tree 76a19e32d603dcc0936313fbb9e5a1de759a159d
parent 94dfbdb3894eda2f673b70e20da2743c4a8d3968
author Avi Kivity <avi@qumranet.com> 1173880494 +0200
committer Avi Kivity <avi@qumranet.com> 1178178752 +0300

KVM: Remove extraneous guest entry on mmio read

When emulating an mmio read, we actually emulate twice: once to determine
the physical address of the mmio, and, after we've exited to userspace to
get the mmio value, we emulate again to place the value in the result
register and update any flags.

But we don't really need to enter the guest again for that, only to take
an immediate vmexit.  So, if we detect that we're doing an mmio read,
emulate a single instruction before entering the guest again.

Signed-off-by: Avi Kivity <avi@qumranet.com>