mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
synced 2026-04-29 09:22:53 -04:00
68ace460c5
We evaluate *active, which is a pointer into execlists->inflight[] during dequeue to decide how long a preempt-timeout we need to apply. However, as soon as we do the submit_ports, the HW may send its ACK interrupt causing us to promote execlists->pending[] tp execlists->inflight[], overwriting the value of *active. We know *active is only stable until we submit (as we only submit when there is no pending promotion). [ 16.102328] BUG: KCSAN: data-race in execlists_dequeue+0x1449/0x1600 [i915] [ 16.102356] [ 16.102375] race at unknown origin, with read to 0xffff8881e9500488 of 8 bytes by task 429 on cpu 1: [ 16.102780] execlists_dequeue+0x1449/0x1600 [i915] [ 16.103160] __execlists_submission_tasklet+0x48/0x60 [i915] [ 16.103540] execlists_submit_request+0x38e/0x3c0 [i915] [ 16.103940] submit_notify+0x8f/0xc0 [i915] [ 16.104308] __i915_sw_fence_complete+0x61/0x420 [i915] [ 16.104683] i915_sw_fence_complete+0x58/0x80 [i915] [ 16.105054] i915_sw_fence_commit+0x16/0x20 [i915] [ 16.105457] __i915_request_queue+0x60/0x70 [i915] [ 16.105843] i915_gem_do_execbuffer+0x2d6b/0x4230 [i915] [ 16.106227] i915_gem_execbuffer2_ioctl+0x2b0/0x580 [i915] [ 16.106257] drm_ioctl_kernel+0xe9/0x130 [ 16.106279] drm_ioctl+0x27d/0x45e [ 16.106311] ksys_ioctl+0x89/0xb0 [ 16.106336] __x64_sys_ioctl+0x42/0x60 [ 16.106370] do_syscall_64+0x6e/0x2c0 [ 16.106397] entry_SYSCALL_64_after_hwframe+0x44/0xa9 Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20200426094231.21995-1-chris@chris-wilson.co.uk
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.