Messages in this thread | | | Date | Wed, 22 May 2013 18:19:35 +0200 | From | Peter Zijlstra <> | Subject | Re: [PATCH] kernel/sched/core.c: need return NULL when BUG() is defined as empty. |
| |
On Wed, May 22, 2013 at 02:33:17PM +0100, Russell King - ARM Linux wrote: > On Wed, May 22, 2013 at 11:11:56AM +0200, Peter Zijlstra wrote: > > On Mon, May 20, 2013 at 03:48:53PM +0800, Chen Gang wrote: > > > > > > When neither CONFIG_BUG nor HAVE_ARCH_BUG is defined, need let function > > > return failure value ('NULL') instead of random value. > > > > What will such a kernel do? Happily continue running whenever we hit a > > BUG? that seems like a particularly bad idea. Should we not have a stub > > BUG() function like: > > > > void BUG(void) __attribute__((noreturn)) > > { > > local_irq_disable(); > > while (1) ; > > } > > Eww. So you've a platform where you have things like panic_on_oops > enabled, and you hit this bug... do we really want to just stop? > Wouldn't replacing BUG() with panic("BUG"); be better ? > > But, this begs the question - what is the point of being able to turn > off BUG() ? As BUG() on any sensible architecture is implemented by > placing the minimum of code at the callsite (eg, one instruction if > not using verbose) anything like the above is likely to be bigger. > > So, I'd actually argue that rather than trying to "fix" this, get rid > of CONFIG_BUG and make it always enabled everywhere - just like what > has recently been done with hotplug.
Works for me.
| |