
> [    4.994408]        __mutex_lock+0x62/0x8c0
> [    4.994413]        drm_setup_crtcs+0x17c/0xc50 [drm_kms_helper]
> [    4.994418]
> __drm_fb_helper_initial_config_and_unlock+0x34/0x530 [drm_kms_helper]
> [    4.994450]        radeon_fbdev_init+0x110/0x130 [radeon]
> [    4.994477]        radeon_modeset_init.cold.12+0x198/0x4ec [radeon]
> [    4.994500]        radeon_driver_load_kms+0xc1/0x250 [radeon]
> [    4.994508]        drm_dev_register+0x10f/0x150 [drm]
> [    4.994517]        drm_get_pci_dev+0x95/0x190 [drm]
> [    4.994519]        local_pci_probe+0x42/0x80
> [    4.994520]        pci_device_probe+0xf1/0x170
> [    4.994521]        really_probe+0xef/0x390
> [    4.994522]        driver_probe_device+0xb4/0x100
> [    4.994523]        device_driver_attach+0x4f/0x60
> [    4.994524]        __driver_attach+0x88/0x140
> [    4.994525]        bus_for_each_dev+0x66/0x90
> [    4.994526]        bus_add_driver+0x134/0x1e0
> [    4.994527]        driver_register+0x6b/0xb0
> [    4.994528]        do_one_initcall+0x5d/0x2b4
> [    4.994530]        do_init_module+0x5a/0x220
> [    4.994531]        load_module+0x17d4/0x1a90
> [    4.994532]        __do_sys_finit_module+0x8f/0xd0
> [    4.994533]        do_syscall_64+0x60/0x1c0
> [    4.994535]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
> [    4.994535]
> [    4.994535] -> #0 (&client->modeset_mutex){+.+.}:
> [    4.994537]        __lock_acquire+0xa85/0xe90
> [    4.994538]        lock_acquire+0x9e/0x170
> [    4.994540]        __mutex_lock+0x62/0x8c0
> [    4.994545]        drm_fb_helper_pan_display+0x103/0x1f0 [drm_kms_helper]
> [    4.994547]        fb_pan_display+0x92/0x120
> [    4.994549]        bit_update_start+0x1a/0x40
> [    4.994550]        fbcon_switch+0x392/0x580
> [    4.994552]        redraw_screen+0x12c/0x220
> [    4.994553]        do_bind_con_driver.cold.30+0xe1/0x10d
> [    4.994554]        do_take_over_console+0x113/0x190
> [    4.994555]        do_fbcon_takeover+0x58/0xb0
> [    4.994557]        notifier_call_chain+0x47/0x70
> [    4.994558]        blocking_notifier_call_chain+0x44/0x60
> [    4.994559]        register_framebuffer+0x231/0x310
> [    4.994564]
> __drm_fb_helper_initial_config_and_unlock+0x2fd/0x530 [drm_kms_helper]
> [    4.994590]        radeon_fbdev_init+0x110/0x130 [radeon]
> [    4.994615]        radeon_modeset_init.cold.12+0x198/0x4ec [radeon]
> [    4.994638]        radeon_driver_load_kms+0xc1/0x250 [radeon]
> [    4.994647]        drm_dev_register+0x10f/0x150 [drm]
> [    4.994655]        drm_get_pci_dev+0x95/0x190 [drm]
> [    4.994657]        local_pci_probe+0x42/0x80
> [    4.994658]        pci_device_probe+0xf1/0x170
> [    4.994659]        really_probe+0xef/0x390
> [    4.994660]        driver_probe_device+0xb4/0x100
> [    4.994661]        device_driver_attach+0x4f/0x60
> [    4.994662]        __driver_attach+0x88/0x140
> [    4.994663]        bus_for_each_dev+0x66/0x90
> [    4.994664]        bus_add_driver+0x134/0x1e0
> [    4.994665]        driver_register+0x6b/0xb0
> [    4.994666]        do_one_initcall+0x5d/0x2b4
> [    4.994668]        do_init_module+0x5a/0x220
> [    4.994669]        load_module+0x17d4/0x1a90
> [    4.994670]        __do_sys_finit_module+0x8f/0xd0
