powerpc/64s: sreset panic if there is no debugger or crash dump handlers

[Michael Ellerman]

On Mon, 2018-03-26 at 15:01:16 UTC, Nicholas Piggin wrote:
> system_reset_exception does most of its own crash handling now,
> invoking the debugger or crash dumps if they are registered. If not,
> then it goes through to die() to print stack traces, and then is
> supposed to panic (according to comments).
> 
> However after die() prints oopses, it does its own handling which
> doesn't allow system_reset_exception to panic (e.g., it may just
> kill the current process). This patch causes sreset exceptions to
> return from die after it prints messages but before acting.
> 
> This also stops die from invoking the debugger on 0x100 crashes.
> system_reset_exception similarly calls the debugger. It had been
> thought this was harmless (because if the debugger was disabled,
> neither call would fire, and if it was enabled the first call
> would return). However in some cases like xmon 'X' command, the
> debugger returns 0, which currently causes it to be entered
> again (first in system_reset_exception, then in die), which is
> confusing.
> 
> Signed-off-by: Nicholas Piggin <npiggin at gmail.com>

Applied to powerpc next, thanks.

https://git.kernel.org/powerpc/c/d40b6768e45bd9213139b2d91d30c7

cheers