On Thu, Apr 30, 2020 at 07:28:58PM -0500, Josh Poimboeuf wrote:
> On Thu, Apr 30, 2020 at 04:05:07PM +0200, Arnd Bergmann wrote:
> > lib/locking-selftest.o: warning: objtool: locking_selftest()+0x117f: PUSHF
> > stack exhausted
> > lib/locking-selftest.o: warning: objtool: ww_tests()+0x1083: PUSHF stack
> > exhausted
>
> Peter,
>
> These functions have a bunch of irqs_disabled() checks, which means a
> bunch of PUSHFs with no POPFs.
>
> Am I reading it correctly that objtool assumes PUSHF is always paired
> with POPF? irqs_disabled() doesn't do that.
Right, it sorta does. I wonder why this shows up with GCC-10 though, and
not before.
Anyway, the sneaky fix here would be something like this.
diff --git a/lib/locking-selftest.c b/lib/locking-selftest.c
index 14f44f59e733..510656c776d9 100644
--- a/lib/locking-selftest.c
+++ b/lib/locking-selftest.c
@@ -1138,7 +1138,7 @@ static void dotest(void (*testcase_fn)(void), int
expected, int lockclass_mask)
{
unsigned long saved_preempt_count = preempt_count();
- WARN_ON(irqs_disabled());
+ lockdep_assert_irqs_enabled();
testcase_fn();
/*
