[Qemu-devel] [PATCH] pci: improve w1c mask handling

["Michael S. Tsirkin" <mst@redhat.com>]

- save/restore must not check w1c bits
  since they are in fact guest controlled
- clear w1c bits on reset

Note: for express there are different kinds of
reset, some leave part of config space alone.
We will likely need a sticky bit mask to implement this.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---

Isaku, does the below make sense?

 hw/pci.c |    6 ++++--
 1 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/hw/pci.c b/hw/pci.c
index e50de14..1a14a0e 100644
--- a/hw/pci.c
+++ b/hw/pci.c
@@ -141,7 +141,8 @@ static void pci_device_reset(PCIDevice *dev)
     pci_update_irq_status(dev);
     /* Clear all writeable bits */
     pci_word_test_and_clear_mask(dev->config + PCI_COMMAND,
-                                 pci_get_word(dev->wmask + PCI_COMMAND));
+                                 pci_get_word(dev->wmask + PCI_COMMAND) |
+                                 pci_get_word(dev->w1cmask + PCI_COMMAND));
     dev->config[PCI_CACHE_LINE_SIZE] = 0x0;
     dev->config[PCI_INTERRUPT_LINE] = 0x0;
     for (r = 0; r < PCI_NUM_REGIONS; ++r) {
@@ -293,7 +294,8 @@ static int get_pci_config_device(QEMUFile *f, void *pv, size_t size)
 
     qemu_get_buffer(f, config, size);
     for (i = 0; i < size; ++i) {
-        if ((config[i] ^ s->config[i]) & s->cmask[i] & ~s->wmask[i]) {
+        if ((config[i] ^ s->config[i]) &
+            s->cmask[i] & ~s->wmask[i] & ~s->w1cmask) {
             qemu_free(config);
             return -EINVAL;
         }
-- 
1.7.3.2.91.g446ac