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

From	Omar Sandoval <osandov@osandov.com>
Newsgroups	linux.kernel
Subject	Re: [PATCH] virtio-console: avoid DMA from stack
Date	2017-03-01 21:20 +0100
Message-ID	<tgiT7-89b-1@gated-at.bofh.it> (permalink)
References	<t5Y9k-3lP-23@gated-at.bofh.it> <t63sm-6Bo-5@gated-at.bofh.it>
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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@fb.com>
> > 
> > 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@redhat.com>
> 
> 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.

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Re: [PATCH] virtio-console: avoid DMA from stack Omar Sandoval <osandov@osandov.com> - 2017-03-01 21:20 +0100
  Re: [PATCH] virtio-console: avoid DMA from stack "Michael S. Tsirkin" <mst@redhat.com> - 2017-03-01 22:40 +0100

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