public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Yinghai Lu <yinghai@kernel.org>
To: Matt Mackall <mpm@selenic.com>
Cc: Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	Linus Torvalds <torvalds@osdl.org>, Ingo Molnar <mingo@elte.hu>
Subject: Re: random.c changes for sparse irq_desc are crap
Date: Wed, 31 Dec 2008 15:07:52 -0800	[thread overview]
Message-ID: <495BFB48.8080506@kernel.org> (raw)
In-Reply-To: <1230748169.19620.132.camel@calx>

Matt Mackall wrote:
> I just noticed you merged a change that pointlessly converts two
> random.c functions into ugly random.h inlines without going through the
> maintainer.
> 
> I also don't like the look of the newly-introduced sparse variants of
> these functions. Failure to find an irq descriptor in
> get_timer_rand_state is a BUG_ON should-never-happen sort of condition,
> not something to silently ignore. Letting the code try to dereference
> NULL is preferred here: we'll actually be able to find and fix the
> broken driver that's throwing around meaningless irq vectors.
> 
> Throwing away the timer_state pointer in the set_timer_rand_state
> function is similarly bogus in addition to being a memory leak.
> 
> Please fix this up.
> 

want something like this?

---
 include/linux/random.h |    6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

Index: linux-2.6/include/linux/random.h
===================================================================
--- linux-2.6.orig/include/linux/random.h
+++ linux-2.6/include/linux/random.h
@@ -75,8 +75,7 @@ static inline struct timer_rand_state *g
 
 	desc = irq_to_desc(irq);
 
-	if (!desc)
-		return NULL;
+	BUG_ON(!desc);
 
 	return desc->timer_rand_state;
 }
@@ -87,8 +86,7 @@ static inline void set_timer_rand_state(
 
 	desc = irq_to_desc(irq);
 
-	if (!desc)
-		return;
+	BUG_ON(!desc);
 
 	desc->timer_rand_state = state;
 }

  reply	other threads:[~2008-12-31 23:08 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-12-31 18:29 random.c changes for sparse irq_desc are crap Matt Mackall
2008-12-31 23:07 ` Yinghai Lu [this message]
2008-12-31 23:40   ` Matt Mackall
2009-01-01  0:14     ` Yinghai Lu
2009-01-01  9:31       ` Matt Mackall
2009-01-02 15:59         ` Ingo Molnar
2009-01-03  8:06           ` [PATCH] sparseirq: move set/get_timer_rand_state back to .c Yinghai Lu

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=495BFB48.8080506@kernel.org \
    --to=yinghai@kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@elte.hu \
    --cc=mpm@selenic.com \
    --cc=torvalds@osdl.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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox