diff options
| author | Olivier Kaloudoff <olivier.kaloudoff@gmail.com> | 2026-10-13 20:53:11 +0200 |
|---|---|---|
| committer | Alex Deucher <alexander.deucher@amd.com> | 2026-10-27 17:02:38 -0400 |
| commit | 1233dd17f99c75787a31035656ecfeff80522421 (patch) | |
| tree | d77fe80cacb558a088820d310757607deec0cab4 /drivers/gpu | |
| parent | 90d91a192751cd9a7d9d2286299bc72ec1c28179 (diff) | |
drm/amdkfd: tear down KFD processes before early fini_sw on disconnect
On surprise removal, amdgpu_device_fini_hw() calls
amdgpu_amdkfd_device_fini_sw() when pci_dev_is_disconnected() is true.
fini_sw frees kfd.dev, but KFD processes may still be alive and hold
references to it: kfd_process_destroy() dereferences kfd.dev via
kfd_processes_remove(), and svm_range_list_fini() /
kfd_process_free_outstanding_kfd_bos() touch per-device SVM state.
The kfd_processes_count wait only happens later in
kgd2kfd_teardown_processes(), called from the top-half remove path
well after fini_sw. In the observed failure the killed KFD process
(SIGBUS on unplug) stuck in D state on its exit path, so
kfd_processes_count never drained and the PCIe removal thread wedged
permanently in cond_resched(), producing soft-lockup and hung-task
splats.
Tear KFD processes down before freeing kfd.dev on the disconnect
path, and guard kgd2kfd_teardown_processes() against kfd.dev already
being gone when it runs a second time.
Cc: Xiaogang Chen <xiaogang.chen@amd.com>
Signed-off-by: Olivier Kaloudoff <olivier.kaloudoff@gmail.com>
Signed-off-by: Felix Kuehling <felix.kuehling@amd.com>
Reviewed-by: Felix Kuehling <felix.kuehling@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit 836f44ba87ed7b1d83e2b7bfc788f8c6437b03a7)
Cc: stable@vger.kernel.org
Diffstat (limited to 'drivers/gpu')
| -rw-r--r-- | drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 5 | ||||
| -rw-r--r-- | drivers/gpu/drm/amd/amdkfd/kfd_device.c | 9 |
2 files changed, 12 insertions, 2 deletions
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c index f147c0c459da..c65bc575a57a 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c @@ -4331,8 +4331,11 @@ void amdgpu_device_fini_hw(struct amdgpu_device *adev) * before ip_fini_early to prevent kfd locking refcount issues by calling * amdgpu_amdkfd_suspend() */ - if (pci_dev_is_disconnected(adev->pdev)) + if (pci_dev_is_disconnected(adev->pdev)) { + /* Drain KFD processes while kfd.dev is still valid */ + amdgpu_amdkfd_teardown_processes(adev); amdgpu_amdkfd_device_fini_sw(adev); + } amdgpu_coredump_fini(adev); amdgpu_device_ip_fini_early(adev); diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_device.c b/drivers/gpu/drm/amd/amdkfd/kfd_device.c index bb4c6695f3cf..0f96c9e3fa4d 100644 --- a/drivers/gpu/drm/amd/amdkfd/kfd_device.c +++ b/drivers/gpu/drm/amd/amdkfd/kfd_device.c @@ -1814,7 +1814,14 @@ void kgd2kfd_teardown_processes(struct amdgpu_device *adev) mutex_unlock(&kfd_processes_mutex); - /* wait all kfd processes use adev terminate */ + /* kfd.dev may already be freed on surprise removal */ + if (!adev->kfd.dev) + return; + + /* + * Wait for all KFD processes using adev to terminate. Must be + * unbounded: device state is freed once they are gone. + */ while (!!atomic_read(&adev->kfd.dev->kfd_processes_count)) cond_resched(); } |