From 886c6b8692ba5f71b578097524b3b082e2e02119 Mon Sep 17 00:00:00 2001 From: Manasi Navare Date: Thu, 26 Oct 2017 14:52:00 -0700 Subject: [PATCH] drm/i915: Cancel the modeset retry work during modeset cleanup During modeset cleanup on driver unload we may have a pending hotplug work. This needs to be canceled early during the teardown so that it does not fire after we have freed the connector. We do this after drm_kms_helper_poll_fini(dev) since this might trigger modeset retry work due to link retrain and before intel_fbdev_fini() since this work requires the lock from fbdev. If this is not done we may see something like: DEBUG_LOCKS_WARN_ON(mutex_is_locked(lock)) ------------[ cut here ]------------ WARNING: CPU: 4 PID: 5010 at kernel/locking/mutex-debug.c:103 mutex_destroy+0x4e/0x60 Modules linked in: i915(-) snd_hda_codec_hdmi snd_hda_codec_realtek snd_hda_codec_generic snd_hda_codec snd_hwdep snd_hda_core snd_pcm vgem ax88179_178 +a usbnet mii x86_pkg_temp_thermal intel_powerclamp coretemp crct10dif_pclmul crc32_pclmul ghash_clmulni_intel e1000e ptp pps_core prime_numbers i2c_hid +[last unloaded: snd_hda_intel] CPU: 4 PID: 5010 Comm: drv_module_relo Tainted: G U 4.14.0-rc3-CI-CI_DRM_3186+ #1 Hardware name: Intel Corporation CoffeeLake Client Platform/CoffeeLake S UDIMM RVP, BIOS CNLSFWX1.R00.X104.A03.1709140524 09/14/2017 task: ffff8803c827aa40 task.stack: ffffc90000520000 RIP: 0010:mutex_destroy+0x4e/0x60 RSP: 0018:ffffc90000523d58 EFLAGS: 00010292 RAX: 000000000000002a RBX: ffff88044fbef648 RCX: 0000000000000000 RDX: 0000000080000001 RSI: 0000000000000001 RDI: ffffffff810f0cf0 RBP: ffffc90000523d60 R08: 0000000000000001 R09: 0000000000000001 R10: 000000000f21cb81 R11: 0000000000000000 R12: ffff88044f71efc8 R13: ffffffffa02b3d20 R14: ffffffffa02b3d90 R15: ffff880459b29308 FS: 00007f5df4d6e8c0(0000) GS:ffff88045d300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055ec51f00a18 CR3: 0000000451782006 CR4: 00000000003606e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: drm_fb_helper_fini+0xd9/0x130 intel_fbdev_destroy+0x12/0x60 [i915] intel_fbdev_fini+0x28/0x30 [i915] intel_modeset_cleanup+0x45/0xa0 [i915] i915_driver_unload+0x92/0x180 [i915] i915_pci_remove+0x19/0x30 [i915] i915_driver_unload+0x92/0x180 [i915] i915_pci_remove+0x19/0x30 [i915] pci_device_remove+0x39/0xb0 device_release_driver_internal+0x15d/0x220 driver_detach+0x40/0x80 bus_remove_driver+0x58/0xd0 driver_unregister+0x2c/0x40 pci_unregister_driver+0x36/0xb0 i915_exit+0x1a/0x8b [i915] SyS_delete_module+0x18c/0x1e0 entry_SYSCALL_64_fastpath+0x1c/0xb1 RIP: 0033:0x7f5df3286287 RSP: 002b:00007fff8e107cc8 EFLAGS: 00000246 ORIG_RAX: 00000000000000b0 RAX: ffffffffffffffda RBX: ffffffff81493a03 RCX: 00007f5df3286287 RDX: 0000000000000001 RSI: 0000000000000800 RDI: 0000564c7be02e48 RBP: ffffc90000523f88 R08: 0000000000000000 R09: 0000000000000080 R10: 00007f5df4d6e8c0 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fff8e107eb0 R14: 0000000000000000 R15: 0000000000000000 Or a GPF like: general protection fault: 0000 [#1] PREEMPT SMP Modules linked in: i915(-) snd_hda_codec_hdmi snd_hda_codec_realtek snd_hda_codec_generic snd_hda_codec snd_hwdep snd_hda_core snd_pcm vgem ax88179_178 +a usbnet mii x86_pkg_temp_thermal intel_powerclamp coretemp crct10dif_pclmul crc32_pclmul ghash_clmulni_intel e1000e ptp pps_core prime_numbers i2c_hid +[last unloaded: snd_hda_intel] CPU: 0 PID: 82 Comm: kworker/0:1 Tainted: G U W 4.14.0-rc3-CI-CI_DRM_3186+ #1 Hardware name: Intel Corporation CoffeeLake