forked from Minki/linux
edbd7f318c
Lockdep reports a circular locking dependency with pages_lock taken in
the shrinker callback. The deadlock can't actually happen with current
users at least as a BO will never be purgeable when pages_lock is held.
To be safe, let's use mutex_trylock() instead and bail if a BO is locked
already.
WARNING: possible circular locking dependency detected
5.3.0-rc1+ #100 Tainted: G L
------------------------------------------------------
kswapd0/171 is trying to acquire lock:
000000009b9823fd (&shmem->pages_lock){+.+.}, at: drm_gem_shmem_purge+0x20/0x40
but task is already holding lock:
00000000f82369b6 (fs_reclaim){+.+.}, at: __fs_reclaim_acquire+0x0/0x40
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #1 (fs_reclaim){+.+.}:
fs_reclaim_acquire.part.18+0x34/0x40
fs_reclaim_acquire+0x20/0x28
__kmalloc_node+0x6c/0x4c0
kvmalloc_node+0x38/0xa8
drm_gem_get_pages+0x80/0x1d0
drm_gem_shmem_get_pages+0x58/0xa0
drm_gem_shmem_get_pages_sgt+0x48/0xd0
panfrost_mmu_map+0x38/0xf8 [panfrost]
panfrost_gem_open+0xc0/0xe8 [panfrost]
drm_gem_handle_create_tail+0xe8/0x198
drm_gem_handle_create+0x3c/0x50
panfrost_gem_create_with_handle+0x70/0xa0 [panfrost]
panfrost_ioctl_create_bo+0x48/0x80 [panfrost]
drm_ioctl_kernel+0xb8/0x110
drm_ioctl+0x244/0x3f0
do_vfs_ioctl+0xbc/0x910
ksys_ioctl+0x78/0xa8
__arm64_sys_ioctl+0x1c/0x28
el0_svc_common.constprop.0+0x90/0x168
el0_svc_handler+0x28/0x78
el0_svc+0x8/0xc
-> #0 (&shmem->pages_lock){+.+.}:
__lock_acquire+0xa2c/0x1d70
lock_acquire+0xdc/0x228
__mutex_lock+0x8c/0x800
mutex_lock_nested+0x1c/0x28
drm_gem_shmem_purge+0x20/0x40
panfrost_gem_shrinker_scan+0xc0/0x180 [panfrost]
do_shrink_slab+0x208/0x500
shrink_slab+0x10c/0x2c0
shrink_node+0x28c/0x4d8
balance_pgdat+0x2c8/0x570
kswapd+0x22c/0x638
kthread+0x128/0x130
ret_from_fork+0x10/0x18
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(fs_reclaim);
lock(&shmem->pages_lock);
lock(fs_reclaim);
lock(&shmem->pages_lock);
*** DEADLOCK ***
3 locks held by kswapd0/171:
#0: 00000000f82369b6 (fs_reclaim){+.+.}, at: __fs_reclaim_acquire+0x0/0x40
#1: 00000000ceb37808 (shrinker_rwsem){++++}, at: shrink_slab+0xbc/0x2c0
#2: 00000000f31efa81 (&pfdev->shrinker_lock){+.+.}, at: panfrost_gem_shrinker_scan+0x34/0x180 [panfrost]
Fixes:
|
||
|---|---|---|
| .. | ||
| bridge | ||
| i2c | ||
| ttm | ||
| amd_asic_type.h | ||
| ati_pcigart.h | ||
| drm_agpsupport.h | ||
| drm_atomic_helper.h | ||
| drm_atomic_state_helper.h | ||
| drm_atomic_uapi.h | ||
| drm_atomic.h | ||
| drm_audio_component.h | ||
| drm_auth.h | ||
| drm_blend.h | ||
| drm_bridge.h | ||
| drm_cache.h | ||
| drm_client.h | ||
| drm_color_mgmt.h | ||
| drm_connector.h | ||
| drm_crtc_helper.h | ||
| drm_crtc.h | ||
| drm_damage_helper.h | ||
| drm_debugfs_crc.h | ||
| drm_debugfs.h | ||
| drm_device.h | ||
| drm_displayid.h | ||
| drm_dp_dual_mode_helper.h | ||
| drm_dp_helper.h | ||
| drm_dp_mst_helper.h | ||
| drm_drv.h | ||
| drm_dsc.h | ||
| drm_edid.h | ||
| drm_encoder_slave.h | ||
| drm_encoder.h | ||
| drm_fb_cma_helper.h | ||
| drm_fb_helper.h | ||
| drm_file.h | ||
| drm_fixed.h | ||
| drm_flip_work.h | ||
| drm_format_helper.h | ||
| drm_fourcc.h | ||
| drm_framebuffer.h | ||
| drm_gem_cma_helper.h | ||
| drm_gem_framebuffer_helper.h | ||
| drm_gem_shmem_helper.h | ||
| drm_gem_vram_helper.h | ||
| drm_gem.h | ||
| drm_hashtab.h | ||
| drm_hdcp.h | ||
| drm_ioctl.h | ||
| drm_irq.h | ||
| drm_lease.h | ||
| drm_legacy.h | ||
| drm_mipi_dbi.h | ||
| drm_mipi_dsi.h | ||
| drm_mm.h | ||
| drm_mode_config.h | ||
| drm_mode_object.h | ||
| drm_modes.h | ||
| drm_modeset_helper_vtables.h | ||
| drm_modeset_helper.h | ||
| drm_modeset_lock.h | ||
| drm_of.h | ||
| drm_os_linux.h | ||
| drm_panel.h | ||
| drm_pci.h | ||
| drm_pciids.h | ||
| drm_plane_helper.h | ||
| drm_plane.h | ||
| drm_prime.h | ||
| drm_print.h | ||
| drm_probe_helper.h | ||
| drm_property.h | ||
| drm_rect.h | ||
| drm_scdc_helper.h | ||
| drm_self_refresh_helper.h | ||
| drm_simple_kms_helper.h | ||
| drm_syncobj.h | ||
| drm_sysfs.h | ||
| drm_util.h | ||
| drm_utils.h | ||
| drm_vblank.h | ||
| drm_vma_manager.h | ||
| drm_vram_mm_helper.h | ||
| drm_writeback.h | ||
| drmP.h | ||
| gma_drm.h | ||
| gpu_scheduler.h | ||
| i915_component.h | ||
| i915_drm.h | ||
| i915_mei_hdcp_interface.h | ||
| i915_pciids.h | ||
| intel_lpe_audio.h | ||
| intel-gtt.h | ||
| spsc_queue.h | ||