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

From: Peter Zijlstra <[email-masked]>
Date: Tue, 24 Mar 2020 22:13:03 +0100

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... :/