From: Christoph Hellwig <hch@lst.de>
To: Kevin Wolf <kwolf@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>, qemu-devel@nongnu.org
Subject: Re: [Qemu-devel] [PATCH] block: prevent multiwrite_merge from creating too large iovecs
Date: Wed, 20 Jan 2010 17:24:34 +0100 [thread overview]
Message-ID: <20100120162434.GA7212@lst.de> (raw)
In-Reply-To: <4B56EB0F.2020409@redhat.com>
On Wed, Jan 20, 2010 at 12:37:51PM +0100, Kevin Wolf wrote:
> Am 19.01.2010 22:15, schrieb Christoph Hellwig:
> > If we go over the maximum number of iovecs support by syscall we get
> > back EINVAL from the kernel which translate to I/O errors for the guest.
> >
> > Signed-off-by: Christoph Hellwig <hch@lst.de>
>
> Is this really enough? We don't check for IOV_MAX in any other place, so
> can't we get a too big request directly from virtio-blk?
Currently the virtqueue is limited to 1024 iovecs, but I plan to put in
some better infrastructure to deal with the queue limit. For now this
patch fixes an issue that we see with real life setups.
next prev parent reply other threads:[~2010-01-20 16:24 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-01-19 21:15 [Qemu-devel] [PATCH] block: prevent multiwrite_merge from creating too large iovecs Christoph Hellwig
2010-01-20 11:37 ` Kevin Wolf
2010-01-20 16:24 ` Christoph Hellwig [this message]
2010-01-20 16:29 ` Kevin Wolf
2010-01-26 9:21 ` Christoph Hellwig
2010-01-26 13:08 ` Anthony Liguori
2010-01-26 13:42 ` Christoph Hellwig
2010-01-20 14:56 ` Anthony Liguori
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