6.6-stable review patch. If anyone has any objections, please let me know.
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From: Tomi Valkeinen tomi.valkeinen@ideasonboard.com
[ Upstream commit ca34d816558c3e4c3f8fe037b5a6b16c944693de ]
This reverts commit 4d56a4f08391857ba93465de489707b66adad114.
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 6.6.0-rc2+ #1 Not tainted ------------------------------------------------------ kmstest/733 is trying to acquire lock: ffff8000819377f0 (fs_reclaim){+.+.}-{0:0}, at: __kmem_cache_alloc_node+0x58/0x2d4
but task is already holding lock: ffff800081a06aa0 (dma_fence_map){++++}-{0:0}, at: tidss_atomic_commit_tail+0x20/0xc0 [tidss]
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+0x5c/0xd0 dma_resv_lockdep+0x1a4/0x32c do_one_initcall+0x84/0x2fc kernel_init_freeable+0x28c/0x4c4 kernel_init+0x24/0x1dc ret_from_fork+0x10/0x20
-> #1 (mmu_notifier_invalidate_range_start){+.+.}-{0:0}: fs_reclaim_acquire+0x70/0xe4 __kmem_cache_alloc_node+0x58/0x2d4 kmalloc_trace+0x38/0x78 __kthread_create_worker+0x3c/0x150 kthread_create_worker+0x64/0x8c workqueue_init+0x1e8/0x2f0 kernel_init_freeable+0x11c/0x4c4 kernel_init+0x24/0x1dc ret_from_fork+0x10/0x20
-> #0 (fs_reclaim){+.+.}-{0:0}: __lock_acquire+0x1370/0x20d8 lock_acquire+0x1e8/0x308 fs_reclaim_acquire+0xd0/0xe4 __kmem_cache_alloc_node+0x58/0x2d4 __kmalloc_node_track_caller+0x58/0xf0 kmemdup+0x34/0x60 regmap_bulk_write+0x64/0x2c0 tc358768_bridge_pre_enable+0x8c/0x12d0 [tc358768] drm_atomic_bridge_call_pre_enable+0x68/0x80 [drm] drm_atomic_bridge_chain_pre_enable+0x50/0x158 [drm] drm_atomic_helper_commit_modeset_enables+0x164/0x264 [drm_kms_helper] tidss_atomic_commit_tail+0x58/0xc0 [tidss] commit_tail+0xa0/0x188 [drm_kms_helper] drm_atomic_helper_commit+0x1a8/0x1c0 [drm_kms_helper] drm_atomic_commit+0xa8/0xe0 [drm] drm_mode_atomic_ioctl+0x9ec/0xc80 [drm] drm_ioctl_kernel+0xc4/0x170 [drm] drm_ioctl+0x234/0x4b0 [drm] drm_compat_ioctl+0x110/0x12c [drm] __arm64_compat_sys_ioctl+0x128/0x150 invoke_syscall+0x48/0x110 el0_svc_common.constprop.0+0x40/0xe0 do_el0_svc_compat+0x1c/0x38 el0_svc_compat+0x48/0xb4 el0t_32_sync_handler+0xb0/0x138 el0t_32_sync+0x194/0x198
other info that might help us debug this:
Chain exists of: fs_reclaim --> mmu_notifier_invalidate_range_start --> dma_fence_map
Possible unsafe locking scenario:
CPU0 CPU1 ---- ---- rlock(dma_fence_map); lock(mmu_notifier_invalidate_range_start); lock(dma_fence_map); lock(fs_reclaim);
*** DEADLOCK ***
3 locks held by kmstest/733: #0: ffff800082e5bba0 (crtc_ww_class_acquire){+.+.}-{0:0}, at: drm_mode_atomic_ioctl+0x118/0xc80 [drm] #1: ffff000004224c88 (crtc_ww_class_mutex){+.+.}-{3:3}, at: modeset_lock+0xdc/0x1a0 [drm] #2: ffff800081a06aa0 (dma_fence_map){++++}-{0:0}, at: tidss_atomic_commit_tail+0x20/0xc0 [tidss]
