Re: [PATCH v5 0/9] Introduce Xe PCIe FLR

[Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>]

On 4/6/2026 7:07 AM, Raag Jadav wrote:
> Here's my humble attempt at introducing PCIe Function Level Reset (FLR)
> support in xe driver. This is ofcourse a half baked implementation and
> only limited to re-initializing GT. This needs to be extended for a lot
> of different components which I've skipped here for my lack of competence,
> so feel free to join in and support them.

I'm jumping in to review a bit late, sorry for that.

I think we need a comment (both here and in code) to detail exactly what 
we expect to happen around the FLR (or let me know if it's already 
somewhere because I couldn't spot it). Which objects are expected to 
survive, which ones do we need to recover or discard (and why)?
I'll sprinkle a few question in the relevant patches.

Daniele

>
> PS: All xe_exec_basic tests and clpeak run smoothly after FLR. Give it
> a spin and let me know if any regressions.
>
> Trigger it with:
>
> $ echo 1 > /sys/bus/pci/devices/<BDF>/reset
>
> v2: Re-initialize migrate context (Matthew Brost)
>      Add kernel doc (Matthew Brost)
>      Spell out Function Level Reset (Jani)
>
> v3: Cancel in-flight jobs before FLR
>
> v4: Teardown exec queues instead of mangling scheduler pending list (Matthew Brost)
>
> v5: Re-initialize kernel queues through submission backend (Matthew Brost)
>      Prevent PM ref leak for wedged device (Matthew Brost)
>
> Raag Jadav (9):
>    drm/xe/uc_fw: Allow re-initializing firmware
>    drm/xe/guc_submit: Introduce guc_exec_queue_reinit()
>    drm/xe/gt: Introduce FLR helpers
>    drm/xe/irq: Introduce xe_irq_disable()
>    drm/xe: Introduce xe_device_assert_lmem_ready()
>    drm/xe/bo_evict: Introduce xe_bo_restore_map()
>    drm/xe/exec_queue: Introduce xe_exec_queue_reinit()
>    drm/xe/migrate: Introduce xe_migrate_reinit()
>    drm/xe/pci: Introduce PCIe FLR
>
>   drivers/gpu/drm/xe/Makefile              |   1 +
>   drivers/gpu/drm/xe/xe_bo_evict.c         |  51 ++++++--
>   drivers/gpu/drm/xe/xe_bo_evict.h         |   2 +
>   drivers/gpu/drm/xe/xe_device.c           |  10 +-
>   drivers/gpu/drm/xe/xe_device.h           |   1 +
>   drivers/gpu/drm/xe/xe_device_types.h     |   3 +
>   drivers/gpu/drm/xe/xe_exec_queue.c       |  37 +++++-
>   drivers/gpu/drm/xe/xe_exec_queue.h       |   1 +
>   drivers/gpu/drm/xe/xe_exec_queue_types.h |   2 +
>   drivers/gpu/drm/xe/xe_gpu_scheduler.h    |   5 +
>   drivers/gpu/drm/xe/xe_gsc.c              |  14 ++
>   drivers/gpu/drm/xe/xe_gsc.h              |   1 +
>   drivers/gpu/drm/xe/xe_gt.c               |  47 +++++++
>   drivers/gpu/drm/xe/xe_gt.h               |   2 +
>   drivers/gpu/drm/xe/xe_gt_types.h         |   9 ++
>   drivers/gpu/drm/xe/xe_guc.c              |  29 ++++
>   drivers/gpu/drm/xe/xe_guc.h              |   2 +
>   drivers/gpu/drm/xe/xe_guc_submit.c       |  11 ++
>   drivers/gpu/drm/xe/xe_huc.c              |  14 ++
>   drivers/gpu/drm/xe/xe_huc.h              |   1 +
>   drivers/gpu/drm/xe/xe_irq.c              |  13 +-
>   drivers/gpu/drm/xe/xe_irq.h              |   1 +
>   drivers/gpu/drm/xe/xe_lrc.c              |  17 +++
>   drivers/gpu/drm/xe/xe_lrc.h              |   2 +
>   drivers/gpu/drm/xe/xe_migrate.c          |  12 ++
>   drivers/gpu/drm/xe/xe_migrate.h          |   1 +
>   drivers/gpu/drm/xe/xe_pci.c              |   1 +
>   drivers/gpu/drm/xe/xe_pci.h              |   2 +
>   drivers/gpu/drm/xe/xe_pci_err.c          | 160 +++++++++++++++++++++++
>   drivers/gpu/drm/xe/xe_uc.c               |  37 ++++++
>   drivers/gpu/drm/xe/xe_uc.h               |   2 +
>   drivers/gpu/drm/xe/xe_uc_fw.c            |  39 +++++-
>   drivers/gpu/drm/xe/xe_uc_fw.h            |   1 +
>   33 files changed, 510 insertions(+), 21 deletions(-)
>   create mode 100644 drivers/gpu/drm/xe/xe_pci_err.c
>