Re: [PATCH] [v2] arm64: define BUG() instruction without CONFIG_BUG

From: Catalin Marinas
Date: Wed Mar 22 2017 - 11:41:02 EST


On Wed, Mar 22, 2017 at 03:51:54PM +0100, Arnd Bergmann wrote:
> On Wed, Mar 22, 2017 at 3:37 PM, Catalin Marinas
> <catalin.marinas@xxxxxxx> wrote:
> > Hi Arnd,
> >
> > On Tue, Mar 14, 2017 at 10:39:21PM +0100, Arnd Bergmann wrote:
> >> This mirrors commit e9c38ceba8d9 ("ARM: 8455/1: define __BUG as
> >> asm(BUG_INSTR) without CONFIG_BUG") to make the behavior of
> >> arm64 consistent with arm and x86, and avoids lots of warnings in
> >> randconfig builds, such as:
> >>
> >> kernel/seccomp.c: In function '__seccomp_filter':
> >> kernel/seccomp.c:666:1: error: no return statement in function returning non-void [-Werror=return-type]
> >>
> >> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
> >
> > A side-effect of this patch is that it turns WARN into BUG. I hit the
> > WARN_ONCE in arch/arm64/kernel/efi.c:34 (on Juno with 64K pages) and
> > with your patch applied, the kernel panics.
>
> Taht was certainly not intended, and I don't see yet what exactly is going on.
> What is your setting for CONFIG_BUG and CONFIG_BUGVERBOSE?

CONFIG_BUG=y
CONFIG_DEBUG_BUGVERBOSE=y

(just defconfig + 64K pages)

--
Catalin