From: Will Deacon Date: Fri, 19 Oct 2012 13:03:33 +0000 (+0100) Subject: virtio: force vring descriptors to be allocated from lowmem X-Git-Tag: v3.8-rc1~28^2~24 X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=b92b1b89a33c172c075edccf6afb0edc41d851fd;p=pandora-kernel.git virtio: force vring descriptors to be allocated from lowmem Virtio devices may attempt to add descriptors to a virtqueue from atomic context using GFP_ATOMIC allocation. This is problematic because such allocations can fall outside of the lowmem mapping, causing virt_to_phys to report bogus physical addresses which are subsequently passed to userspace via the buffers for the virtual device. This patch masks out __GFP_HIGH and __GFP_HIGHMEM from the requested flags when allocating descriptors for a virtqueue. If an atomic allocation is requested and later fails, we will return -ENOSPC which will be handled by the driver. Cc: stable@kernel.org Cc: Sasha Levin Signed-off-by: Will Deacon Signed-off-by: Rusty Russell --- Reading git-diff-tree failed