Re: [Qemu-stable] [Qemu-block] [PATCH] scsi-generic: prevent guest from exceeding SG_IO limits

[Kevin Wolf]

Am 18.04.2019 um 13:01 hat Paolo Bonzini geschrieben:
> On 18/04/19 12:47, Kevin Wolf wrote:
> >> This is acually only an issue with kernels prior to 4.5, so it should be
> >> fixed downstream instead.
> >
> > I don't think that upstream QEMU has kernels > 4.5 as an official
> > requirement, though? We try to be compatible with quite old libs, so we
> > should stay compatible with old kernels, too.
> 
> It is a pretty rare case, where the host must support very large
> scatter/gather lists (>=1024 elements) and there is a workaround by
> setting max_sectors_kb to 4096 in the host.  It also makes performance
> worse.

Fair enough. I didn't consider that it has a performance impact even on
newer kernels that don't need the patch.

Kevin