On Wed, 2014-04-02 at 12:16 +1100, Alexey Kardashevskiy wrote:
> On 03/10/2014 04:46 PM, Gavin Shan wrote:
> > The problem is specific to the case of BIST reset issued to IPR
> > adapter on the guest side. The IPR driver calls pci_save_state(),
> > issues BIST reset and then pci_restore_state(). The issued BIST
> > cleans out MSIx table and pci_restore_state() doesn't restore
> > the MSIx table as expected. Eventually, MSIx messages with all
> > zeros are sent and causes EEH error on Power platform.
> >
> > The patch fixes it by writing MSIx message to MSIx table before
> > reenabling the individual interrupts in the following path:
> >
> > qemu/hw/pci/msix.c::msix_table_mmio_write
> > msix_handle_mask_update
> > msix_fire_vector_notifier
> > qemu/hw/misc/vfio.c::vfio_msix_vector_use
> > vfio_msix_vector_do_use
> >
> > IOCTL Command VFIO_DEVICE_SET_IRQS to VFIO-PCI
> > vfio/pci/vfio_pci.c::vfio_pci_ioctl
> > vfio/pci/vfio_pci_intrs.c::vfio_pci_set_irqs_ioctl
> > vfio_pci_set_msi_trigger
> > vfio_msi_set_block
> > vfio_msi_set_vector_signal
> >
> > Reported-by: Wen Xiong <wenxiong@xxxxxxxxxx>
> > Signed-off-by: Gavin Shan <shangw@xxxxxxxxxxxxxxxxxx>
> > ---
> > drivers/vfio/pci/vfio_pci_intrs.c | 11 +++++++++++
> > 1 file changed, 11 insertions(+)
> >
> > diff --git a/drivers/vfio/pci/vfio_pci_intrs.c b/drivers/vfio/pci/vfio_pci_intrs.c
> > index 2103576..83e0638 100644
> > --- a/drivers/vfio/pci/vfio_pci_intrs.c
> > +++ b/drivers/vfio/pci/vfio_pci_intrs.c
> > @@ -17,6 +17,7 @@
> > #include <linux/interrupt.h>
> > #include <linux/eventfd.h>
> > #include <linux/pci.h>
> > +#include <linux/msi.h>
> > #include <linux/file.h>
> > #include <linux/poll.h>
> > #include <linux/vfio.h>
> > @@ -517,6 +518,7 @@ static int vfio_msi_set_vector_signal(struct vfio_pci_device *vdev,
> > struct pci_dev *pdev = vdev->pdev;
> > int irq = msix ? vdev->msix[vector].vector : pdev->irq + vector;
> > char *name = msix ? "vfio-msix" : "vfio-msi";
> > + struct msi_msg msg;
> > struct eventfd_ctx *trigger;
> > int ret;
> >
> > @@ -544,6 +546,15 @@ static int vfio_msi_set_vector_signal(struct vfio_pci_device *vdev,
> > return PTR_ERR(trigger);
> > }
> >
> > + /* We possiblly lose the MSI/MSIx message in some cases, one
> > + * of which is pci_save_state(), BIST reset and pci_restore_state()
> > + * for IPR adapter. The BIST reset cleans out MSIx table and we
> > + * don't have chance to restore it. Here, we have the trick to
> > + * restore it before enabling individual interrupts. For MSI messages,
> > + * it's harmless to write them back.
> > + */
> > + get_cached_msi_msg(irq, &msg);
> > + write_msi_msg(irq, &msg);
> > ret = request_irq(irq, vfio_msihandler, 0,
> > vdev->ctx[vector].name, trigger);
> > if (ret) {
> >
>
>
> This is missing to successfully compile VFIO as modules:
Yep, I noted this in my reply on 3/18. Thanks,
Alex
> diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c
> index 2c10752..80ba2e9 100644
> --- a/drivers/pci/msi.c
> +++ b/drivers/pci/msi.c
> @@ -283,6 +283,7 @@ void get_cached_msi_msg(unsigned int irq, struct
> msi_msg *msg)
>
> __get_cached_msi_msg(entry, msg);
> }
> +EXPORT_SYMBOL_GPL(get_cached_msi_msg);
>
> void __write_msi_msg(struct msi_desc *entry, struct msi_msg *msg)
> {
> @@ -327,6 +328,7 @@ void write_msi_msg(unsigned int irq, struct msi_msg *msg)
>
> __write_msi_msg(entry, msg);
> }
> +EXPORT_SYMBOL_GPL(write_msi_msg);
>
> static void free_msi_irqs(struct pci_dev *dev)
> {
>
>
>
>
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