diff mbox series

[v28,03/17] vfio: Add save and load functions for VFIO PCI devices

Message ID 1603449643-12851-4-git-send-email-kwankhede@nvidia.com
State New
Headers show
Series Add migration support for VFIO devices | expand

Commit Message

Kirti Wankhede Oct. 23, 2020, 10:40 a.m. UTC 
Added functions to save and restore PCI device specific data,
specifically config space of PCI device.

Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Reviewed-by: Neo Jia <cjia@nvidia.com>
---
 hw/vfio/pci.c                 | 48 +++++++++++++++++++++++++++++++++++++++++++
 include/hw/vfio/vfio-common.h |  2 ++
 2 files changed, 50 insertions(+)

Comments

Yan Zhao Oct. 24, 2020, 11:53 a.m. UTC | #1 
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.zhao@intel.com>
Date:   Sat Oct 24 19:45:01 2020 +0800

    msix fix.
    
    Signed-off-by: Yan Zhao <yan.y.zhao@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) {


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 <kwankhede@nvidia.com>
> Reviewed-by: Neo Jia <cjia@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
>
Alex Williamson Oct. 24, 2020, 2:16 p.m. UTC | #2 
On Sat, 24 Oct 2020 19:53:39 +0800
Yan Zhao <yan.y.zhao@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.zhao@intel.com>
> Date:   Sat Oct 24 19:45:01 2020 +0800
> 
>     msix fix.
>     
>     Signed-off-by: Yan Zhao <yan.y.zhao@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);

Thanks,
Alex


> 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 <kwankhede@nvidia.com>
> > Reviewed-by: Neo Jia <cjia@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
> >   
>
Kirti Wankhede Oct. 24, 2020, 7:48 p.m. UTC | #3 
On 10/24/2020 7:46 PM, Alex Williamson wrote:
> On Sat, 24 Oct 2020 19:53:39 +0800
> Yan Zhao <yan.y.zhao@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 verified MSIx with SRIOV VF, and I don't see this issue at my end.

>> I fixed it with below patch.
>>
>>
>> commit ad3efa0eeea7edb352294bfce35b904b8d3c759c
>> Author: Yan Zhao <yan.y.zhao@intel.com>
>> Date:   Sat Oct 24 19:45:01 2020 +0800
>>
>>      msix fix.
>>      
>>      Signed-off-by: Yan Zhao <yan.y.zhao@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);
> 

I verified at my end again.
pci command value (using pci_default_read_config()) before 
vmstate_save_state() is 0x507 and at destination after 
vmstate_load_state() is also 0x507 - with pci_default_read_config() and 
the cached config space value using pci_get_word() - both are 0x507.
VM restores successfully.

Yan, can you share pci command values before and after as above? what 
exactly is missing?

Thanks,
Kirti

> Thanks,
> Alex
> 
> 
>> 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 <kwankhede@nvidia.com>
>>> Reviewed-by: Neo Jia <cjia@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
>>>    
>>
>
Alex Williamson Oct. 24, 2020, 8:23 p.m. UTC | #4 
On Sun, 25 Oct 2020 01:18:37 +0530
Kirti Wankhede <kwankhede@nvidia.com> wrote:

> On 10/24/2020 7:46 PM, Alex Williamson wrote:
> > On Sat, 24 Oct 2020 19:53:39 +0800
> > Yan Zhao <yan.y.zhao@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 verified MSIx with SRIOV VF, and I don't see this issue at my end.
> 
> >> I fixed it with below patch.
> >>
> >>
> >> commit ad3efa0eeea7edb352294bfce35b904b8d3c759c
> >> Author: Yan Zhao <yan.y.zhao@intel.com>
> >> Date:   Sat Oct 24 19:45:01 2020 +0800
> >>
> >>      msix fix.
> >>      
> >>      Signed-off-by: Yan Zhao <yan.y.zhao@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);
> >   
> 
> I verified at my end again.
> pci command value (using pci_default_read_config()) before 
> vmstate_save_state() is 0x507 and at destination after 
> vmstate_load_state() is also 0x507 - with pci_default_read_config() and 
> the cached config space value using pci_get_word() - both are 0x507.
> VM restores successfully.
> 
> Yan, can you share pci command values before and after as above? what 
> exactly is missing?

pci_default_read_config() or pci_get_word() only read from virtual
config space, something needs to write it through to the device on the
target, much like we're doing to enable msi and msix.  Thanks,

Alex


> >> 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 <kwankhede@nvidia.com>
> >>> Reviewed-by: Neo Jia <cjia@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
> >>>      
> >>  
> >   
>
Yan Zhao Oct. 25, 2020, 4:26 a.m. UTC | #5 
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.zhao@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.zhao@intel.com>
> > Date:   Sat Oct 24 19:45:01 2020 +0800
> > 
> >     msix fix.
> >     
> >     Signed-off-by: Yan Zhao <yan.y.zhao@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 <kwankhede@nvidia.com>
> > > Reviewed-by: Neo Jia <cjia@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
> > >   
> > 
>
diff mbox series

Patch

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 {