A broken guest can specify physical addresses that correspond
to any memory region, but it shouldn't be able to change ROM.
Signed-off-by: NDr. David Alan Gilbert <dgilbert@redhat.com>
Cc: qemu-stable@nongnu.org
Acked-by: NPaolo Bonzini <pbonzini@redhat.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

Dataplane has been omitting forever the step of setting ISR when
an interrupt is raised.  This caused little breakage, because the
specification actually says that ISR may not be updated in MSI mode.

Some versions of the Windows drivers however didn't clear MSI mode
correctly, and proceeded using polling mode (using ISR, not the used
ring index!) for crashdump and hibernation.  If it were just crashdump
and hibernation it would not be a big deal, but recent releases of
Windows do not really shut down, but rather log out and hibernate to
make the next startup faster.  Hence, this manifested as a more serious
hang during shutdown with e.g. Windows 8.1 and virtio-win 1.8.0 RPMs.
Newer versions fixed this, while older versions do not use MSI at all.

The failure has always been there for virtio dataplane, but it became
visible after commits 9ffe337c ("virtio-blk: always use dataplane path
if ioeventfd is active", 2016-10-30) and ad07cd69 ("virtio-scsi: always
use dataplane path if ioeventfd is active", 2016-10-30) made virtio-blk
and virtio-scsi always use the dataplane code under KVM.  The good news
therefore is that it was not a bug in the patches---they were doing
exactly what they were meant for, i.e. shake out remaining dataplane bugs.

The fix is not hard, so it's worth arranging for the broken drivers.
The virtio_should_notify+event_notifier_set pair that is common to
virtio-blk and virtio-scsi dataplane is replaced with a new public
function virtio_notify_irqfd that also sets ISR.  The irqfd emulation
code now need not set ISR anymore, so virtio_irq is removed.
Reviewed-by: NStefan Hajnoczi <stefanha@redhat.com>
Tested-by: NFarhan Ali <alifm@linux.vnet.ibm.com>
Tested-by: NAlex Williamson <alex.williamson@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

The trace points for hw/virtio/virtio-balloon.c were mistakenly put
in the top level trace-events file, instead of util/trace-events in

  commit 270ab88f
  Author: Daniel P. Berrange <berrange@redhat.com>
  Date:   Thu Jun 16 09:39:57 2016 +0100

    trace: split out trace events for hw/virtio/ directory
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-id: 1473872624-23285-5-git-send-email-berrange@redhat.com
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

Documentation is docs/tracing.txt instead of docs/trace-events.txt.

find . -name trace-events -exec \
     sed -i "s?See docs/trace-events.txt for syntax documentation.?See docs/tracing.txt for syntax documentation.?" \
     {} \;
Signed-off-by: NLaurent Vivier <lvivier@redhat.com>
Message-id: 1470669081-17860-1-git-send-email-lvivier@redhat.com
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

Move all trace-events for files in the hw/virtio/ directory to
their own file.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>
Message-id: 1466066426-16657-12-git-send-email-berrange@redhat.com
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>