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From: Stefan Hajnoczi <stefanha@redhat.com>
To: Hanna Czenczek <hreitz@redhat.com>
Cc: qemu-block@nongnu.org, qemu-devel@nongnu.org,
	Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>,
	Eric Blake <eblake@redhat.com>, Kevin Wolf <kwolf@redhat.com>,
	Fam Zheng <fam@euphon.net>
Subject: Re: [RFC 0/2] Split padded I/O vectors exceeding IOV_MAX
Date: Wed, 15 Mar 2023 11:29:41 -0400	[thread overview]
Message-ID: <20230315152941.GD16636@fedora> (raw)
In-Reply-To: <20230315121330.29679-1-hreitz@redhat.com>

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On Wed, Mar 15, 2023 at 01:13:28PM +0100, Hanna Czenczek wrote:
> Hi,
> 
> We accept I/O vectors with up to 1024 (IOV_MAX) elements from guests.
> When a guest request does not conform to the underlying storage's
> alignment requirements, we pad it with head and/or tail buffers as
> necessary, which are simply appended to the I/O vector.
> 
> As of 4c002cef, we (sensibly) check that such-padded vectors do not then
> exceed IOV_MAX.  However, there seems to be no sensible error handling;
> instead, the guest simply receives an I/O error.
> 
> That???s a problem, because it submitted a perfectly sensible I/O request

Looks like there is an encoding issue. I get 3 question marks instead of
an apostrophe. lore.kernel.org also renders mojibake:
https://lore.kernel.org/qemu-devel/20230315121330.29679-1-hreitz@redhat.com/

Stefan

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  parent reply	other threads:[~2023-03-15 15:30 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-03-15 12:13 [RFC 0/2] Split padded I/O vectors exceeding IOV_MAX Hanna Czenczek
2023-03-15 12:13 ` [RFC 1/2] block: " Hanna Czenczek
2023-03-15 18:25   ` Eric Blake
2023-03-16  9:43     ` Hanna Czenczek
2023-03-15 18:48   ` Stefan Hajnoczi
2023-03-16 10:10     ` Hanna Czenczek
2023-03-16 17:44   ` Vladimir Sementsov-Ogievskiy
2023-03-17  8:05     ` Hanna Czenczek
2023-03-15 12:13 ` [RFC 2/2] iotests/iov-padding: New test Hanna Czenczek
2023-03-15 15:29 ` Stefan Hajnoczi [this message]
2023-03-15 16:05   ` [RFC 0/2] Split padded I/O vectors exceeding IOV_MAX Hanna Czenczek

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