> [    4.994671]        do_syscall_64+0x60/0x1c0
> [    4.994673]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
> [    4.994673]
> [    4.994673] other info that might help us debug this:
> [    4.994673]
> [    4.994673] Chain exists of:
> [    4.994673]   &client->modeset_mutex --> crtc_ww_class_acquire -->
> crtc_ww_class_mutex
> [    4.994673]
> [    4.994675]  Possible unsafe locking scenario:
> [    4.994675]
> [    4.994675]        CPU0                    CPU1
> [    4.994676]        ----                    ----
> [    4.994676]   lock(crtc_ww_class_mutex);
> [    4.994677]                                lock(crtc_ww_class_acquire);
> [    4.994677]                                lock(crtc_ww_class_mutex);
> [    4.994678]   lock(&client->modeset_mutex);
> [    4.994679]
> [    4.994679]  *** DEADLOCK ***
> [    4.994679]
> [    4.994679] 11 locks held by systemd-udevd/369:
> [    4.994680]  #0: 000000002a864971 (&dev->mutex){....}, at:
> device_driver_attach+0x1d/0x60
> [    4.994682]  #1: 0000000079b4fff6 (drm_global_mutex){+.+.}, at:
> drm_dev_register+0x27/0x150 [drm]
> [    4.994691]  #2: 00000000ae4b249f (registration_lock){+.+.}, at:
> register_framebuffer+0x29/0x310
> [    4.994694]  #3: 00000000baa4b33b (console_lock){+.+.}, at:
> register_framebuffer+0x2ad/0x310
> [    4.994696]  #4: 0000000052aa04e9 (&fb_info->lock){+.+.}, at:
> lock_fb_info+0x18/0x40
> [    4.994698]  #5: 00000000ee198c3a ((fb_notifier_list).rwsem){++++},
> at: blocking_notifier_call_chain+0x2a/0x60
> [    4.994701]  #6: 00000000283d5679 (&helper->lock){+.+.}, at:
> drm_fb_helper_pan_display+0x48/0x1f0 [drm_kms_helper]
> [    4.994707]  #7: 000000007cd70e4c (&dev->master_mutex){+.+.}, at:
> drm_master_internal_acquire+0x1b/0x40 [drm]
> [    4.994715]  #8: 0000000069bce718 (&dev->mode_config.mutex){+.+.},
> at: drm_modeset_lock_all+0x3a/0x1a0 [drm]
> [    4.994726]  #9: 00000000aa42b785 (crtc_ww_class_acquire){+.+.}, at:
> drm_modeset_lock_all+0x44/0x1a0 [drm]
> [    4.994738]  #10: 0000000028767ae4 (crtc_ww_class_mutex){+.+.}, at:
> drm_modeset_lock+0x42/0xf0 [drm]
> [    4.994750]
> [    4.994750] stack backtrace:
> [    4.994752] CPU: 7 PID: 369 Comm: systemd-udevd Tainted: G
>  E     5.2.0-rc4-1-default+ #39
> [    4.994752] Hardware name: Dell Inc. OptiPlex 9020/0N4YC8, BIOS A24
> 10/24/2018
> [    4.994753] Call Trace:
> [    4.994756]  dump_stack+0x85/0xc0
> [    4.994758]  print_circular_bug.cold.62+0x15c/0x195
> [    4.994760]  check_prevs_add+0x7ff/0xf40
> [    4.994763]  ? find_held_lock+0x34/0xa0
> [    4.994774]  ? drm_modeset_lock+0x42/0xf0 [drm]
> [    4.994775]  __lock_acquire+0xa85/0xe90
> [    4.994777]  lock_acquire+0x9e/0x170
> [    4.994782]  ? drm_fb_helper_pan_display+0x103/0x1f0 [drm_kms_helper]
> [    4.994788]  ? drm_fb_helper_pan_display+0x103/0x1f0 [drm_kms_helper]
> [    4.994790]  __mutex_lock+0x62/0x8c0
> [    4.994795]  ? drm_fb_helper_pan_display+0x103/0x1f0 [drm_kms_helper]
> [    4.994796]  ? ww_mutex_lock+0x30/0x90
> [    4.994798]  ? _cond_resched+0x15/0x30
> [    4.994799]  ? ww_mutex_lock+0x30/0x90
> [    4.994810]  ? drm_modeset_lock+0x42/0xf0 [drm]
> [    4.994816]  ? drm_fb_helper_pan_display+0x103/0x1f0 [drm_kms_helper]
