Re: [PATCH 1/23] Make register values available to panic notifiers

[David Howells <dhowells@redhat.com>]

David VomLehn <dvomlehn@cisco.com> wrote:

> +NORET_TYPE void panic(const char *fmt, ...)
> +{
> +	va_list args;
> +	const struct pt_regs *regs;
> +	int i;
> +
> +	preempt_disable();
> +	bust_spinlocks(1);
> +	regs = save_ptregs(&__get_cpu_var(panic_panic_regs));
> +	va_start(args, fmt);
> +	vpanic_with_regs(regs, fmt, args);
> +	/* Since vpanic_with_regs doesn't return, we skip va_end() */
> +	/* Infinite loop so compiler doesn't complain about this returning */
> +	for (i = 0; ; )
> +		mdelay(1);
> +}

Can the use of va_start() clobber lots of registers, thereby rendering the
exercise pointless on some arches?

Also, can the save_ptregs() function be out of line asm?  The FRV constructed
inline statement is huge (and wrong).

David