* [Qemu-devel] [PATCH v2] pci-assign: Add MSI affinity support
@ 2013-05-13 20:20 Alex Williamson
2013-05-19 14:00 ` Michael S. Tsirkin
2013-05-22 22:59 ` Anthony Liguori
0 siblings, 2 replies; 5+ messages in thread
From: Alex Williamson @ 2013-05-13 20:20 UTC (permalink / raw)
To: jan.kiszka, mst; +Cc: qemu-devel
To support guest MSI affinity changes update the MSI message any time
the guest writes to the address or data fields.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
---
v2: Don't cache MSIMessage
hw/i386/kvm/pci-assign.c | 18 ++++++++++++++++++
1 file changed, 18 insertions(+)
diff --git a/hw/i386/kvm/pci-assign.c b/hw/i386/kvm/pci-assign.c
index c1e08ec..ff85590 100644
--- a/hw/i386/kvm/pci-assign.c
+++ b/hw/i386/kvm/pci-assign.c
@@ -1026,6 +1026,21 @@ static void assigned_dev_update_msi(PCIDevice *pci_dev)
}
}
+static void assigned_dev_update_msi_msg(PCIDevice *pci_dev)
+{
+ AssignedDevice *assigned_dev = DO_UPCAST(AssignedDevice, dev, pci_dev);
+ uint8_t ctrl_byte = pci_get_byte(pci_dev->config + pci_dev->msi_cap +
+ PCI_MSI_FLAGS);
+
+ if (assigned_dev->assigned_irq_type != ASSIGNED_IRQ_MSI ||
+ !(ctrl_byte & PCI_MSI_FLAGS_ENABLE)) {
+ return;
+ }
+
+ kvm_irqchip_update_msi_route(kvm_state, assigned_dev->msi_virq[0],
+ msi_get_message(pci_dev, 0));
+}
+
static bool assigned_dev_msix_masked(MSIXTableEntry *entry)
{
return (entry->ctrl & cpu_to_le32(0x1)) != 0;
@@ -1201,6 +1216,9 @@ static void assigned_dev_pci_write_config(PCIDevice *pci_dev, uint32_t address,
if (range_covers_byte(address, len,
pci_dev->msi_cap + PCI_MSI_FLAGS)) {
assigned_dev_update_msi(pci_dev);
+ } else if (ranges_overlap(address, len, /* 32bit MSI only */
+ pci_dev->msi_cap + PCI_MSI_ADDRESS_LO, 6)) {
+ assigned_dev_update_msi_msg(pci_dev);
}
}
if (assigned_dev->cap.available & ASSIGNED_DEVICE_CAP_MSIX) {
^ permalink raw reply related [flat|nested] 5+ messages in thread* Re: [Qemu-devel] [PATCH v2] pci-assign: Add MSI affinity support
2013-05-13 20:20 [Qemu-devel] [PATCH v2] pci-assign: Add MSI affinity support Alex Williamson
@ 2013-05-19 14:00 ` Michael S. Tsirkin
2013-05-20 12:51 ` Anthony Liguori
2013-05-22 22:59 ` Anthony Liguori
1 sibling, 1 reply; 5+ messages in thread
From: Michael S. Tsirkin @ 2013-05-19 14:00 UTC (permalink / raw)
To: Alex Williamson; +Cc: jan.kiszka, qemu-devel
On Mon, May 13, 2013 at 02:20:02PM -0600, Alex Williamson wrote:
> To support guest MSI affinity changes update the MSI message any time
> the guest writes to the address or data fields.
>
> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Seems the only way we can fix this for 1.5.
