Re: linux-next: Tree for Mar 20 (objtool warnings)

From: Peter Zijlstra
Date: Tue Mar 24 2020 - 17:13:15 EST


On Tue, Mar 24, 2020 at 10:53:05AM -0700, Randy Dunlap wrote:
> >> kernel/kcov.o: warning: objtool: __sanitizer_cov_trace_pc()+0x89: call to __ubsan_handle_load_invalid_value() with UACCESS enabled
> >>
>
> config-r1510 is attached.
> and kcov.o is attached.

I'm thinking this is because of commit:

0d6958a70483 kcov: collect coverage from interrupts

Which has:

@@ -1230,6 +1230,9 @@ struct task_struct {

+ bool kcov_softirq;

@@ -145,9 +157,10 @@ static notrace bool check_kcov_mode(enum kcov_mode needed_mode, struct task_stru

+ if (!in_task() && !(in_serving_softirq() && t->kcov_softirq))

And this __ubsan_handle_load_invalid_value() is verifying a bool is 0,1.

Another reason to hate on _Bool I suppose...

Let me see what to do about that... :/