From: Jani Nikula <jani.nikula@intel.com> stable inclusion from linux-4.19.202 commit 0dcd7a637489394fa0b8a55019da609f6b3c13d5 -------------------------------- commit 410ed5731a6566498a3aa904420aa2e49ba0ba90 upstream. Clang build with UBSAN enabled leads to the following build error: drivers/gpu/drm/i915/intel_engine_cs.o: In function `intel_engine_init_execlist': drivers/gpu/drm/i915/intel_engine_cs.c:411: undefined reference to `__compiletime_assert_411' Again, for this to work the code would first need to be inlined and then constant folded, which doesn't work for Clang because semantic analysis happens before optimization/inlining. Use GEM_BUG_ON() instead of BUILD_BUG_ON(). v2: Use is_power_of_2() from log2.h (Chris) References: http://mid.mail-archive.com/20181015203410.155997-1-swboyd@chromium.org Reported-by: Stephen Boyd <swboyd@chromium.org> Cc: Stephen Boyd <swboyd@chromium.org> Cc: Chris Wilson <chris@chris-wilson.co.uk> Tested-by: Nathan Chancellor <natechancellor@gmail.com> Tested-by: Stephen Boyd <swboyd@chromium.org> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Jani Nikula <jani.nikula@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20181016122938.18757-2-jani.ni... Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> --- drivers/gpu/drm/i915/intel_engine_cs.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/intel_engine_cs.c b/drivers/gpu/drm/i915/intel_engine_cs.c index 2d1952849d69f..12ade478533f4 100644 --- a/drivers/gpu/drm/i915/intel_engine_cs.c +++ b/drivers/gpu/drm/i915/intel_engine_cs.c @@ -463,7 +463,7 @@ static void intel_engine_init_execlist(struct intel_engine_cs *engine) struct intel_engine_execlists * const execlists = &engine->execlists; execlists->port_mask = 1; - BUILD_BUG_ON_NOT_POWER_OF_2(execlists_num_ports(execlists)); + GEM_BUG_ON(!is_power_of_2(execlists_num_ports(execlists))); GEM_BUG_ON(execlists_num_ports(execlists) > EXECLIST_MAX_PORTS); execlists->queue_priority = INT_MIN; -- 2.25.1