Re: [PATCH] virtio-console: avoid DMA from stack

From: Omar Sandoval
Date: Wed Mar 01 2017 - 15:11:10 EST


On Wed, Feb 01, 2017 at 07:17:12PM +0530, Amit Shah wrote:
> On (Wed) 01 Feb 2017 [00:02:27], Omar Sandoval wrote:
> > From: Omar Sandoval <osandov@xxxxxx>
> >
> > put_chars() stuffs the buffer it gets into an sg, but that buffer may be
> > on the stack. This breaks with CONFIG_VMAP_STACK=y (for me, it
> > manifested as printks getting turned into NUL bytes).
>
> Seems reasonable. I wonder since all implementations of hvc do a
> memcpy, if we can abstract it - but that'll need some work.
>
> Reviewed-by: Amit Shah <amit.shah@xxxxxxxxxx>
>
> Michael, please add to the virtio queue.
>
> Amit

Hi, Michael,

I don't see this in Linus' master or in your git tree, is it going to go
in for -rc1?

Thanks.