linux/include/uapi
Daniele Ceraolo Spurio 21784ca960 drm/xe/pxp: Clarify PXP queue creation behavior if PXP is not ready
The expected flow of operations when using PXP is to query the PXP
status and wait for it to transition to "ready" before attempting to
create an exec_queue. This flow is followed by the Mesa driver, but
there is no guarantee that an incorrectly coded (or malicious) app
will not attempt to create the queue first without querying the status.
Therefore, we need to clarify what the expected behavior of the queue
creation ioctl is in this scenario.

Currently, the ioctl always fails with an -EBUSY code no matter the
error, but for consistency it is better to distinguish between "failed
to init" (-EIO) and "not ready" (-EBUSY), the same way the query ioctl
does. Note that, while this is a change in the return code of an ioctl,
the behavior of the ioctl in this particular corner case was not clearly
spec'd, so no one should have been relying on it (and we know that Mesa,
which is the only known userspace for this, didn't).

v2: Minor rework of the doc (Rodrigo)

Fixes: 72d479601d ("drm/xe/pxp/uapi: Add userspace and LRC support for PXP-using queues")
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: John Harrison <John.C.Harrison@Intel.com>
Cc: José Roberto de Souza <jose.souza@intel.com>
Reviewed-by: José Roberto de Souza <jose.souza@intel.com>
Reviewed-by: John Harrison <John.C.Harrison@Intel.com>
Acked-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://lore.kernel.org/r/20250522225401.3953243-7-daniele.ceraolospurio@intel.com
History 2025-06-02 08:28:48 -07:00
..
asm-generic arm64 updates for 6.15: 2025-03-25 13:16:16 -07:00
cxl cxl: Add support for fwctl RPC command to enable CXL feature commands 2025-03-17 14:41:37 -03:00
drm drm/xe/pxp: Clarify PXP queue creation behavior if PXP is not ready 2025-06-02 08:28:48 -07:00
fwctl pds_fwctl: add rpc and query support 2025-03-21 20:57:55 -03:00
linux Merge drm/drm-next into drm-misc-next 2025-04-07 14:35:48 +02:00
misc cxl: Remove driver 2025-03-16 22:04:27 +11:00
mtd ubi: Expose interface for detailed erase counters 2025-01-18 15:32:32 +01:00
rdma RDMA/core: Add support to optional-counters binding configuration 2025-03-18 06:18:42 -04:00
regulator uapi: regulator: Fix typo 2024-01-04 13:22:24 +00:00
scsi scsi: cxlflash: Remove driver 2025-02-03 18:04:55 -05:00
sound ASoC: Intel: avs: Make PEAKVOL configurable from topology 2025-02-24 16:01:53 +00:00
video License cleanup: add SPDX license identifier to uapi header files with a license 2017-11-02 11:20:11 +01:00
xen xen/privcmd: Add new syscall to get gsi from dev 2024-09-25 09:54:55 +02:00
Kbuild kbuild: re-implement Makefile.headersinst without recursion 2019-06-15 19:57:02 +09:00