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

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

On Wed, 2017-10-25 at 12:34 -0700, Jens Axboe wrote:
> On 10/25/2017 12:25 PM, Bart Van Assche wrote:
> > 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 ?
> 
> It was an oops reported against the current patch, unless I'm mistaken. Hard
> to say, when I can't find the email this morning, may have been deleted...
> That's why I asked if you saw it.

Just found it: a570843ee9 ("virtio_blk: Fix an SG_IO regression"): kernel BUG at
include/linux/scatterlist.h:92! (https://lkml.org/lkml/2017/10/24/1117). Will have
a look.

Bart.