From: Rob Clark <robdcl...@chromium.org> Fix another lockdep splat by pushing the GMU lock further down in the pm_resume path, so that we aren't holding it while preparing/enabling clks. Fixes:
====================================================== WARNING: possible circular locking dependency detected ------------------------------------------------------ 6.4.3-debug+ #14 Not tainted ffffffe487cefb98 (prepare_lock){+.+.}-{3:3}, at: clk_prepare_lock+0x70/0x98 ring0/408 is trying to acquire lock: already holding lock: ffffff809600c6c0 (&a6xx_gpu->gmu.lock){+.+.}-{3:3}, at: a6xx_gmu_pm_resume+0x40/0x170 [msm] which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #4 (&a6xx_gpu->gmu.lock){+.+.}-{3:3}: mutex_lock_nested+0x2c/0x38 __mutex_lock+0xc8/0x388 msm_devfreq_target+0x170/0x18c [msm] a6xx_gpu_set_freq+0x38/0x64 [msm] devfreq_update_target+0xb4/0xf0 devfreq_set_target+0x90/0x1e4 devfreq_monitor+0x3c/0x10c update_devfreq+0x1c/0x28 worker_thread+0x1f0/0x260 process_one_work+0x288/0x3d8 ret_from_fork+0x10/0x20 kthread+0xf0/0x100 -> #3 (&df->lock){+.+.}-{3:3}: mutex_lock_nested+0x2c/0x38 __mutex_lock+0xc8/0x388 devfreq_simple_ondemand_func+0x5c/0x128 msm_devfreq_get_dev_status+0x4c/0x104 [msm] update_devfreq+0x1c/0x28 devfreq_update_target+0x68/0xf0 process_one_work+0x288/0x3d8 devfreq_monitor+0x3c/0x10c kthread+0xf0/0x100 worker_thread+0x1f0/0x260 ret_from_fork+0x10/0x20 devfreq_add_device+0x1b4/0x564 -> #2 (&devfreq->lock){+.+.}-{3:3}: msm_devfreq_init+0xa8/0x16c [msm] devm_devfreq_add_device+0x6c/0xb8 adreno_gpu_init+0x248/0x2b0 [msm] msm_gpu_init+0x368/0x54c [msm] adreno_bind+0x264/0x2bc [msm] a6xx_gpu_init+0x2d0/0x384 [msm] msm_drm_bind+0x2d0/0x5f4 [msm] component_bind_all+0x124/0x1f4 __component_add+0xd4/0x128 try_to_bring_up_aggregate_device+0x88/0x1a4 dp_display_probe+0x37c/0x3c0 [msm] component_add+0x1c/0x28 really_probe+0x148/0x280 platform_probe+0x70/0xc0 driver_probe_device+0x44/0x100 __driver_probe_device+0xfc/0x114 bus_for_each_drv+0xb0/0xd8 __device_attach_driver+0x64/0xdc device_initial_probe+0x1c/0x28 __device_attach+0xe4/0x140 deferred_probe_work_func+0xb0/0xc8 bus_probe_device+0x44/0xb0 worker_thread+0x1f0/0x260 process_one_work+0x288/0x3d8 ret_from_fork+0x10/0x20 kthread+0xf0/0x100 -> #1 (fs_reclaim){+.+.}-{0:0}: fs_reclaim_acquire+0x50/0x9c __fs_reclaim_acquire+0x3c/0x48 __kmem_cache_alloc_node+0x60/0x18c slab_pre_alloc_hook.constprop.0+0x40/0x250 clk_rcg2_dfs_determine_rate+0x60/0x214 kmalloc_trace+0x44/0x88 clk_core_round_rate_nolock+0x84/0x118 clk_core_determine_round_nolock+0xb8/0xf0 clk_round_rate+0x6c/0xd0 clk_core_round_rate_nolock+0xd8/0x118 geni_se_clk_freq_match+0x44/0xe4 geni_se_clk_tbl_get+0x78/0xc0 geni_spi_set_clock_and_bw+0x54/0x104 get_spi_clk_cfg+0x50/0xf4 __spi_pump_transfer_message+0x200/0x4d8 spi_geni_prepare_message+0x130/0x174 spi_sync_locked+0x18/0x24 __spi_sync+0x13c/0x23c cros_ec_xfer_high_pri_work+0x28/0x3c do_cros_ec_pkt_xfer_spi+0x124/0x3f0 kthread+0xf0/0x100 kthread_worker_fn+0x14c/0x27c ret_from_fork+0x10/0x20 __lock_acquire+0xdf8/0x109c -> #0 (prepare_lock){+.+.