Acked-by: Michael S. Tsirkin <mst@redhat.com>
> ---
>
> v2: Don't cache MSIMessage
>
> hw/i386/kvm/pci-assign.c | 18 ++++++++++++++++++
> 1 file changed, 18 insertions(+)
>
> diff --git a/hw/i386/kvm/pci-assign.c b/hw/i386/kvm/pci-assign.c
> index c1e08ec..ff85590 100644
> --- a/hw/i386/kvm/pci-assign.c
> +++ b/hw/i386/kvm/pci-assign.c
> @@ -1026,6 +1026,21 @@ static void assigned_dev_update_msi(PCIDevice *pci_dev)
> }
> }
>
> +static void assigned_dev_update_msi_msg(PCIDevice *pci_dev)
> +{
> + AssignedDevice *assigned_dev = DO_UPCAST(AssignedDevice, dev, pci_dev);
> + uint8_t ctrl_byte = pci_get_byte(pci_dev->config + pci_dev->msi_cap +
> + PCI_MSI_FLAGS);
> +
> + if (assigned_dev->assigned_irq_type != ASSIGNED_IRQ_MSI ||
> + !(ctrl_byte & PCI_MSI_FLAGS_ENABLE)) {
> + return;
> + }
> +
> + kvm_irqchip_update_msi_route(kvm_state, assigned_dev->msi_virq[0],
> + msi_get_message(pci_dev, 0));
> +}
> +
> static bool assigned_dev_msix_masked(MSIXTableEntry *entry)
> {
> return (entry->ctrl & cpu_to_le32(0x1)) != 0;
> @@ -1201,6 +1216,9 @@ static void assigned_dev_pci_write_config(PCIDevice *pci_dev, uint32_t address,
> if (range_covers_byte(address, len,
> pci_dev->msi_cap + PCI_MSI_FLAGS)) {
> assigned_dev_update_msi(pci_dev);
> + } else if (ranges_overlap(address, len, /* 32bit MSI only */
> + pci_dev->msi_cap + PCI_MSI_ADDRESS_LO, 6)) {
> + assigned_dev_update_msi_msg(pci_dev);
> }
> }
> if (assigned_dev->cap.available & ASSIGNED_DEVICE_CAP_MSIX) {
^ permalink raw reply [flat|nested] 5+ messages in thread* Re: [Qemu-devel] [PATCH v2] pci-assign: Add MSI affinity support
2013-05-19 14:00 ` Michael S. Tsirkin
@ 2013-05-20 12:51 ` Anthony Liguori
2013-05-20 13:15 ` Michael S. Tsirkin
0 siblings, 1 reply; 5+ messages in thread
From: Anthony Liguori @ 2013-05-20 12:51 UTC (permalink / raw)
To: Michael S. Tsirkin, Alex Williamson; +Cc: jan.kiszka, qemu-devel
"Michael S. Tsirkin" <mst@redhat.com> writes:
> On Mon, May 13, 2013 at 02:20:02PM -0600, Alex Williamson wrote:
>> To support guest MSI affinity changes update the MSI message any time
>> the guest writes to the address or data fields.
>>
>> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
>
> Seems the only way we can fix this for 1.5.
>
> Acked-by: Michael S. Tsirkin <mst@redhat.com>
Is this a bug or a feature? Can someone describe the scenario in which
the bug occurs?
Regards,
Anthony Liguori
>
>> ---
>>
>> v2: Don't cache MSIMessage
>>
>> hw/i386/kvm/pci-assign.c | 18 ++++++++++++++++++
>> 1 file changed, 18 insertions(+)
>>
>> diff --git a/hw/i386/kvm/pci-assign.c b/hw/i386/kvm/pci-assign.c
>> index c1e08ec..ff85590 100644
>> --- a/hw/i386/kvm/pci-assign.c
>> +++ b/hw/i386/kvm/pci-assign.c
>> @@ -1026,6 +1026,21 @@ static void assigned_dev_update_msi(PCIDevice *pci_dev)
>> }
>> }
>>
>> +static void assigned_dev_update_msi_msg(PCIDevice *pci_dev)
>> +{
>> + AssignedDevice *assigned_dev = DO_UPCAST(AssignedDevice, dev, pci_dev);
>> + uint8_t ctrl_byte = pci_get_byte(pci_dev->config + pci_dev->msi_cap +
>> + PCI_MSI_FLAGS);
>> +
>> + if (assigned_dev->assigned_irq_type != ASSIGNED_IRQ_MSI ||
>> + !(ctrl_byte & PCI_MSI_FLAGS_ENABLE)) {
>> + return;
>> + }
>> +
>> + kvm_irqchip_update_msi_route(kvm_state, assigned_dev->msi_virq[0],
>> + msi_get_message(pci_dev, 0));
>> +}
>> +
>> static bool assigned_dev_msix_masked(MSIXTableEntry *entry)
>> {
>> return (entry->ctrl & cpu_to_le32(0x1)) != 0;
>> @@ -1201,6 +1216,9 @@ static void assigned_dev_pci_write_config(PCIDevice *pci_dev, uint32_t address,
>> if (range_covers_byte(address, len,
>> pci_dev->msi_cap + PCI_MSI_FLAGS)) {
>> assigned_dev_update_msi(pci_dev);
>> + } else if (ranges_overlap(address, len, /* 32bit MSI only */
>> + pci_dev->msi_cap + PCI_MSI_ADDRESS_LO, 6)) {
>> + assigned_dev_update_msi_msg(pci_dev);
>> }
>> }
>> if (assigned_dev->cap.available & ASSIGNED_DEVICE_CAP_MSIX) {
^ permalink raw reply [flat|nested] 5+ messages in thread* Re: [Qemu-devel] [PATCH v2] pci-assign: Add MSI affinity support
2013-05-20 12:51 ` Anthony Liguori
@ 2013-05-20 13:15 ` Michael S. Tsirkin
0 siblings, 0 replies; 5+ messages in thread
From: Michael S. Tsirkin @ 2013-05-20 13:15 UTC (permalink / raw)
To: Anthony Liguori; +Cc: jan.kiszka, Alex Williamson, qemu-devel
On Mon, May 20, 2013 at 07:51:40AM -0500, Anthony Liguori wrote:
> "Michael S. Tsirkin" <mst@redhat.com> writes:
>
> > On Mon, May 13, 2013 at 02:20:02PM -0600, Alex Williamson wrote:
> >> To support guest MSI affinity changes update the MSI message any time
> >> the guest writes to the address or data fields.
