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From: Chris Metcalf <cmetcalf@ezchip.com>
To: Jeff Merkey <linux.mdb@gmail.com>, <linux-kernel@vger.kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>,
	Don Zickus <dzickus@redhat.com>,
	Ulrich Obergfell <uobergfe@redhat.com>,
	Aaron Tomlin <atomlin@redhat.com>, Michal Hocko <mhocko@suse.cz>,
	Frederic Weisbecker <fweisbec@gmail.com>,
	Tejun Heo <tj@kernel.org>,
	Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
Subject: Re: [PATCH] Add hard/soft lockup debugger entry points
Date: Mon, 25 Jan 2016 21:47:38 -0500	[thread overview]
Message-ID: <56A6DE4A.3060608@ezchip.com> (raw)
In-Reply-To: <20160126023607.GA5405@localhost.localdomain>

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@gmail.com>
> ---
>   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

  reply	other threads:[~2016-01-26  2:47 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-01-26  2:36 [PATCH] Add hard/soft lockup debugger entry points Jeff Merkey
2016-01-26  2:47 ` Chris Metcalf [this message]
2016-01-26  2:58   ` Jeff Merkey
2016-01-26  4:02 ` kbuild test robot
2016-01-26  4:23 ` kbuild test robot
2016-01-26  4:27 ` kbuild test robot
2016-01-26  4:55   ` Jeff Merkey

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