From 16af1e7f5ea64160fa831118d3ae73b4ba1c2452 Mon Sep 17 00:00:00 2001 From: Tomi Valkeinen Date: Wed, 20 Sep 2023 15:57:17 +0300 Subject: [PATCH] Revert "drm/omapdrm: Annotate dma-fence critical section in commit path" [ Upstream commit 9d7c8c066916f231ca0ed4e4fce6c4b58ca3e451 ] This reverts commit 250aa22920cd5d956a5d3e9c6a43d671c2bae217. The DMA-fence annotations cause a lockdep warning (see below). As per https://patchwork.freedesktop.org/patch/462170/ it sounds like the annotations don't work correctly. ====================================================== WARNING: possible circular locking dependency detected 6.5.0-rc2+ #2 Not tainted ------------------------------------------------------ kmstest/219 is trying to acquire lock: c4705838 (&hdmi->lock){+.+.}-{3:3}, at: hdmi5_bridge_mode_set+0x1c/0x50 but task is already holding lock: c11e1128 (dma_fence_map){++++}-{0:0}, at: omap_atomic_commit_tail+0x14/0xbc which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (dma_fence_map){++++}-{0:0}: __dma_fence_might_wait+0x48/0xb4 dma_resv_lockdep+0x1b8/0x2bc do_one_initcall+0x68/0x3b0 kernel_init_freeable+0x260/0x34c kernel_init+0x14/0x140 ret_from_fork+0x14/0x28 -> #1 (fs_reclaim){+.+.}-{0:0}: fs_reclaim_acquire+0x70/0xa8 __kmem_cache_alloc_node+0x3c/0x368 kmalloc_trace+0x28/0x58 _drm_do_get_edid+0x7c/0x35c hdmi5_bridge_get_edid+0xc8/0x1ac drm_bridge_connector_get_modes+0x64/0xc0 drm_helper_probe_single_connector_modes+0x170/0x528 drm_client_modeset_probe+0x208/0x1334 __drm_fb_helper_initial_config_and_unlock+0x30/0x548 omap_fbdev_client_hotplug+0x3c/0x6c drm_client_register+0x58/0x94 pdev_probe+0x544/0x6b0 platform_probe+0x58/0xbc really_probe+0xd8/0x3fc __driver_probe_device+0x94/0x1f4 driver_probe_device+0x2c/0xc4 __device_attach_driver+0xa4/0x11c bus_for_each_drv+0x84/0xdc __device_attach+0xac/0x20c bus_probe_device+0x8c/0x90 device_add+0x588/0x7e0 platform_device_add+0x110/0x24c platform_device_register_full+0x108/0x15c dss_bind+0x90/0xc0 try_to_bring_up_aggregate_device+0x1e0/0x2c8 __component_add+0xa4/0x174 hdmi5_probe+0x1c8/0x270 platform_probe+0x58/0xbc really_probe+0xd8/0x3fc __driver_probe_device+0x94/0x1f4 driver_probe_device+0x2c/0xc4 __device_attach_driver+0xa4/0x11c bus_for_each_drv+0x84/0xdc __device_attach+0xac/0x20c bus_probe_device+0x8c/0x90 deferred_probe_work_func+0x8c/0xd8 process_one_work+0x2ac/0x6e4 worker_thread+0x30/0x4ec kthread+0x100/0x124 ret_from_fork+0x14/0x28 -> #0 (&hdmi->lock){+.+.}-{3:3}: __lock_acquire+0x145c/0x29cc lock_acquire.part.0+0xb4/0x258 __mutex_lock+0x90/0x950 mutex_lock_nested+0x1c/0x24 hdmi5_bridge_mode_set+0x1c/0x50 drm_bridge_chain_mode_set+0x48/0x5c crtc_set_mode+0x188/0x1d0 omap_atomic_commit_tail+0x2c/0xbc commit_tail+0x9c/0x188 drm_atomic_helper_commit+0x158/0x18c drm_atomic_commit+0xa4/0xe8 drm_mode_atomic_ioctl+0x9a4/0xc38 drm_ioctl+0x210/0x4a8 sys_ioctl+0x138/0xf00 ret_fast_syscall+0x0/0x1c other info that might help us debug this: Chain exists of: &hdmi->lock --> fs_reclaim --> dma_fence_map Possible unsafe locking scenario: CPU0 CPU1 ---- ---- rlock(dma_fence_map); lock(fs_reclaim); lock(dma_fence_map); lock(&hdmi->lock); *** DEADLOCK *** 3 locks held by kmstest/219: #0: f1011de4 (crtc_ww_class_acquire){+.