[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [PATCH v2 1/4] qcow2: Require that the virtual size is a multiple of

From: Max Reitz
Subject: Re: [PATCH v2 1/4] qcow2: Require that the virtual size is a multiple of the sector size
Date: Tue, 14 Jan 2020 14:01:03 +0100
User-agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.3.1

On 09.01.20 20:12, Alberto Garcia wrote:
> The qcow2 header specifies the virtual size of the image in bytes, but
> BlockDriverState stores it as a number of 512-byte sectors.
> If the user tries to create an image with a size that is not a
> multiple of the sector size then this is fixed on creation by
> silently rounding the image size up (see commit c2eb918e32).
> qcow2_co_truncate() is more strict and returns an error instead.
> However when an image is opened the virtual size is rounded down,
> which means that trying to access the last few advertised bytes will
> result in an error. As seen above QEMU cannot create such images and
> there's no good use case that would require us to try to handle them
> so let's just treat them as unsupported.

But isn’t that just a bug in qemu?


Attachment: signature.asc
Description: OpenPGP digital signature

reply via email to

[Prev in Thread] Current Thread [Next in Thread]