On Tue, 14 Jun 2022 00:05:55 -0700, Saurabh Sengar wrote:
> Current code is based on the idea that the max number of SGL entries
> also determines the max size of an I/O request. While this idea was
> true in older versions of the storvsc driver when SGL entry length
> was limited to 4 Kbytes, commit 3d9c3dcc58e9 ("scsi: storvsc: Enable
> scatterlist entry lengths > 4Kbytes") removed that limitation. It's
> now theoretically possible for the block layer to send requests that
> exceed the maximum size supported by Hyper-V. This problem doesn't
> currently happen in practice because the block layer defaults to a
> 512 Kbyte maximum, while Hyper-V in Azure supports 2 Mbyte I/O sizes.
> But some future configuration of Hyper-V could have a smaller max I/O
> size, and the block layer could exceed that max.
>
> [...]
Applied to 5.19/scsi-fixes, thanks!
[1/1] scsi: storvsc: Correct reporting of Hyper-V I/O size limits
https://git.kernel.org/mkp/scsi/c/1d3e0980782f
--
Martin K. Petersen Oracle Linux Engineering