}-{3:3}: __mutex_lock+0xc8/0x388 lock_acquire+0x234/0x284 clk_prepare_lock+0x70/0x98 mutex_lock_nested+0x2c/0x38 clk_bulk_prepare+0x50/0x9c clk_prepare+0x24/0x50 a6xx_gmu_pm_resume+0x48/0x170 [msm] a6xx_gmu_resume+0x94/0x7d8 [msm] pm_generic_runtime_resume+0x30/0x44 adreno_runtime_resume+0x2c/0x38 [msm] rpm_callback+0x78/0x7c __rpm_callback+0x4c/0x134 __pm_runtime_resume+0x78/0xbc rpm_resume+0x3a4/0x46c msm_gpu_submit+0x4c/0x12c [msm] pm_runtime_get_sync.isra.0+0x14/0x20 [msm] drm_sched_main+0x264/0x354 [gpu_sched] msm_job_run+0x88/0x128 [msm] ret_from_fork+0x10/0x20 kthread+0xf0/0x100 other info that might help us debug this: Chain exists of: prepare_lock --> &df->lock --> &a6xx_gpu->gmu.lock Possible unsafe locking scenario: ---- ---- CPU0 CPU1 lock(&df->lock); lock(&a6xx_gpu->gmu.lock); lock(prepare_lock); lock(&a6xx_gpu->gmu.lock); *** DEADLOCK *** 3 locks held by ring0/408: #1: ffffff809600c170 (&gpu->lock){+.+.}-{3:3}, at: msm_job_run+0x7c/0x128 [msm] #0: ffffffe487d5ae50 (dma_fence_map){++++}-{0:0}, at: drm_sched_main+0x54/0x354 [gpu_sched] #2: ffffff809600c6c0 (&a6xx_gpu->gmu.lock){+.+.}-{3:3}, at: a6xx_gmu_pm_resume+0x40/0x170 [msm] CPU: 1 PID: 408 Comm: ring0 Not tainted 6.4.3-debug+ #14 stack backtrace: Call trace: Hardware name: Google Villager (rev1+) with LTE (DT) show_stack+0x20/0x30 dump_backtrace+0xb4/0xf0 dump_stack+0x18/0x24 dump_stack_lvl+0x60/0x84 check_noncircular+0x78/0xac print_circular_bug+0x1cc/0x234 lock_acquire+0x234/0x284 __lock_acquire+0xdf8/0x109c mutex_lock_nested+0x2c/0x38 __mutex_lock+0xc8/0x388 clk_prepare+0x24/0x50 clk_prepare_lock+0x70/0x98 a6xx_gmu_resume+0x94/0x7d8 [msm] clk_bulk_prepare+0x50/0x9c adreno_runtime_resume+0x2c/0x38 [msm] a6xx_gmu_pm_resume+0x48/0x170 [msm] __rpm_callback+0x4c/0x134 pm_generic_runtime_resume+0x30/0x44 rpm_resume+0x3a4/0x46c rpm_callback+0x78/0x7c pm_runtime_get_sync.isra.0+0x14/0x20 [msm] __pm_runtime_resume+0x78/0xbc msm_job_run+0x88/0x128 [msm] msm_gpu_submit+0x4c/0x12c [msm] drm_sched_main+0x264/0x354 [gpu_sched] kthread+0xf0/0x100 ret_from_fork+0x10/0x20 Signed-off-by: Rob Clark <robdcl...@chromium.org> --- drivers/gpu/drm/msm/adreno/a6xx_gmu.c | 4 ++++ drivers/gpu/drm/msm/adreno/a6xx_gpu.c | 2 -- 2 files changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/msm/adreno/a6xx_gmu.c b/drivers/gpu/drm/msm/adreno/a6xx_gmu.c index 3e0033666a2a..5eb0e812f168 100644 --- a/drivers/gpu/drm/msm/adreno/a6xx_gmu.c +++ b/drivers/gpu/drm/msm/adreno/a6xx_gmu.c @@ -965,6 +965,8 @@ int a6xx_gmu_resume(struct a6xx_gpu *a6xx_gpu) /* Set the bus quota to a reasonable value for boot */ a6xx_gmu_set_initial_bw(gpu, gmu); + mutex_lock(&gmu->lock); + /* Enable the GMU interrupt */ gmu_write(gmu, REG_A6XX_GMU_AO_HOST_INTERRUPT_CLR, ~0); gmu_write(gmu, REG_A6XX_GMU_AO_HOST_INTERRUPT_MASK, ~A6XX_GMU_IRQ_MASK); @@ -1009,6 +1011,8 @@ int a6xx_gmu_resume(struct a6xx_gpu *a6xx_gpu) pm_runtime_put(gmu->dev); } + mutex_unlock(&gmu->lock); + return ret; } diff --git a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c index 67dd2eeecf62..da300dce10fa 100644 --- a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c +++ b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c @@ -1914,9 +1914,7 @@ static int a6xx_gmu_pm_resume(struct msm_gpu *gpu) trace_msm_gpu_resume(0); - mutex_lock(&a6xx_gpu->gmu.lock); ret = a6xx_gmu_resume(a6xx_gpu); - mutex_unlock(&a6xx_gpu->gmu.lock); if (ret) return ret; -- 2.41.0