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Date: Fri, 12 Feb 2010 14:50:44 +0100
From: Christoph Hellwig <hch@lst.de>
Subject: Re: [Qemu-devel] Heads up: glibc preadv emulation breaks qemu on
	older kernels
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To: malc <av1474@comtv.ru>
Cc: qemu-devel@nongnu.org, Christoph Hellwig <hch@lst.de>, "Richard W.M. Jones" <rjones@redhat.com>

On Fri, Feb 12, 2010 at 04:49:23PM +0300, malc wrote:
> On Fri, 12 Feb 2010, Christoph Hellwig wrote:
> 
> > On Thu, Feb 11, 2010 at 07:06:08PM +0000, Richard W.M. Jones wrote:
> > > One interesting thing is that qemu has its own preadv emulation (which
> > > does the emulation correctly), but this is never used because qemu
> > > never gets ENOSYS back from preadv.
> > 
> > At this point the amount of bugs in the glibc preadv/pwritev code really
> > make me want to go to use the raw system calls on Linux only.  Any
> > opinions from the maintainers if that is acceptable?
> 
> There are more than one way to parse the first sentence, if it should be
> read as:
>   On linux and on linux only avoid using pread/write[v] and talk to the
>   kernel directly.
> 
> Then i agree.

Yes.  The BSDs tend to not play stupid emulation games in the libc, so
changes of these kinds of messups to happen are far less.