> >>
> >> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
> >
> > Seems the only way we can fix this for 1.5.
> >
> > Acked-by: Michael S. Tsirkin <mst@redhat.com>
>
> Is this a bug or a feature? Can someone describe the scenario in which
> the bug occurs?
>
> Regards,
>
> Anthony Liguori
It's a bug. Here's how it occurs w.g. with a linux guest:
- guest kernel enables MSI, interrupts are sent to CPU0
- irqbalance runs in guest and moves MSI to CPU1
- guest kernel updates MSI register with new data
without this patch interrupts keep getting sent to CPU0
in violation of the spec.
> >
> >> ---
> >>
> >> v2: Don't cache MSIMessage
> >>
> >> hw/i386/kvm/pci-assign.c | 18 ++++++++++++++++++
> >> 1 file changed, 18 insertions(+)
> >>
> >> diff --git a/hw/i386/kvm/pci-assign.c b/hw/i386/kvm/pci-assign.c
> >> index c1e08ec..ff85590 100644
> >> --- a/hw/i386/kvm/pci-assign.c
> >> +++ b/hw/i386/kvm/pci-assign.c
> >> @@ -1026,6 +1026,21 @@ static void assigned_dev_update_msi(PCIDevice *pci_dev)
> >> }
> >> }
> >>
> >> +static void assigned_dev_update_msi_msg(PCIDevice *pci_dev)
> >> +{
> >> + AssignedDevice *assigned_dev = DO_UPCAST(AssignedDevice, dev, pci_dev);
> >> + uint8_t ctrl_byte = pci_get_byte(pci_dev->config + pci_dev->msi_cap +
> >> + PCI_MSI_FLAGS);
> >> +
> >> + if (assigned_dev->assigned_irq_type != ASSIGNED_IRQ_MSI ||
> >> + !(ctrl_byte & PCI_MSI_FLAGS_ENABLE)) {
> >> + return;
> >> + }
> >> +
> >> + kvm_irqchip_update_msi_route(kvm_state, assigned_dev->msi_virq[0],
> >> + msi_get_message(pci_dev, 0));
> >> +}
> >> +
> >> static bool assigned_dev_msix_masked(MSIXTableEntry *entry)
> >> {
> >> return (entry->ctrl & cpu_to_le32(0x1)) != 0;
> >> @@ -1201,6 +1216,9 @@ static void assigned_dev_pci_write_config(PCIDevice *pci_dev, uint32_t address,
> >> if (range_covers_byte(address, len,
> >> pci_dev->msi_cap + PCI_MSI_FLAGS)) {
> >> assigned_dev_update_msi(pci_dev);
> >> + } else if (ranges_overlap(address, len, /* 32bit MSI only */
> >> + pci_dev->msi_cap + PCI_MSI_ADDRESS_LO, 6)) {
> >> + assigned_dev_update_msi_msg(pci_dev);
> >> }
> >> }
> >> if (assigned_dev->cap.available & ASSIGNED_DEVICE_CAP_MSIX) {
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [Qemu-devel] [PATCH v2] pci-assign: Add MSI affinity support
2013-05-13 20:20 [Qemu-devel] [PATCH v2] pci-assign: Add MSI affinity support Alex Williamson
2013-05-19 14:00 ` Michael S. Tsirkin
@ 2013-05-22 22:59 ` Anthony Liguori
1 sibling, 0 replies; 5+ messages in thread
From: Anthony Liguori @ 2013-05-22 22:59 UTC (permalink / raw)
To: Alex Williamson, jan.kiszka, mst; +Cc: qemu-devel
Applied. Thanks.
Regards,
Anthony Liguori
^ permalink raw reply [flat|nested] 5+ messages in thread
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2013-05-13 20:20 [Qemu-devel] [PATCH v2] pci-assign: Add MSI affinity support Alex Williamson
2013-05-19 14:00 ` Michael S. Tsirkin
2013-05-20 12:51 ` Anthony Liguori
2013-05-20 13:15 ` Michael S. Tsirkin
2013-05-22 22:59 ` Anthony Liguori
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