From a52a4c471703e995ceb06f6157d70747823e8a0d Mon Sep 17 00:00:00 2001 From: Ido Yariv Date: Mon, 31 Oct 2016 09:53:04 -0600 Subject: [PATCH] vfio/pci: fix out-of-sync BAR information on reset When a PCI device is reset, pci_do_device_reset resets all BAR addresses in the relevant PCIDevice's config buffer. The VFIO configuration space stays untouched, so the guest OS may choose to skip restoring the BAR addresses as they would seem intact. The PCI device may be left non-operational. One example of such a scenario is when the guest exits S3. Fix this by resetting the BAR addresses in the VFIO configuration space as well. Signed-off-by: Ido Yariv Signed-off-by: Alex Williamson --- hw/vfio/pci.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c index 65d30fdef9..b399742058 100644 --- a/hw/vfio/pci.c +++ b/hw/vfio/pci.c @@ -1922,11 +1922,23 @@ static void vfio_pci_pre_reset(VFIOPCIDevice *vdev) static void vfio_pci_post_reset(VFIOPCIDevice *vdev) { Error *err = NULL; + int nr; vfio_intx_enable(vdev, &err); if (err) { error_reportf_err(err, ERR_PREFIX, vdev->vbasedev.name); } + + for (nr = 0; nr < PCI_NUM_REGIONS - 1; ++nr) { + off_t addr = vdev->config_offset + PCI_BASE_ADDRESS_0 + (4 * nr); + uint32_t val = 0; + uint32_t len = sizeof(val); + + if (pwrite(vdev->vbasedev.fd, &val, len, addr) != len) { + error_report("%s(%s) reset bar %d failed: %m", __func__, + vdev->vbasedev.name, nr); + } + } } static bool vfio_pci_host_match(PCIHostDeviceAddress *addr, const char *name) -- 2.39.5