From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christoph Hellwig <hch@infradead.org>
Subject: Re: raw disks no longer work in latest kvm (kvm-88 was fine)
Date: Sun, 7 Mar 2010 12:34:06 -0500
Message-ID: <20100307173406.GA3756@infradead.org>
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Cc: Christoph Hellwig <hch@infradead.org>,
	Antoine Martin <antoine@nagafix.co.uk>,
	Michael Tokarev <mjt@tls.msk.ru>, kvm@vger.kernel.org
To: Avi Kivity <avi@redhat.com>
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On Sun, Mar 07, 2010 at 07:30:06PM +0200, Avi Kivity wrote:
> It may also be that glibc is emulating preadv, incorrectly.

I've done a quick audit of all pathes leading to pread and all seem
to align correctly.  So either a broken glibc emulation or something
else outside the block layer seems likely.

> Antoine, can you check this?  ltrace may help, or run 'strings libc.so |  
> grep pread'.

Or just add an

#undef CONFIG_PREADV

just before the first

#ifdef CONFIG_PREADV

in posix-aio-compat.c and see if that works.