On Mon, Dec 13, 2010 at 01:04:23PM -0700, Alex Williamson wrote: > On Mon, 2010-11-08 at 13:22 +0200, Michael S. Tsirkin wrote: > > On Mon, Oct 04, 2010 at 03:53:11PM -0600, Alex Williamson wrote: > > > pcibus_dev_print() was erroneously retrieving the device bus > > > number from the secondary bus number offset of the device > > > instead of the bridge above the device. This ends of landing > > > in the 2nd byte of the 3rd BAR for devices, which thankfully > > > is usually zero. pcibus_get_dev_path() copied this code, > > > inheriting the same bug. pcibus_get_dev_path() is used for > > > ramblock naming, so changing it can effect migration. However, > > > I've only seen this byte be non-zero for an assigned device, > > > which can't migrate anyway, so hopefully we won't run into > > > any issues. > > > > > > Signed-off-by: Alex Williamson <alex.william...@redhat.com> > > > > Good catch. Applied. > > Um... submitted vs applied: > > PCI: Bus number from the bridge, not the device > > @@ -6,20 +8,28 @@ > number from the secondary bus number offset of the device > instead of the bridge above the device. This ends of landing > in the 2nd byte of the 3rd BAR for devices, which thankfully > - is usually zero. pcibus_get_dev_path() copied this code, > + is usually zero. > + > + Note: pcibus_get_dev_path() copied this code, > inheriting the same bug. pcibus_get_dev_path() is used for > ramblock naming, so changing it can effect migration. However, > I've only seen this byte be non-zero for an assigned device, > which can't migrate anyway, so hopefully we won't run into > any issues. > > + This patch does not touch pcibus_get_dev_path, as > + bus number is guest assigned for nested buses, > + so using it for migration is broken anyway. > + Fix it properly later. > + > Signed-off-by: Alex Williamson <alex.william...@redhat.com> > + Signed-off-by: Michael S. Tsirkin <m...@redhat.com> > > diff --git a/hw/pci.c b/hw/pci.c > -index 6d0934d..15416dd 100644 > +index 962886e..8f6fcf8 100644 > --- a/hw/pci.c > +++ b/hw/pci.c > -@@ -1940,8 +1940,7 @@ static void pcibus_dev_print(Monitor *mon, DeviceState > *dev, int indent) > +@@ -1806,8 +1806,7 @@ static void pcibus_dev_print(Monitor *mon, DeviceState > *dev, int indent) > > monitor_printf(mon, "%*sclass %s, addr %02x:%02x.%x, " > "pci id %04x:%04x (sub %04x:%04x)\n", > @@ -29,14 +39,3 @@ > PCI_SLOT(d->devfn), PCI_FUNC(d->devfn), > pci_get_word(d->config + PCI_VENDOR_ID), > pci_get_word(d->config + PCI_DEVICE_ID), > -@@ -1965,7 +1964,7 @@ static char *pcibus_get_dev_path(DeviceState *dev) > - char path[16]; > - > - snprintf(path, sizeof(path), "%04x:%02x:%02x.%x", > -- pci_find_domain(d->bus), d->config[PCI_SECONDARY_BUS], > -+ pci_find_domain(d->bus), pci_bus_num(d->bus), > - PCI_SLOT(d->devfn), PCI_FUNC(d->devfn)); > - > - return strdup(path); > - > - > > So the chunk that fixed the part that I was actually interested in got > dropped even though the existing code is clearly wrong. Yes, we still > have issues with nested bridges (not that we have many of those), but > until the "Fix it properly later" part comes along, can we please > include the obvious bug fix? Thanks, > > Alex
We can stick 0 in there - would that help? I would much rather not create a version where we put the bus number there. -- MST
