[Intel-gfx] [PATCH] kthread: finer-grained lockdep/cross-release completion

[Peter Zijlstra]

On Thu, Dec 07, 2017 at 11:08:49AM +0100, Daniel Vetter wrote:
> Since -rc1 we're hitting a bunch of lockdep splats using the new
> cross-release stuff around the 2 kthread completions. In all cases
> they are because totally independent uses of kthread are mixed up by
> lockdep into the same locking class, creating artificial deadlocks.
> 
> Fix this by converting kthread code in the same way as e.g.
> alloc_workqueue already works: Use macros for the public api so we can
> have a callsite specific lockdep key, then pass that through the
> entire callchain. Due to the many entry points this is slightly
> tedious.
> 
> Cc: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
> Cc: Marta Lofstedt <marta.lofstedt at intel.com>
> Cc: Byungchul Park <byungchul.park at lge.com>
> Cc: Ingo Molnar <mingo at kernel.org>
> Cc: Peter Zijlstra <peterz at infradead.org>
> Cc: Tejun Heo <tj at kernel.org>
> Cc: Kees Cook <keescook at chromium.org>
> Cc: Thomas Gleixner <tglx at linutronix.de>
> Cc: Shaohua Li <shli at fb.com>
> Cc: Andrew Morton <akpm at linux-foundation.org>
> Cc: Jens Axboe <axboe at kernel.dk>
> Cc: Daniel Vetter <daniel.vetter at ffwll.ch>
> Cc: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
> Cc: Jonathan Corbet <corbet at lwn.net>
> Cc: Oleg Nesterov <oleg at redhat.com>
> References: https://bugs.freedesktop.org/show_bug.cgi?id=103950
> Signed-off-by: Daniel Vetter <daniel.vetter at intel.com>

Acked-by: Peter Zijlstra (Intel) <peterz at infradead.org>