Re: [PATCH v2] virtio_blk: Fix an SG_IO regression

[Bart Van Assche <Bart.VanAssche@wdc.com>]

On Wed, 2017-10-25 at 11:23 -0700, Jens Axboe wrote:
> On 10/25/2017 02:56 AM, Bart Van Assche wrote:
> > Avoid that submitting an SG_IO ioctl triggers a kernel oops that
> > is preceded by:
> > 
> > usercopy: kernel memory overwrite attempt detected to (null) (<null>) (6 bytes)
> > kernel BUG at mm/usercopy.c:72!
> 
> Seems I saw a note on a runtime oops triggered by this patch yesterday,
> but now I can't seem to find it... Did you see it?

Do you perhaps want me to add the stack trace from the following e-mail to
the patch description: https://marc.info/?l=linux-arm-kernel&m=150854010321833 ?

> > diff --git a/drivers/block/Kconfig b/drivers/block/Kconfig
> > index 4a438b8abe27..b0b2100763bf 100644
> > --- a/drivers/block/Kconfig
> > +++ b/drivers/block/Kconfig
> > @@ -450,6 +450,7 @@ config VIRTIO_BLK_SCSI
> >  	bool "SCSI passthrough request for the Virtio block driver"
> >  	depends on VIRTIO_BLK
> >  	select BLK_SCSI_REQUEST
> > +	select SCSI_MOD
> 
> Should this be SCSI? That's what libata does. It may be correct as-is,
> didn't look too deeply, just curious why it's different.

That is what I came up with after having had a look at drivers/scsi/Makefile.
But after having checked drivers/scsi/Kconfig I think we indeed need to select
SCSI instead of SCSI_MOD.

Bart.