linux-kernel - Re: pdflush stuck in D state with v2.6.24-rc1-192-gef49c32

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <E1Inw51-0001e8-PS@localhost>
Date:	Fri, 2 Nov 2007 20:56:55 +0800
From:	Fengguang Wu <wfg@...l.ustc.edu.cn>
To:	Florin Iucha <florin@...ha.net>
Cc:	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
	Peter Zijlstra <peterz@...radead.org>
Subject: Re: pdflush stuck in D state with v2.6.24-rc1-192-gef49c32

On Thu, Nov 01, 2007 at 09:10:02PM -0500, Florin Iucha wrote:
> On Fri, Nov 02, 2007 at 09:33:21AM +0800, Fengguang Wu wrote:
> > > I will try that with a USB disk - I hope that won't make a difference.
> > 
> > Thank you. I guess a reiserfs on loop file would also be OK.
> > 
> > > > btw, what's the exact kernel version you are running?
> > > 
> > > I noticed it with the kernel in the $SUBJECT, as reported by 'git
> > > describe'.  I have pulled in new changesets since then.
> > 
> > And with the following patch applied?
> > 
> > ---
> >  fs/reiserfs/stree.c |    3 ---
> >  1 file changed, 3 deletions(-)
> > 
> > --- linux-2.6.24-git17.orig/fs/reiserfs/stree.c
> > +++ linux-2.6.24-git17/fs/reiserfs/stree.c
> > @@ -1458,9 +1458,6 @@ static void unmap_buffers(struct page *p
> >  				}
> >  				bh = next;
> >  			} while (bh != head);
> > -			if (PAGE_SIZE == bh->b_size) {
> > -				cancel_dirty_page(page, PAGE_CACHE_SIZE);
> > -			}
> >  		}
> >  	}
> >  }
> 
> ... and with the above patch applied.
> 
> Copying 300 MB from root (ext3) to the new file system did not trigger
> the pdflush condition.  But then I did a
>    cd $MOUNTPOINT && find . -exec md5sum {} \;
> and that brought one cpu to 75% iowait.

Immediately? Do you have the debug printk messages this time(with the
above patch)?

> I have attached my .config, if it helps.

It's really curious - I tried your .config and commands, and still
could not trigger the high iowait. I'm running 64bit Intel Core 2,
and kernel 2.6.24-rc1-git6 with the above patch.

Fengguang

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/