From mboxrd@z Thu Jan 1 00:00:00 1970 From: a.hajda@samsung.com (Andrzej Hajda) Date: Tue, 18 Nov 2014 12:04:20 +0100 Subject: [BUG] blocked task after exynos_drm_init In-Reply-To: <546B2508.8070409@samsung.com> References: <1415264811.27478.4.camel@AMDC1943> <546B228E.6030500@samsung.com> <546B2508.8070409@samsung.com> Message-ID: <546B27B4.4040808@samsung.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 11/18/2014 11:52 AM, Inki Dae wrote: > On 2014? 11? 18? 19:42, Andrzej Hajda wrote: >> On 11/06/2014 10:06 AM, Krzysztof Kozlowski wrote: >>> Hi, >>> >>> On last next (next-20141104, next-20141105) booting locks after >>> initializing Exynos DRM (Trats2 board): >>> >>> [ 2.028283] [drm] Initialized drm 1.1.0 20060810 >>> [ 240.505795] INFO: task swapper/0:1 blocked for more than 120 seconds. >>> [ 240.510825] Not tainted 3.18.0-rc3-next-20141105 #794 >>> [ 240.516418] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. >>> [ 240.524173] swapper/0 D c052534c 0 1 0 0x00000000 >>> [ 240.530527] [] (__schedule) from [] (schedule_preempt_disabled+0x14/0x20) >>> [ 240.539030] [] (schedule_preempt_disabled) from [] (mutex_lock_nested+0x1c4/0x464) >>> [ 240.548320] [] (mutex_lock_nested) from [] (__driver_attach+0x48/0x98) >>> [ 240.556562] [] (__driver_attach) from [] (bus_for_each_dev+0x54/0x88) >>> [ 240.564717] [] (bus_for_each_dev) from [] (bus_add_driver+0xe4/0x200) >>> [ 240.572876] [] (bus_add_driver) from [] (driver_register+0x78/0xf4) >>> [ 240.580864] [] (driver_register) from [] (exynos_drm_platform_probe+0x34/0x234) >>> [ 240.589890] [] (exynos_drm_platform_probe) from [] (platform_drv_probe+0x48/0xa4) >>> [ 240.599090] [] (platform_drv_probe) from [] (driver_probe_device+0x13c/0x37c) >>> [ 240.607940] [] (driver_probe_device) from [] (__driver_attach+0x94/0x98) >>> [ 240.616360] [] (__driver_attach) from [] (bus_for_each_dev+0x54/0x88) >>> [ 240.624517] [] (bus_for_each_dev) from [] (bus_add_driver+0xe4/0x200) >>> [ 240.632679] [] (bus_add_driver) from [] (driver_register+0x78/0xf4) >>> [ 240.640667] [] (driver_register) from [] (exynos_drm_init+0x70/0xa0) >>> [ 240.648739] [] (exynos_drm_init) from [] (do_one_initcall+0xac/0x1f0) >>> [ 240.656914] [] (do_one_initcall) from [] (kernel_init_freeable+0x10c/0x1d8) >>> [ 240.665591] [] (kernel_init_freeable) from [] (kernel_init+0x8/0xec) >>> [ 240.673661] [] (kernel_init) from [] (ret_from_fork+0x14/0x2c) >>> [ 240.681196] 3 locks held by swapper/0/1: >>> [ 240.685091] #0: (&dev->mutex){......}, at: [] __driver_attach+0x48/0x98 >>> [ 240.692732] #1: (&dev->mutex){......}, at: [] __driver_attach+0x58/0x98 >>> [ 240.700367] #2: (&dev->mutex){......}, at: [] __driver_attach+0x48/0x98 >> >> >> This is caused by patch moving platform devices to >> /sys/devices/platform[1]. Since this patch registering platform >> drivers/devices in probe of platform device causes deadlocks. I guess >> now all driver registration should be moved to exynos_drm_init and it >> seems better location for it IMHO. > > Thanks. It might be a chance that we could separate sub drivers of > Exynos drm into independent modules so that they can be called > independently because if we move them to exynos_drm_init then the > deferred probe wouldn't work correctly. For full separation of sub-drivers component matching code should be fixed first. Now it usually works because components are probed before exynos_drm_match_add and this is because components are probed during sub-driver registrations. Regards Andrzej > > Thanks, > Inki Dae > >> >> Regards >> Andrzej >> >> [1]: http://www.spinics.net/lists/devicetree/msg56101.html >> >> >> >>> >>> Full dmesg and config attached. >>> >>> Best regards, >>> Krzysztof >>> >>> >>> >>> _______________________________________________ >>> dri-devel mailing list >>> dri-devel at lists.freedesktop.org >>> http://lists.freedesktop.org/mailman/listinfo/dri-devel >>> >> >> >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in >> the body of a message to majordomo at vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html >> > > _______________________________________________ > dri-devel mailing list > dri-devel at lists.freedesktop.org > http://lists.freedesktop.org/mailman/listinfo/dri-devel >