On Sat, Oct 24, 2020 at 08:16:30AM -0600, Alex Williamson wrote:
> On Sat, 24 Oct 2020 19:53:39 +0800
> Yan Zhao <yan.y.z...@intel.com> wrote:
>
> > hi
> > when I migrating VFs, the PCI_COMMAND is not properly saved. and the
> > target side would meet below bug
> > root@tester:~# [ 189.360671] ++++++++++>> reset starts here:
> > iavf_reset_task !!!
> > [ 199.360798] iavf 0000:00:04.0: Reset never finished (0)
> > [ 199.380504] kernel BUG at drivers/pci/msi.c:352!
> > [ 199.382957] invalid opcode: 0000 [#1] SMP PTI
> > [ 199.384855] CPU: 1 PID: 419 Comm: kworker/1:2 Tainted: G OE
> > 5.0.0-13-generic #14-Ubuntu
> > [ 199.388204] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
> > rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
> > [ 199.392401] Workqueue: events iavf_reset_task [iavf]
> > [ 199.393586] RIP: 0010:free_msi_irqs+0x17b/0x1b0
> > [ 199.394659] Code: 84 e1 fe ff ff 45 31 f6 eb 11 41 83 c6 01 44 39 73 14
> > 0f 86 ce fe ff ff 8b 7b 10 44 01 f7 e8 3c 7a ba ff 48 83 78 70 00 74 e0
> > <0f> 0b 49 8d b5 b0 00 00 00 e8 07 27 bb ff e9 cf fe ff ff 48 8b 78
> > [ 199.399056] RSP: 0018:ffffabd1006cfdb8 EFLAGS: 00010282
> > [ 199.400302] RAX: ffff9e336d8a2800 RBX: ffff9e3333b006c0 RCX:
> > 0000000000000000
> > [ 199.402000] RDX: 0000000000000000 RSI: 0000000000000019 RDI:
> > ffffffffbaa68100
> > [ 199.403168] RBP: ffffabd1006cfde8 R08: ffff9e3375000248 R09:
> > ffff9e3375000338
> > [ 199.404343] R10: 0000000000000000 R11: ffffffffbaa68108 R12:
> > ffff9e3374ef12c0
> > [ 199.405526] R13: ffff9e3374ef1000 R14: 0000000000000000 R15:
> > ffff9e3371f2d018
> > [ 199.406702] FS: 0000000000000000(0000) GS:ffff9e3375b00000(0000)
> > knlGS:0000000000000000
> > [ 199.408027] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> > [ 199.408987] CR2: 00000000ffffffff CR3: 0000000033266000 CR4:
> > 00000000000006e0
> > [ 199.410155] DR0: 0000000000000000 DR1: 0000000000000000 DR2:
> > 0000000000000000
> > [ 199.411321] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7:
> > 0000000000000400
> > [ 199.412437] Call Trace:
> > [ 199.412750] pci_disable_msix+0xf3/0x120
> > [ 199.413227] iavf_reset_interrupt_capability.part.40+0x19/0x40 [iavf]
> > [ 199.413998] iavf_reset_task+0x4b3/0x9d0 [iavf]
> > [ 199.414544] process_one_work+0x20f/0x410
> > [ 199.415026] worker_thread+0x34/0x400
> > [ 199.415486] kthread+0x120/0x140
> > [ 199.415876] ? process_one_work+0x410/0x410
> > [ 199.416380] ? __kthread_parkme+0x70/0x70
> > [ 199.416864] ret_from_fork+0x35/0x40
> >
> > I fixed it with below patch.
> >
> >
> > commit ad3efa0eeea7edb352294bfce35b904b8d3c759c
> > Author: Yan Zhao <yan.y.z...@intel.com>
> > Date: Sat Oct 24 19:45:01 2020 +0800
> >
> > msix fix.
> >
> > Signed-off-by: Yan Zhao <yan.y.z...@intel.com>
> >
> > diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
> > index f63f15b553..92f71bf933 100644
> > --- a/hw/vfio/pci.c
> > +++ b/hw/vfio/pci.c
> > @@ -2423,8 +2423,14 @@ const VMStateDescription vmstate_vfio_pci_config = {
> > static void vfio_pci_save_config(VFIODevice *vbasedev, QEMUFile *f)
> > {
> > VFIOPCIDevice *vdev = container_of(vbasedev, VFIOPCIDevice, vbasedev);
> > + PCIDevice *pdev = &vdev->pdev;
> > + uint16_t pci_cmd;
> > +
> > + pci_cmd = pci_default_read_config(pdev, PCI_COMMAND, 2);
> > + qemu_put_be16(f, pci_cmd);
> >
> > vmstate_save_state(f, &vmstate_vfio_pci_config, vdev, NULL);
> > +
> > }
> >
> > static int vfio_pci_load_config(VFIODevice *vbasedev, QEMUFile *f)
> > @@ -2432,6 +2438,10 @@ static int vfio_pci_load_config(VFIODevice
> > *vbasedev, QEMUFile *f)
> > VFIOPCIDevice *vdev = container_of(vbasedev, VFIOPCIDevice, vbasedev);
> > PCIDevice *pdev = &vdev->pdev;
> > int ret;
> > + uint16_t pci_cmd;
> > +
> > + pci_cmd = qemu_get_be16(f);
> > + vfio_pci_write_config(pdev, PCI_COMMAND, pci_cmd, 2);
> >
> > ret = vmstate_load_state(f, &vmstate_vfio_pci_config, vdev, 1);
> > if (ret) {
> >
>
>
> We need to avoid this sort of ad-hoc stuffing random fields into the
> config stream. The command register is already migrated in vconfig, it
> only needs to be written through vfio:
>
> vfio_pci_write_config(pdev, PCI_COMMAND,
> pci_get_word(pdev->config, PCI_COMMAND), 2);
>
yes, it should work. previously we just rely on qemu to save and load
the common fields.