> [    4.994821]  drm_fb_helper_pan_display+0x103/0x1f0 [drm_kms_helper]
> [    4.994823]  fb_pan_display+0x92/0x120
> [    4.994825]  bit_update_start+0x1a/0x40
> [    4.994826]  fbcon_switch+0x392/0x580
> [    4.994829]  redraw_screen+0x12c/0x220
> [    4.994831]  do_bind_con_driver.cold.30+0xe1/0x10d
> [    4.994833]  do_take_over_console+0x113/0x190
> [    4.994835]  do_fbcon_takeover+0x58/0xb0
> [    4.994836]  notifier_call_chain+0x47/0x70
> [    4.994838]  blocking_notifier_call_chain+0x44/0x60
> [    4.994839]  ? lock_fb_info+0x18/0x40
> [    4.994841]  register_framebuffer+0x231/0x310
> [    4.994847]  __drm_fb_helper_initial_config_and_unlock+0x2fd/0x530
> [drm_kms_helper]
> [    4.994873]  radeon_fbdev_init+0x110/0x130 [radeon]
> [    4.994899]  radeon_modeset_init.cold.12+0x198/0x4ec [radeon]
> [    4.994923]  radeon_driver_load_kms+0xc1/0x250 [radeon]
> [    4.994932]  drm_dev_register+0x10f/0x150 [drm]
> [    4.994942]  drm_get_pci_dev+0x95/0x190 [drm]
> [    4.994944]  local_pci_probe+0x42/0x80
> [    4.994946]  pci_device_probe+0xf1/0x170
> [    4.994948]  really_probe+0xef/0x390
> [    4.994949]  driver_probe_device+0xb4/0x100
> [    4.994951]  device_driver_attach+0x4f/0x60
> [    4.994952]  __driver_attach+0x88/0x140
> [    4.994953]  ? device_driver_attach+0x60/0x60
> [    4.994954]  bus_for_each_dev+0x66/0x90
> [    4.994956]  bus_add_driver+0x134/0x1e0
> [    4.994957]  ? 0xffffffffc0870000
> [    4.994959]  driver_register+0x6b/0xb0
> [    4.994960]  ? 0xffffffffc0870000
> [    4.994961]  do_one_initcall+0x5d/0x2b4
> [    4.994964]  do_init_module+0x5a/0x220
> [    4.994966]  load_module+0x17d4/0x1a90
> [    4.994970]  ? __do_sys_finit_module+0x8f/0xd0
> [    4.994971]  __do_sys_finit_module+0x8f/0xd0
> [    4.994974]  do_syscall_64+0x60/0x1c0
> [    4.994976]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
> [    4.994977] RIP: 0033:0x7f10b1261449
> [    4.994978] 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 1f 4a 0c 00 f7 d8 64 89 01 48
> [    4.994979] RSP: 002b:00007ffd6e07fd78 EFLAGS: 00000246 ORIG_RAX:
> 0000000000000139
> [    4.994980] RAX: ffffffffffffffda RBX: 00005627690c73d0 RCX:
> 00007f10b1261449
> [    4.994981] RDX: 0000000000000000 RSI: 00007f10b13c289d RDI:
> 000000000000000e
> [    4.994982] RBP: 0000000000020000 R08: 0000000000000000 R09:
> 00005627690ce930
> [    4.994982] R10: 000000000000000e R11: 0000000000000246 R12:
> 00007f10b13c289d
> [    4.994983] R13: 0000000000000000 R14: 00005627690feba0 R15:
> 00005627690c73d0
>
>
>
>
> --
> Thomas Zimmermann
> Graphics Driver Developer
> SUSE Linux GmbH, Maxfeldstrasse 5, 90409 Nuernberg, Germany
> GF: Felix Imendörffer, Mary Higgins, Sri Rasiah
> HRB 21284 (AG Nürnberg)
>


-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch
_______________________________________________
dri-devel mailing list
dri-devel@xxxxxxxxxxxxxxxxxxxxx
https://lists.freedesktop.org/mailman/listinfo/dri-devel




[Index of Archives]     [Linux DRI Users]     [Linux Intel Graphics]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]     [XFree86]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Linux Kernel]     [Linux SCSI]     [XFree86]
  Powered by Linux