On 8/20/2024 8:09 PM, Alex Deucher wrote:
By moving locking and unlocking of the mutex to the gfx_v11_0_soft_reset function (the caller). This ensures that the mutex is always unlocked, regardless of whether (indicated by if (i >= adev->usec_timeout)) succeeds or fails.Otherwise we can fail to drop the software mutex when we fail to take the hardware mutex. Fixes: 76acba7b7f12 ("drm/amdgpu/gfx11: add a mutex for the gfx semaphore") Reported-by: Dan Carpenter <[email protected]> Signed-off-by: Alex Deucher <[email protected]> --- drivers/gpu/drm/amd/amdgpu/gfx_v11_0.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/amd/amdgpu/gfx_v11_0.c b/drivers/gpu/drm/amd/amdgpu/gfx_v11_0.c index 5704ad25a49d6..aa7fdece8ad42 100644 --- a/drivers/gpu/drm/amd/amdgpu/gfx_v11_0.c +++ b/drivers/gpu/drm/amd/amdgpu/gfx_v11_0.c @@ -4747,8 +4747,6 @@ int gfx_v11_0_request_gfx_index_mutex(struct amdgpu_device *adev, { u32 i, tmp, val;- if (req)- mutex_lock(&adev->gfx.reset_sem_mutex); for (i = 0; i < adev->usec_timeout; i++) { /* Request with MeId=2, PipeId=0 */ tmp = REG_SET_FIELD(0, CP_GFX_INDEX_MUTEX, REQUEST, req); @@ -4769,8 +4767,6 @@ int gfx_v11_0_request_gfx_index_mutex(struct amdgpu_device *adev, } udelay(1); } - if (!req) - mutex_unlock(&adev->gfx.reset_sem_mutex);if (i >= adev->usec_timeout)return -EINVAL; @@ -4818,8 +4814,10 @@ static int gfx_v11_0_soft_reset(void *handle) mutex_unlock(&adev->srbm_mutex);/* Try to acquire the gfx mutex before access to CP_VMID_RESET */+ mutex_lock(&adev->gfx.reset_sem_mutex); r = gfx_v11_0_request_gfx_index_mutex(adev, true); if (r) { + mutex_unlock(&adev->gfx.reset_sem_mutex); DRM_ERROR("Failed to acquire the gfx mutex during soft reset\n"); return r; } @@ -4834,6 +4832,7 @@ static int gfx_v11_0_soft_reset(void *handle)/* release the gfx mutex */r = gfx_v11_0_request_gfx_index_mutex(adev, false); + mutex_unlock(&adev->gfx.reset_sem_mutex); if (r) { DRM_ERROR("Failed to release the gfx mutex during soft reset\n"); return r;
Acked-by: Srinivasan Shanmugam <[email protected]>