Thanks
Yan
>
>
> > On Fri, Oct 23, 2020 at 04:10:29PM +0530, Kirti Wankhede wrote:
> > > Added functions to save and restore PCI device specific data,
> > > specifically config space of PCI device.
> > >
> > > Signed-off-by: Kirti Wankhede <kwankh...@nvidia.com>
> > > Reviewed-by: Neo Jia <c...@nvidia.com>
> > > ---
> > > hw/vfio/pci.c | 48
> > > +++++++++++++++++++++++++++++++++++++++++++
> > > include/hw/vfio/vfio-common.h | 2 ++
> > > 2 files changed, 50 insertions(+)
> > >
> > > diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
> > > index bffd5bfe3b78..92cc25a5489f 100644
> > > --- a/hw/vfio/pci.c
> > > +++ b/hw/vfio/pci.c
> > > @@ -41,6 +41,7 @@
> > > #include "trace.h"
> > > #include "qapi/error.h"
> > > #include "migration/blocker.h"
> > > +#include "migration/qemu-file.h"
> > >
> > > #define TYPE_VFIO_PCI_NOHOTPLUG "vfio-pci-nohotplug"
> > >
> > > @@ -2401,11 +2402,58 @@ static Object *vfio_pci_get_object(VFIODevice
> > > *vbasedev)
> > > return OBJECT(vdev);
> > > }
> > >
> > > +static bool vfio_msix_present(void *opaque, int version_id)
> > > +{
> > > + PCIDevice *pdev = opaque;
> > > +
> > > + return msix_present(pdev);
> > > +}
> > > +
> > > +const VMStateDescription vmstate_vfio_pci_config = {
> > > + .name = "VFIOPCIDevice",
> > > + .version_id = 1,
> > > + .minimum_version_id = 1,
> > > + .fields = (VMStateField[]) {
> > > + VMSTATE_PCI_DEVICE(pdev, VFIOPCIDevice),
> > > + VMSTATE_MSIX_TEST(pdev, VFIOPCIDevice, vfio_msix_present),
> > > + VMSTATE_END_OF_LIST()
> > > + }
> > > +};
> > > +
> > > +static void vfio_pci_save_config(VFIODevice *vbasedev, QEMUFile *f)
> > > +{
> > > + VFIOPCIDevice *vdev = container_of(vbasedev, VFIOPCIDevice,
> > > vbasedev);
> > > +
> > > + vmstate_save_state(f, &vmstate_vfio_pci_config, vdev, NULL);
> > > +}
> > > +
> > > +static int vfio_pci_load_config(VFIODevice *vbasedev, QEMUFile *f)
> > > +{
> > > + VFIOPCIDevice *vdev = container_of(vbasedev, VFIOPCIDevice,
> > > vbasedev);
> > > + PCIDevice *pdev = &vdev->pdev;
> > > + int ret;
> > > +
> > > + ret = vmstate_load_state(f, &vmstate_vfio_pci_config, vdev, 1);
> > > + if (ret) {
> > > + return ret;
> > > + }
> > > +
> > > + if (msi_enabled(pdev)) {
> > > + vfio_msi_enable(vdev);
> > > + } else if (msix_enabled(pdev)) {
> > > + vfio_msix_enable(vdev);
> > > + }
> > > +
> > > + return ret;
> > > +}
> > > +
> > > static VFIODeviceOps vfio_pci_ops = {
> > > .vfio_compute_needs_reset = vfio_pci_compute_needs_reset,
> > > .vfio_hot_reset_multi = vfio_pci_hot_reset_multi,
> > > .vfio_eoi = vfio_intx_eoi,
> > > .vfio_get_object = vfio_pci_get_object,
> > > + .vfio_save_config = vfio_pci_save_config,
> > > + .vfio_load_config = vfio_pci_load_config,
> > > };
> > >
> > > int vfio_populate_vga(VFIOPCIDevice *vdev, Error **errp)
> > > diff --git a/include/hw/vfio/vfio-common.h b/include/hw/vfio/vfio-common.h
> > > index fe99c36a693a..ba6169cd926e 100644
> > > --- a/include/hw/vfio/vfio-common.h
> > > +++ b/include/hw/vfio/vfio-common.h
> > > @@ -120,6 +120,8 @@ struct VFIODeviceOps {
> > > int (*vfio_hot_reset_multi)(VFIODevice *vdev);
> > > void (*vfio_eoi)(VFIODevice *vdev);
> > > Object *(*vfio_get_object)(VFIODevice *vdev);
> > > + void (*vfio_save_config)(VFIODevice *vdev, QEMUFile *f);
> > > + int (*vfio_load_config)(VFIODevice *vdev, QEMUFile *f);
> > > };
> > >
> > > typedef struct VFIOGroup {
> > > --
> > > 2.7.0
> > >
> >
>
