From: Chris Wilson <[email protected]> commit 488751a0ef9b5ce572c47301ce62d54fc6b5a74d upstream.
On error we unpin and free the wa_ctx.vma, but do not clear any of the derived flags. During lrc_init, we look at the flags and attempt to dereference the wa_ctx.vma if they are set. To protect the error path where we try to limp along without the wa_ctx, make sure we clear those flags! Reported-by: Matt Roper <[email protected]> Fixes: 604a8f6f1e33 ("drm/i915/lrc: Only enable per-context and per-bb buffers if set") Signed-off-by: Chris Wilson <[email protected]> Cc: Matt Roper <[email protected]> Cc: Tvrtko Ursulin <[email protected]> Cc: Mika Kuoppala <[email protected]> Cc: <[email protected]> # v4.15+ Reviewed-by: Matt Roper <[email protected]> Link: https://patchwork.freedesktop.org/patch/msgid/[email protected] (cherry-picked from 5b4dc95cf7f573e927fbbd406ebe54225d41b9b2) Signed-off-by: Jani Nikula <[email protected]> Link: https://patchwork.freedesktop.org/patch/msgid/[email protected] Signed-off-by: Greg Kroah-Hartman <[email protected]> --- drivers/gpu/drm/i915/gt/intel_lrc.c | 3 +++ 1 file changed, 3 insertions(+) --- a/drivers/gpu/drm/i915/gt/intel_lrc.c +++ b/drivers/gpu/drm/i915/gt/intel_lrc.c @@ -3936,6 +3936,9 @@ err: static void lrc_destroy_wa_ctx(struct intel_engine_cs *engine) { i915_vma_unpin_and_release(&engine->wa_ctx.vma, 0); + + /* Called on error unwind, clear all flags to prevent further use */ + memset(&engine->wa_ctx, 0, sizeof(engine->wa_ctx)); } typedef u32 *(*wa_bb_func_t)(struct intel_engine_cs *engine, u32 *batch);