stack backtrace: CPU: 0 PID: 733 Comm: kmstest Not tainted 6.6.0-rc2+ #1 Hardware name: Toradex Verdin AM62 on Verdin Development Board (DT) Call trace: dump_backtrace+0x98/0x118 show_stack+0x18/0x24 dump_stack_lvl+0x60/0xac dump_stack+0x18/0x24 print_circular_bug+0x288/0x368 check_noncircular+0x168/0x17c __lock_acquire+0x1370/0x20d8 lock_acquire+0x1e8/0x308 fs_reclaim_acquire+0xd0/0xe4 __kmem_cache_alloc_node+0x58/0x2d4 __kmalloc_node_track_caller+0x58/0xf0 kmemdup+0x34/0x60 regmap_bulk_write+0x64/0x2c0 tc358768_bridge_pre_enable+0x8c/0x12d0 [tc358768] drm_atomic_bridge_call_pre_enable+0x68/0x80 [drm] drm_atomic_bridge_chain_pre_enable+0x50/0x158 [drm] drm_atomic_helper_commit_modeset_enables+0x164/0x264 [drm_kms_helper] tidss_atomic_commit_tail+0x58/0xc0 [tidss] commit_tail+0xa0/0x188 [drm_kms_helper] drm_atomic_helper_commit+0x1a8/0x1c0 [drm_kms_helper] drm_atomic_commit+0xa8/0xe0 [drm] drm_mode_atomic_ioctl+0x9ec/0xc80 [drm] drm_ioctl_kernel+0xc4/0x170 [drm] drm_ioctl+0x234/0x4b0 [drm] drm_compat_ioctl+0x110/0x12c [drm] __arm64_compat_sys_ioctl+0x128/0x150 invoke_syscall+0x48/0x110 el0_svc_common.constprop.0+0x40/0xe0 do_el0_svc_compat+0x1c/0x38 el0_svc_compat+0x48/0xb4 el0t_32_sync_handler+0xb0/0x138 el0t_32_sync+0x194/0x198
Fixes: 4d56a4f08391 ("drm/tidss: Annotate dma-fence critical section in commit path") Reviewed-by: Aradhya Bhatia a-bhatia1@ti.com Signed-off-by: Tomi Valkeinen tomi.valkeinen@ideasonboard.com Link: https://patchwork.freedesktop.org/patch/msgid/20230920-dma-fence-annotation-... Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/tidss/tidss_kms.c | 4 ---- 1 file changed, 4 deletions(-)
diff --git a/drivers/gpu/drm/tidss/tidss_kms.c b/drivers/gpu/drm/tidss/tidss_kms.c index c979ad1af236..d096d8d2bc8f 100644 --- a/drivers/gpu/drm/tidss/tidss_kms.c +++ b/drivers/gpu/drm/tidss/tidss_kms.c @@ -4,8 +4,6 @@ * Author: Tomi Valkeinen tomi.valkeinen@ti.com */
-#include <linux/dma-fence.h> - #include <drm/drm_atomic.h> #include <drm/drm_atomic_helper.h> #include <drm/drm_bridge.h> @@ -25,7 +23,6 @@ static void tidss_atomic_commit_tail(struct drm_atomic_state *old_state) { struct drm_device *ddev = old_state->dev; struct tidss_device *tidss = to_tidss(ddev); - bool fence_cookie = dma_fence_begin_signalling();
dev_dbg(ddev->dev, "%s\n", __func__);
@@ -36,7 +33,6 @@ static void tidss_atomic_commit_tail(struct drm_atomic_state *old_state) drm_atomic_helper_commit_modeset_enables(ddev, old_state);
drm_atomic_helper_commit_hw_done(old_state); - dma_fence_end_signalling(fence_cookie); drm_atomic_helper_wait_for_flip_done(ddev, old_state);
drm_atomic_helper_cleanup_planes(ddev, old_state);