From: Jan Kara <jack@suse.cz>
Subject: Re: freeze_bdev hangs
Date: Tue, 9 Oct 2012 23:49:15 +0200
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Cc: Jan Kara <jack@suse.cz>, Eric Sandeen <sandeen@redhat.com>,
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To: Prashant Shah <pshah.mumbai@gmail.com>
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On Mon 08-10-12 22:05:38, Prashant Shah wrote:
> Hi,
> 
> On Mon, Oct 8, 2012 at 9:49 PM, Jan Kara <jack@suse.cz> wrote:
> >   And what tool are you using for monitoring?
> 
> I am using printk(). A custom module that changes the make_request_fn
> of the block device to a custom callback. In the callback I am
> printing the request bio details and passing the bio back to the
> original make_request_fn.
  OK. There are several ways how I could imagine you hit ino == 0. Either
someone is using direct IO or inode is a block device inode...

								Honza