[Qemu-devel] [PATCH] virtio-pci: thinko fix

2010-01-11 Thread Michael S. Tsirkin 
Since patch ed757e140c0ada220f213036e4497315d24ca8bct, virtio will
sometimes clear all status registers on bus master disable, which loses
information such as VIRTIO_CONFIG_S_FAILED bit.  This is a result of
a patch being misapplied: code uses !  instead of ~ for bit
operations as in Yan's original patch.  This obviously does not make
sense.

Signed-off-by: Michael S. Tsirkin m...@redhat.com
---

 hw/virtio-pci.c |2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/hw/virtio-pci.c b/hw/virtio-pci.c
index d222ce0..f4f1bc1 100644
--- a/hw/virtio-pci.c
+++ b/hw/virtio-pci.c
@@ -374,7 +374,7 @@ static void virtio_write_config(PCIDevice *pci_dev, 
uint32_t address,
 
 if (PCI_COMMAND == address) {
 if (!(val  PCI_COMMAND_MASTER)) {
-proxy-vdev-status = !VIRTIO_CONFIG_S_DRIVER_OK;
+proxy-vdev-status = ~VIRTIO_CONFIG_S_DRIVER_OK;
 }
 }
 
-- 
1.6.6.rc1.43.gf55cc

Re: [Qemu-devel] [PATCH] virtio-pci: thinko fix

2010-01-11 Thread Anthony Liguori 

On 01/11/2010 09:57 AM, Michael S. Tsirkin wrote:

Since patch ed757e140c0ada220f213036e4497315d24ca8bct, virtio will
sometimes clear all status registers on bus master disable, which loses
information such as VIRTIO_CONFIG_S_FAILED bit.  This is a result of
a patch being misapplied: code uses !  instead of ~ for bit
operations as in Yan's original patch.  This obviously does not make
sense.
   


Actually, the original patch used '!'.  It didn't carry a Signed-off-by 
and when it was reposted with a SoB, this was changed to '~'.  There was 
no indication though that the contents of the patch was different.


Moral of the story is, when you make a change to the patch, add a (v2) 
and state in the commit message what change was made.


Thanks for catching this.

Regards,

Anthony Liguori