mirror of https://github.com/torvalds/linux.git
3563d85531
The previous fix for the circlular lock splat about the busyness
worker wasn't quite complete. Even though the reset-in-progress flag
is cleared at the start of intel_uc_reset_finish, the entire function
is still inside the reset mutex lock. Not sure why the patch appeared
to fix the issue both locally and in CI. However, it is now back
again.
There is a further complication that the wedge code path within
intel_gt_reset() jumps around so much that it results in nested
reset_prepare/_finish calls. That is, the call sequence is:
intel_gt_reset
| reset_prepare
| __intel_gt_set_wedged
| | reset_prepare
| | reset_finish
| reset_finish
The nested finish means that even if the clear of the in-progress flag
was moved to the end of _finish, it would still be clear for the
entire second call. Surprisingly, this does not seem to be causing any
other problems at present.
As an aside, a wedge on fini does not call the finish functions at
all. The reset_in_progress flag is left set (twice).
So instead of trying to cancel the worker anywhere at all in the reset
path, just add a cancel to intel_guc_submission_fini instead. Note
that it is not a problem if the worker is still active during a reset.
Either it will run before the reset path starts locking things and
will simply block the reset code for a tiny amount of time. Or it will
run after the locks have been acquired and will early exit due to the
try-lock.
Also, do not use the reset-in-progress flag to decide whether a
synchronous cancel is safe (from a lockdep perspective) or not.
Instead, use the actual reset mutex state (both the genuine one and
the custom rolled BACKOFF one).
Fixes:
|
||
|---|---|---|
| Documentation | ||
| LICENSES | ||
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| io_uring | ||
| ipc | ||
| kernel | ||
| lib | ||
| mm | ||
| net | ||
| rust | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| .rustfmt.toml | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
README
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.