All of lore.kernel.org
 help / color / mirror / Atom feed
From: Peter Zijlstra <peterz@infradead.org>
To: Yang Shi <yang.shi@linaro.org>
Cc: mingo@redhat.com, linux-kernel@vger.kernel.org,
	linaro-kernel@lists.linaro.org
Subject: Re: [PATCH] panic: lockdep: correct lock debugging state check
Date: Tue, 26 Apr 2016 14:39:55 +0200	[thread overview]
Message-ID: <20160426123955.GT3448@twins.programming.kicks-ass.net> (raw)
In-Reply-To: <1461641797-9368-1-git-send-email-yang.shi@linaro.org>

On Mon, Apr 25, 2016 at 08:36:37PM -0700, Yang Shi wrote:
> When kernel oops happens, lock debugging is turned off by debug_locks_off()
> in oops_enter() via calling __debug_locks_off() which set debug_locks to 0
> via xchg(). But, calling to __debug_locks_off() to check lock debugging state
> in add_taint() called by oops_end() will always return false since xchg()
> returns the old value of debug_locks which is cleared in oops_enter() already.
> 
> This prevents add_taint() from printing out lock debugging disable information
> although LOCKDEP_NOW_UNRELIABLE is passed to it.
> 
> Check lock debugging state via !debug_locks to fix this. Although
> !__debug_locks_off() could do the same thing, it may look confusing.
> 
What are you smoking? This is the second completely insane patch you
send this week.

This breaks add_taint() and gains us nothing except trivialities. Who
bloody cares about that print if you've just had an OOPS.

  reply	other threads:[~2016-04-26 12:40 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-04-26  3:36 [PATCH] panic: lockdep: correct lock debugging state check Yang Shi
2016-04-26 12:39 ` Peter Zijlstra [this message]
2016-04-26 17:33   ` Shi, Yang

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20160426123955.GT3448@twins.programming.kicks-ass.net \
    --to=peterz@infradead.org \
    --cc=linaro-kernel@lists.linaro.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@redhat.com \
    --cc=yang.shi@linaro.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.