Re: [PATCH] Add hard/soft lockup debugger entry points

[Chris Metcalf]

On 1/25/2016 9:36 PM, Jeff Merkey wrote:
> This patch adds an export which can be set by system debuggers to direct
> the hard lockup and soft lockup detector to trigger an INT3 exception
> and enter a debugger if one is active.  It is assumed that if someone
> sets this variable, then an int3 handler of some sort will be actively
> loaded or registered via the notify die handler chain.
>
> This addition is extremely useful for debugging hard and soft lockups
> real time and quickly from a console debugger.
>
> Signed-off-by: Jeff Merkey<linux.mdb@xxxxxxxxx>
> ---
>   kernel/watchdog.c | 9 +++++++++
>   1 file changed, 9 insertions(+)

Introducing Intel-specific assembly into generic code won't work. You would
need to add a framework to allow platforms to specify a debugging instruction
or maybe leverage some existing framework like arch_kgdb_breakpoint.

--
Chris Metcalf, EZChip Semiconductor
http://www.ezchip.com