+.}-{0:0}, at: drm_mode_atomic_ioctl+0xf0/0xc38 #1: c47059c8 (crtc_ww_class_mutex){+.+.}-{3:3}, at: modeset_lock+0xf8/0x230 #2: c11e1128 (dma_fence_map){++++}-{0:0}, at: omap_atomic_commit_tail+0x14/0xbc stack backtrace: CPU: 1 PID: 219 Comm: kmstest Not tainted 6.5.0-rc2+ #2 Hardware name: Generic DRA74X (Flattened Device Tree) unwind_backtrace from show_stack+0x10/0x14 show_stack from dump_stack_lvl+0x58/0x70 dump_stack_lvl from check_noncircular+0x164/0x198 check_noncircular from __lock_acquire+0x145c/0x29cc __lock_acquire from lock_acquire.part.0+0xb4/0x258 lock_acquire.part.0 from __mutex_lock+0x90/0x950 __mutex_lock from mutex_lock_nested+0x1c/0x24 mutex_lock_nested from hdmi5_bridge_mode_set+0x1c/0x50 hdmi5_bridge_mode_set from drm_bridge_chain_mode_set+0x48/0x5c drm_bridge_chain_mode_set from crtc_set_mode+0x188/0x1d0 crtc_set_mode from omap_atomic_commit_tail+0x2c/0xbc omap_atomic_commit_tail from commit_tail+0x9c/0x188 commit_tail from drm_atomic_helper_commit+0x158/0x18c drm_atomic_helper_commit from drm_atomic_commit+0xa4/0xe8 drm_atomic_commit from drm_mode_atomic_ioctl+0x9a4/0xc38 drm_mode_atomic_ioctl from drm_ioctl+0x210/0x4a8 drm_ioctl from sys_ioctl+0x138/0xf00 sys_ioctl from ret_fast_syscall+0x0/0x1c Exception stack(0xf1011fa8 to 0xf1011ff0) 1fa0: 00466d58 be9ab510 00000003 c03864bc be9ab510 be9ab4e0 1fc0: 00466d58 be9ab510 c03864bc 00000036 00466ef0 00466fc0 00467020 00466f20 1fe0: b6bc7ef4 be9ab4d0 b6bbbb00 b6cb2cc0 Fixes: 250aa22920cd ("drm/omapdrm: Annotate dma-fence critical section in commit path") Reviewed-by: Aradhya Bhatia Signed-off-by: Tomi Valkeinen Link: https://patchwork.freedesktop.org/patch/msgid/20230920-dma-fence-annotation-revert-v1-2-7ebf6f7f5bf6@ideasonboard.com Signed-off-by: Sasha Levin --- drivers/gpu/drm/omapdrm/omap_drv.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) diff --git a/drivers/gpu/drm/omapdrm/omap_drv.c b/drivers/gpu/drm/omapdrm/omap_drv.c index afeeb77..e000577 100644 --- a/drivers/gpu/drm/omapdrm/omap_drv.c +++ b/drivers/gpu/drm/omapdrm/omap_drv.c @@ -69,7 +69,6 @@ static void omap_atomic_commit_tail(struct drm_atomic_state *old_state) { struct drm_device *dev = old_state->dev; struct omap_drm_private *priv = dev->dev_private; - bool fence_cookie = dma_fence_begin_signalling(); dispc_runtime_get(priv->dispc); @@ -92,6 +91,8 @@ static void omap_atomic_commit_tail(struct drm_atomic_state *old_state) omap_atomic_wait_for_completion(dev, old_state); drm_atomic_helper_commit_planes(dev, old_state, 0); + + drm_atomic_helper_commit_hw_done(old_state); } else { /* * OMAP3 DSS seems to have issues with the work-around above, @@ -101,11 +102,9 @@ static void omap_atomic_commit_tail(struct drm_atomic_state *old_state) drm_atomic_helper_commit_planes(dev, old_state, 0); drm_atomic_helper_commit_modeset_enables(dev, old_state); - } - drm_atomic_helper_commit_hw_done(old_state); - - dma_fence_end_signalling(fence_cookie); + drm_atomic_helper_commit_hw_done(old_state); + } /* * Wait for completion of the page flips to ensure that old buffers -- 2.7.4