| Message ID | 1333455707-3534-1-git-send-email-hdegoede@redhat.com |
|---|---|
| State | New |
| Headers | show |
On Tue, Apr 03, 2012 at 02:21:47PM +0200, Hans de Goede wrote: > frindex is a 14 bits counter, so bits 31-14 should always be 0, and > after the commit titled "usb-ehci: frindex always is a 14 bits counter" > we rely on frindex always being a multiple of 8. I've not seen this in > practice, but theoretically a guest can write a value >= 0x4000 or a value > which is not a multiple of 8 value to frindex, this patch ensures that > things will still work when that happens. Acked-by: Alon Levy <alevy@redhat.com> > > Signed-off-by: Hans de Goede <hdegoede@redhat.com> > --- > hw/usb/hcd-ehci.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/hw/usb/hcd-ehci.c b/hw/usb/hcd-ehci.c > index 64b58e3..8865b4e 100644 > --- a/hw/usb/hcd-ehci.c > +++ b/hw/usb/hcd-ehci.c > @@ -1102,6 +1102,10 @@ static void ehci_mem_writel(void *ptr, target_phys_addr_t addr, uint32_t val) > val &= USBINTR_MASK; > break; > > + case FRINDEX: > + val &= 0x00003ff8; /* frindex is 14bits and always a multiple of 8 */ > + break; > + > case CONFIGFLAG: > val &= 0x1; > if (val) { > -- > 1.7.9.3 > >
On Tue, Apr 03, 2012 at 04:16:02PM +0300, Alon Levy wrote: > On Tue, Apr 03, 2012 at 02:21:47PM +0200, Hans de Goede wrote: > > frindex is a 14 bits counter, so bits 31-14 should always be 0, and > > after the commit titled "usb-ehci: frindex always is a 14 bits counter" > > we rely on frindex always being a multiple of 8. I've not seen this in > > practice, but theoretically a guest can write a value >= 0x4000 or a value > > which is not a multiple of 8 value to frindex, this patch ensures that > > things will still work when that happens. > > Acked-by: Alon Levy <alevy@redhat.com> I meant: Reviewed-by: Alon Levy <alevy@redhat.com> > > > > > Signed-off-by: Hans de Goede <hdegoede@redhat.com> > > --- > > hw/usb/hcd-ehci.c | 4 ++++ > > 1 file changed, 4 insertions(+) > > > > diff --git a/hw/usb/hcd-ehci.c b/hw/usb/hcd-ehci.c > > index 64b58e3..8865b4e 100644 > > --- a/hw/usb/hcd-ehci.c > > +++ b/hw/usb/hcd-ehci.c > > @@ -1102,6 +1102,10 @@ static void ehci_mem_writel(void *ptr, target_phys_addr_t addr, uint32_t val) > > val &= USBINTR_MASK; > > break; > > > > + case FRINDEX: > > + val &= 0x00003ff8; /* frindex is 14bits and always a multiple of 8 */ > > + break; > > + > > case CONFIGFLAG: > > val &= 0x1; > > if (val) { > > -- > > 1.7.9.3 > > > > >
On 04/03/12 14:21, Hans de Goede wrote: > frindex is a 14 bits counter, so bits 31-14 should always be 0, and > after the commit titled "usb-ehci: frindex always is a 14 bits counter" > we rely on frindex always being a multiple of 8. I've not seen this in > practice, but theoretically a guest can write a value >= 0x4000 or a value > which is not a multiple of 8 value to frindex, this patch ensures that > things will still work when that happens. Patch added to usb patch queue. thanks, Gerd
diff --git a/hw/usb/hcd-ehci.c b/hw/usb/hcd-ehci.c index 64b58e3..8865b4e 100644 --- a/hw/usb/hcd-ehci.c +++ b/hw/usb/hcd-ehci.c @@ -1102,6 +1102,10 @@ static void ehci_mem_writel(void *ptr, target_phys_addr_t addr, uint32_t val) val &= USBINTR_MASK; break; + case FRINDEX: + val &= 0x00003ff8; /* frindex is 14bits and always a multiple of 8 */ + break; + case CONFIGFLAG: val &= 0x1; if (val) {
frindex is a 14 bits counter, so bits 31-14 should always be 0, and after the commit titled "usb-ehci: frindex always is a 14 bits counter" we rely on frindex always being a multiple of 8. I've not seen this in practice, but theoretically a guest can write a value >= 0x4000 or a value which is not a multiple of 8 value to frindex, this patch ensures that things will still work when that happens. Signed-off-by: Hans de Goede <hdegoede@redhat.com> --- hw/usb/hcd-ehci.c | 4 ++++ 1 file changed, 4 insertions(+)