Client Platform/CoffeeLake S UDIMM RVP, BIOS CNLSFWX1.R00.X104.A03.1709140524 09/14/2017 Workqueue: events intel_dp_modeset_retry_work_fn [i915] task: ffff88045a5caa40 task.stack: ffffc90000378000 RIP: 0010:drm_setup_crtcs+0x143/0xbf0 RSP: 0018:ffffc9000037bd20 EFLAGS: 00010202 RAX: 6b6b6b6b6b6b6b6b RBX: 0000000000000002 RCX: 0000000000000001 RDX: 0000000000000001 RSI: 0000000000000780 RDI: 00000000ffffffff RBP: ffffc9000037bdb8 R08: 0000000000000001 R09: 0000000000000001 R10: 0000000000000780 R11: 0000000000000000 R12: 0000000000000002 R13: ffff88044fbef4e8 R14: 0000000000000780 R15: 0000000000000438 FS: 0000000000000000(0000) GS:ffff88045d200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055ec51ee5168 CR3: 000000044c89d003 CR4: 00000000003606f0 Call Trace: drm_fb_helper_hotplug_event.part.18+0x7e/0xc0 drm_fb_helper_hotplug_event+0x1a/0x20 intel_fbdev_output_poll_changed+0x1a/0x20 [i915] drm_kms_helper_hotplug_event+0x27/0x30 intel_dp_modeset_retry_work_fn+0x77/0x80 [i915] process_one_work+0x233/0x660 worker_thread+0x206/0x3b0 kthread+0x152/0x190 ? process_one_work+0x660/0x660 ? kthread_create_on_node+0x40/0x40 ret_from_fork+0x27/0x40 Code: 06 00 00 45 8b 45 20 31 db 45 31 e4 45 85 c0 0f 8e 91 06 00 00 44 8b 75 94 44 8b 7d 90 49 8b 45 28 49 63 d4 44 89 f6 41 83 c4 01 <48> 8b 04 d0 44 +89 fa 48 8b 38 48 8b 87 a8 01 00 00 ff 50 20 01 RIP: drm_setup_crtcs+0x143/0xbf0 RSP: ffffc9000037bd20 ---[ end trace 08901ff1a77d30c7 ]--- v2: * Rename it to intel_hpd_poll_fini() and call drm_kms_helper_fini() inside it as the first step before cancel work (Chris Wilson) * Add GPF trace in commit message and make the function static (Maarten Lankhorst) Suggested-by: Maarten Lankhorst Suggested-by: Chris Wilson Fixes: 9301397a63b3 ("drm/i915: Implement Link Rate fallback on Link training failure") Cc: Chris Wilson Cc: Tony Cheng Cc: Harry Wentland Cc: Jani Nikula Cc: Daniel Vetter Cc: Ville Syrjala Cc: Manasi Navare Cc: Maarten Lankhorst Signed-off-by: Manasi Navare Link: https://patchwork.freedesktop.org/patch/msgid/1509054720-25325-1-git-send-email-manasi.d.navare@intel.com Reviewed-by: Chris Wilson Signed-off-by: Chris Wilson --- drivers/gpu/drm/i915/intel_display.c | 19 ++++++++++++++++++- 1 file changed, 18 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index 0e493a1fedab..a369b35d044d 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -15200,6 +15200,23 @@ void intel_connector_unregister(struct drm_connector *connector) intel_panel_destroy_backlight(connector); } +static void intel_hpd_poll_fini(struct drm_device *dev) +{ + struct intel_connector *connector; + struct drm_connector_list_iter conn_iter; + + /* First disable polling... */ + drm_kms_helper_poll_fini(dev); + + /* Then kill the work that may have been queued by hpd. */ + drm_connector_list_iter_begin(dev, &conn_iter); + for_each_intel_connector_iter(connector, &conn_iter) { + if (connector->modeset_retry_work.func) + cancel_work_sync(&connector->modeset_retry_work); + } + drm_connector_list_iter_end(&conn_iter); +} + void intel_modeset_cleanup(struct drm_device *dev) { struct drm_i915_private *dev_priv = to_i915(dev); @@ -15220,7 +15237,7 @@ void intel_modeset_cleanup(struct drm_device *dev) * Due to the hpd irq storm handling the hotplug work can re-arm the * poll handlers. Hence disable polling after hpd handling is shut down. */ - drm_kms_helper_poll_fini(dev); + intel_hpd_poll_fini(dev); /* poll work can call into fbdev, hence clean that up afterwards */ intel_fbdev_fini(dev_priv); -- 2.30.2