>-----Original Message-----
>From: Steve Sistare <steven.sist...@oracle.com>
>Subject: [PATCH V1] vfio: fix sub-page bar after cpr
>
>Regions for sub-page BARs are normally mapped here, in response to the
>guest writing to PCI config space:
>
> vfio_pci_write_config()
> pci_default_write_config()
> pci_update_mappings()
> memory_region_add_subregion()
> vfio_sub_page_bar_update_mapping()
> ... vfio_dma_map()
>
>However, after CPR, the guest does not reconfigure the device and the
>code path above is not taken. To fix, in vfio_cpr_pci_post_load, call
>vfio_sub_page_bar_update_mapping for each sub-page BAR with a valid
>address.
>
>Fixes: 7e9f21411302 ("vfio/container: restore DMA vaddr")
>
>Signed-off-by: Steve Sistare <steven.sist...@oracle.com>
Reviewed-by: Zhenzhong Duan <zhenzhong.d...@intel.com>
Just curious what kind of device have sub-page BARs and what's the size of
subpage BAR.
Could you share the output of lspci -s $BDF -v?
Thanks
Zhenzhong
>---
> hw/vfio/pci.h | 1 +
> hw/vfio/cpr.c | 2 ++
> hw/vfio/pci.c | 14 ++++++++++++++
> 3 files changed, 17 insertions(+)
>
>diff --git a/hw/vfio/pci.h b/hw/vfio/pci.h
>index 495fae7..cb1310d 100644
>--- a/hw/vfio/pci.h
>+++ b/hw/vfio/pci.h
>@@ -228,6 +228,7 @@ void vfio_pci_write_config(PCIDevice *pdev,
> uint64_t vfio_vga_read(void *opaque, hwaddr addr, unsigned size);
> void vfio_vga_write(void *opaque, hwaddr addr, uint64_t data, unsigned
>size);
>
>+void vfio_sub_page_bar_update_mappings(VFIOPCIDevice *vdev);
> bool vfio_opt_rom_in_denylist(VFIOPCIDevice *vdev);
> bool vfio_config_quirk_setup(VFIOPCIDevice *vdev, Error **errp);
> void vfio_vga_quirk_setup(VFIOPCIDevice *vdev);
>diff --git a/hw/vfio/cpr.c b/hw/vfio/cpr.c
>index af0f12a..384b56c 100644
>--- a/hw/vfio/cpr.c
>+++ b/hw/vfio/cpr.c
>@@ -116,6 +116,8 @@ static int vfio_cpr_pci_post_load(void *opaque, int
>version_id)
> PCIDevice *pdev = &vdev->pdev;
> int nr_vectors;
>
>+ vfio_sub_page_bar_update_mappings(vdev);
>+
> if (msix_enabled(pdev)) {
> vfio_pci_msix_set_notifiers(vdev);
> nr_vectors = vdev->msix->entries;
>diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
>index 1093b28..9c616bd 100644
>--- a/hw/vfio/pci.c
>+++ b/hw/vfio/pci.c
>@@ -2826,6 +2826,20 @@ static int vfio_pci_load_config(VFIODevice
>*vbasedev, QEMUFile *f)
> return ret;
> }
>
>+void vfio_sub_page_bar_update_mappings(VFIOPCIDevice *vdev)
>+{
>+ PCIDevice *pdev = &vdev->pdev;
>+ int page_size = qemu_real_host_page_size();
>+ int bar;
>+
>+ for (bar = 0; bar < PCI_ROM_SLOT; bar++) {
>+ PCIIORegion *r = &pdev->io_regions[bar];
>+ if (r->addr != PCI_BAR_UNMAPPED && r->size > 0 && r->size <
>page_size) {
>+ vfio_sub_page_bar_update_mapping(pdev, bar);
>+ }
>+ }
>+}
>+
> static VFIODeviceOps vfio_pci_ops = {
> .vfio_compute_needs_reset = vfio_pci_compute_needs_reset,
> .vfio_hot_reset_multi = vfio_pci_hot_reset_multi,
>--
>1.8.3.1
