The driver may sleep with holding a spinlock.
The function call paths (from bottom to top) in Linux-4.17 are:
[FUNC] mutex_lock_nested
drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c, 1477:
mutex_lock_nested in amdgpu_dpm_enable_uvd
drivers/gpu/drm/amd/amdgpu/amdgpu_uvd.c, 1154:
amdgpu_dpm_enable_uvd in amdgpu_uvd_ring_begin_use
drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c, 80:
[FUNC_PTR]amdgpu_uvd_ring_begin_use in amdgpu_ring_alloc
drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c, 199:
amdgpu_ring_alloc in amdgpu_virt_kiq_wreg
drivers/gpu/drm/amd/amdgpu/amdgpu_device.c, 207:
amdgpu_virt_kiq_wreg in amdgpu_mm_wreg
drivers/gpu/drm/amd/amdgpu/vi.c, 207:
amdgpu_mm_wreg in vi_gc_cac_rreg
drivers/gpu/drm/amd/amdgpu/vi.c, 206:
_raw_spin_lock_irqsave in vi_gc_cac_rreg
[FUNC] mutex_lock_nested
drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c, 1477:
mutex_lock_nested in amdgpu_dpm_enable_uvd
drivers/gpu/drm/amd/amdgpu/amdgpu_uvd.c, 1154:
amdgpu_dpm_enable_uvd in amdgpu_uvd_ring_begin_use
drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c, 80:
[FUNC_PTR]amdgpu_uvd_ring_begin_use in amdgpu_ring_alloc
drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c, 199:
amdgpu_ring_alloc in amdgpu_virt_kiq_wreg
drivers/gpu/drm/amd/amdgpu/amdgpu_device.c, 207:
amdgpu_virt_kiq_wreg in amdgpu_mm_wreg
drivers/gpu/drm/amd/amdgpu/soc15.c, 106:
amdgpu_mm_wreg in soc15_pcie_rreg
drivers/gpu/drm/amd/amdgpu/soc15.c, 105:
_raw_spin_lock_irqsave in soc15_pcie_rreg
[FUNC] mutex_lock_nested
drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c, 1477:
mutex_lock_nested in amdgpu_dpm_enable_uvd
drivers/gpu/drm/amd/amdgpu/amdgpu_uvd.c, 1154:
amdgpu_dpm_enable_uvd in amdgpu_uvd_ring_begin_use
drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c, 80:
[FUNC_PTR]amdgpu_uvd_ring_begin_use in amdgpu_ring_alloc
drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c, 199:
amdgpu_ring_alloc in amdgpu_virt_kiq_wreg
drivers/gpu/drm/amd/amdgpu/amdgpu_device.c, 207:
amdgpu_virt_kiq_wreg in amdgpu_mm_wreg
drivers/gpu/drm/amd/amdgpu/cik.c, 139:
amdgpu_mm_wreg in cik_uvd_ctx_wreg
drivers/gpu/drm/amd/amdgpu/cik.c, 138:
_raw_spin_lock_irqsave in cik_uvd_ctx_wreg
[FUNC] mutex_lock_nested
drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c, 1477:
mutex_lock_nested in amdgpu_dpm_enable_uvd
drivers/gpu/drm/amd/amdgpu/amdgpu_uvd.c, 1154:
amdgpu_dpm_enable_uvd in amdgpu_uvd_ring_begin_use
drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c, 80:
[FUNC_PTR]amdgpu_uvd_ring_begin_use in amdgpu_ring_alloc
drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c, 199:
amdgpu_ring_alloc in amdgpu_virt_kiq_wreg
drivers/gpu/drm/amd/amdgpu/amdgpu_device.c, 207:
amdgpu_virt_kiq_wreg in amdgpu_mm_wreg
drivers/gpu/drm/amd/amdgpu/dce_v6_0.c, 126:
amdgpu_mm_wreg in dce_v6_0_audio_endpt_rreg
drivers/gpu/drm/amd/amdgpu/dce_v6_0.c, 125:
_raw_spin_lock_irqsave in dce_v6_0_audio_endpt_rreg
Note that [FUNC_PTR] means a function pointer call is used.
These bugs are found by my static analysis tool DSAC.
Best wishes,
Jia-Ju Bai