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[3/5] pci-assign: Fix dword read at PCI_COMMAND

Message ID 0fe595f76c6b3d72df01a575b26b754f6e411021.1303981185.git.jan.kiszka@siemens.com (mailing list archive)
State New, archived
Headers show

Commit Message

Jan Kiszka April 28, 2011, 8:59 a.m. UTC
If we emulate the command register, we must only read its content from
the shadow config space. For dword read of both PCI_COMMAND and
PCI_STATUS, at least the latter must be read from the device.

For simplicity reasons and as the code path is not considered
performance critical for the affected SRIOV devices, the fix performes
device access to the command word unconditionally, even if emulation is
enabled and only that word is read.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
---
 hw/device-assignment.c |    8 +++++---
 1 files changed, 5 insertions(+), 3 deletions(-)
diff mbox

Patch

diff --git a/hw/device-assignment.c b/hw/device-assignment.c
index f37f108..ee81434 100644
--- a/hw/device-assignment.c
+++ b/hw/device-assignment.c
@@ -482,14 +482,11 @@  static uint32_t assigned_dev_pci_read_config(PCIDevice *d, uint32_t address,
     /*
      * Catch access to
      *  - vendor & device ID
-     *  - command register (if emulation needed)
      *  - base address registers
      *  - ROM base address & capability pointer
      *  - interrupt line & pin
      */
     if (ranges_overlap(address, len, PCI_VENDOR_ID, 4) ||
-        (pci_dev->need_emulate_cmd &&
-         ranges_overlap(address, len, PCI_COMMAND, 2)) ||
         ranges_overlap(address, len, PCI_BASE_ADDRESS_0, 24) ||
         ranges_overlap(address, len, PCI_ROM_ADDRESS, 8) ||
         ranges_overlap(address, len, PCI_INTERRUPT_LINE, 2)) {
@@ -521,6 +518,11 @@  do_log:
     DEBUG("(%x.%x): address=%04x val=0x%08x len=%d\n",
           (d->devfn >> 3) & 0x1F, (d->devfn & 0x7), address, val, len);
 
+    if (pci_dev->need_emulate_cmd) {
+        val = merge_bits(val, pci_default_read_config(d, PCI_COMMAND, 2),
+                         address, len, PCI_COMMAND, 0xffff);
+    }
+
     if (!pci_dev->cap.available) {
         /* kill the special capabilities */
         if (address == PCI_COMMAND && len == 4) {