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Date: Wed, 30 Apr 2014 13:57:05 -0700
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Subject: Re: dcache shrink list corruption?
From: Linus Torvalds <torvalds@linux-foundation.org>
To: Al Viro <viro@zeniv.linux.org.uk>
Cc: Miklos Szeredi <miklos@szeredi.hu>, Dave Chinner <david@fromorbit.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        linux-fsdevel <linux-fsdevel@vger.kernel.org>
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On Wed, Apr 30, 2014 at 1:38 PM, Al Viro <viro@zeniv.linux.org.uk> wrote:
>
> We do not (and cannot) call dentry_kill() with rcu_read_lock held - it can
> trigger any amount of IO, for one thing.  We can take it around the
> couple of places where do that spin_unlock(&dentry->d_lock) (along with
> setting DCACHE_RCUACCESS) - that's what I'd been refering to.

Just the last spin_unlock() would be the case that matters, if the
spin_unlock() is done on something that could be freed immediately and
the lock protects and is inside the entity that gets freed.

>   BTW, is there any convenient
> way to tell git commit --amend to update the commit date?  Something
> like --date=now would be nice, but it isn't accepted...

--date="$(date)" works.

The "--date" thing doesn't take the nice "git approxidate" strings,
maybe it should. So you have to give it a "real" date.

              Linus