From: Michael S. Tsirkin Date: Mon, 28 Apr 2014 14:02:21 +0000 (+0300) Subject: pci-assign: limit # of msix vectors X-Git-Tag: qemu-xen-4.5.0-rc1^2~76 X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=96e7f7a911077ac76c4b2ac1e31e0aeaa1fb2901;p=qemu-upstream-4.5-testing.git pci-assign: limit # of msix vectors KVM only supports MSIX table size up to 256 vectors, but some assigned devices support more vectors, at the moment attempts to assign them fail with EINVAL. Tweak the MSIX capability exposed to guest to limit table size to a supported value. Signed-off-by: Michael S. Tsirkin Tested-by: Gonglei Cc: qemu-stable@nongnu.org Acked-by: Alex Williamson Signed-off-by: Paolo Bonzini (cherry picked from commit 639973a4740f38789057744b550df3a175bc49ad) Signed-off-by: Michael Roth --- diff --git a/hw/i386/kvm/pci-assign.c b/hw/i386/kvm/pci-assign.c index a825871d8..76aa86e7b 100644 --- a/hw/i386/kvm/pci-assign.c +++ b/hw/i386/kvm/pci-assign.c @@ -1258,6 +1258,7 @@ static int assigned_device_pci_cap_init(PCIDevice *pci_dev) if (pos != 0 && kvm_device_msix_supported(kvm_state)) { int bar_nr; uint32_t msix_table_entry; + uint16_t msix_max; if (!check_irqchip_in_kernel()) { return -ENOTSUP; @@ -1269,9 +1270,10 @@ static int assigned_device_pci_cap_init(PCIDevice *pci_dev) } pci_dev->msix_cap = pos; - pci_set_word(pci_dev->config + pos + PCI_MSIX_FLAGS, - pci_get_word(pci_dev->config + pos + PCI_MSIX_FLAGS) & - PCI_MSIX_FLAGS_QSIZE); + msix_max = (pci_get_word(pci_dev->config + pos + PCI_MSIX_FLAGS) & + PCI_MSIX_FLAGS_QSIZE) + 1; + msix_max = MIN(msix_max, KVM_MAX_MSIX_PER_DEV); + pci_set_word(pci_dev->config + pos + PCI_MSIX_FLAGS, msix_max - 1); /* Only enable and function mask bits are writable */ pci_set_word(pci_dev->wmask + pos + PCI_MSIX_FLAGS, @@ -1281,9 +1283,7 @@ static int assigned_device_pci_cap_init(PCIDevice *pci_dev) bar_nr = msix_table_entry & PCI_MSIX_FLAGS_BIRMASK; msix_table_entry &= ~PCI_MSIX_FLAGS_BIRMASK; dev->msix_table_addr = pci_region[bar_nr].base_addr + msix_table_entry; - dev->msix_max = pci_get_word(pci_dev->config + pos + PCI_MSIX_FLAGS); - dev->msix_max &= PCI_MSIX_FLAGS_QSIZE; - dev->msix_max += 1; + dev->msix_max = msix_max; } /* Minimal PM support, nothing writable, device appears to NAK changes */