From mboxrd@z Thu Jan  1 00:00:00 1970
From: Amit Shah <amit.shah@redhat.com>
Subject: Re: [PATCH] virtio-console: avoid DMA from stack
Date: Wed, 1 Feb 2017 19:17:12 +0530
Message-ID: <20170201134712.GA7935@amit-lp.rh>
References: <075115ddd99246ffc4228a3e050ba68eb36c6a8c.1485935920.git.osandov@fb.com>
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To: Omar Sandoval <osandov@osandov.com>
Cc: kernel-team@fb.com, "Michael S. Tsirkin" <mst@redhat.com>, linux-kernel@vger.kernel.org, virtualization@lists.linux-foundation.org
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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