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Date: Wed, 14 Nov 2018 11:49:34 +0100
From: Kevin Wolf <kwolf@redhat.com>
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Subject: Re: [Qemu-devel] [for 3.1? PATCH] qcow2: Assert that refcount block
 offsets fit in the refcount table
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To: Alberto Garcia <berto@igalia.com>
Cc: Eric Blake <eblake@redhat.com>, qemu-devel@nongnu.org, qemu-block@nongnu.org, Max Reitz <mreitz@redhat.com>

Am 14.11.2018 um 08:10 hat Alberto Garcia geschrieben:
> On Tue 13 Nov 2018 06:06:54 PM CET, Eric Blake <eblake@redhat.com> wrote:
> 
> >> Refcount table entries have a field to store the offset of the
> >> refcount block. The rest of the bits of the entry are currently
> >> reserved.
> >> 
> >> The offset is always taken from the entry using REFT_OFFSET_MASK to
> >> ensure that we only use the bits that belong to that field.
> >> 
> >> While that mask is used every time we read from the refcount table, it
> >> is never used when we write to it. Due to the other constraints of the
> >> qcow2 format QEMU can never produce refcount block offsets that don't
> >> fit in that field so any such offset when allocating a refcount block
> >> would indicate a bug in QEMU.

Missing S-o-b.

> >>   block/qcow2-refcount.c | 3 +++
> >>   1 file changed, 3 insertions(+)
> >> 
> >
> > Reviewed-by: Eric Blake <eblake@redhat.com>
> 
> Yes, for 3.1, shall I resend it with the updated subject message?

Honestly, I don't see why an additional assertion should qualify as a
fix? If it changes the behaviour, it's a bug.

You wouldn't have to resend for the updated subject message, but you do
for the missing S-o-b.

Kevin