On Tue, 20 Aug 2019 09:33:24 -0700 Kees Cook <keescook@xxxxxxxxxxxx> wrote: > > > > diff --git a/lib/bug.c b/lib/bug.c > > > > index 1077366f496b..6c22e8a6f9de 100644 > > > > --- a/lib/bug.c > > > > +++ b/lib/bug.c > > > > @@ -181,6 +181,15 @@ enum bug_trap_type report_bug(unsigned long bugaddr, struct pt_regs *regs) > > > > } > > > > } > > > > + /* > > > > + * BUG() and WARN_ON() families don't print a custom debug message > > > > + * before triggering the exception handler, so we must add the > > > > + * "cut here" line now. WARN() issues its own "cut here" before the > > > > + * extra debugging message it writes before triggering the handler. > > > > + */ > > > > + if ((bug->flags & BUGFLAG_PRINTK) == 0) > > > > + printk(KERN_DEFAULT CUT_HERE); > > > > > > I'm not loving that BUGFLAG_PRINTK name, BUGFLAG_CUT_HERE makes more > > > sense to me. > > That's fine -- easy rename. :) > > > Actually it would be BUGFLAG_NO_CUT_HERE then, otherwise all arches not > > using the generic macros will have to add the flag to get the "cut here" > > line. > > I am testing for the lack of the flag (so that only the > CONFIG_GENERIC_BUG with __WARN_FLAGS case needs to set it). I was > thinking of the flag to mean "this reporting flow has already issued > cut-here". It sounds like it would be more logical to have it named > BUGFLAG_NO_CUT_HERE to mean "do not issue a cut-here; it has already > happened"? I will update the patch. > BUGFLAG_HAS_CUT_HERE ? As it shows it was already done? -- Steve
