From: Kevin Wolf <kwolf@redhat.com>
To: Christoph Hellwig <hch@lst.de>
Cc: qemu-devel@nongnu.org
Subject: Re: [Qemu-devel] [PATCH] block: prevent multiwrite_merge from creating too large iovecs
Date: Wed, 20 Jan 2010 12:37:51 +0100 [thread overview]
Message-ID: <4B56EB0F.2020409@redhat.com> (raw)
In-Reply-To: <20100119211539.GA4383@lst.de>
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?
What about handling it transparently in qemu_pwritev/preadv and
laio_submit? Logically, it's a limitation of the backend anyway and not
a generic restriction.
To underline that it's a backend/platform dependent thing: Your patch
breaks the mingw build for me.
Kevin
next prev parent reply other threads:[~2010-01-20 11:39 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 [this message]
2010-01-20 16:24 ` Christoph Hellwig
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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