CVS commit: src/sys/external/bsd/drm2/linux

["Taylor R Campbell" <riastradh%netbsd.org@localhost>]

Module Name:    src
Committed By:   riastradh
Date:           Sat Nov  7 14:05:02 UTC 2026

Modified Files:
        src/sys/external/bsd/drm2/linux: linux_ww_mutex.c

Log Message:
linux ww_mutex: Nix another assertion that trips in sketchy path.

Under the premise (explained in the comment above) that it is
legitimate for the upstream Linux code to do ww_mutex_trylock on a
mutex already held by the current thread, we can't assert

        mutex->wwm_state != WW_WANTOWN ||
            mutex->wwm_u.ctx->wwx_owner != curlwp

any more than we can assert

        mutex->wwm_state != WW_CTX ||
            mutex->wwm_u.ctx->wwx_owner != curlwp

because if the latter condition is possible, then any concurrent
thread tries to acquire the mutex a moment before we test that
condition will turn it into the former condition, i.e., transition to
mutex->wwm_state = WW_WANTOWN with mutex->wwm_u.ctx->wwx_owner =
curlwp.

PR kern/60926: amdgpu triggers assert in ww_mutex, disabling makes it
mostly stable (raven ridge)


To generate a diff of this commit:
cvs rdiff -u -r1.17 -r1.18 src/sys/external/bsd/drm2/linux/linux_ww_mutex.c

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.