From: Hugh Dickins <hughd@xxxxxxxxxx> 5.15-rc1 crashes with blank screen when booting up on two ThinkPads using i915. Bisections converge convincingly, but arrive at different and surprising "culprits", none of them the actual culprit. netconsole (with init_netconsole() hacked to call i915_init() when logging has started, instead of by module_init()) tells the story: kernel BUG at drivers/gpu/drm/i915/i915_sw_fence.c:245! with RSI: ffffffff814d408b pointing to sw_fence_dummy_notify(). I've been building with CONFIG_CC_OPTIMIZE_FOR_SIZE=y, and that function needs to be 4-byte aligned. v2: (Jani Nikula) - Change BUG_ON to WARN_ON v3: (Jani / Tvrtko) - Short circuit __i915_sw_fence_init on WARN_ON v4: (Lucas) - Break WARN_ON changes out in a different patch Fixes: 62eaf0ae217d ("drm/i915/guc: Support request cancellation") Signed-off-by: Hugh Dickins <hughd@xxxxxxxxxx> Signed-off-by: Matthew Brost <matthew.brost@xxxxxxxxx> Reviewed-by: Matthew Brost <matthew.brost@xxxxxxxxx> --- drivers/gpu/drm/i915/gt/intel_context.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/i915/gt/intel_context.c b/drivers/gpu/drm/i915/gt/intel_context.c index ff637147b1a9..e7f78bc7ebfc 100644 --- a/drivers/gpu/drm/i915/gt/intel_context.c +++ b/drivers/gpu/drm/i915/gt/intel_context.c @@ -362,8 +362,8 @@ static int __intel_context_active(struct i915_active *active) return 0; } -static int sw_fence_dummy_notify(struct i915_sw_fence *sf, - enum i915_sw_fence_notify state) +static int __i915_sw_fence_call +sw_fence_dummy_notify(struct i915_sw_fence *sf, enum i915_sw_fence_notify state) { return NOTIFY_DONE; } -- 2.32.0