From 14d91c353e19b7085fdbb7b2dcc43f3355665670 Mon Sep 17 00:00:00 2001 From: Marcel Apfelbaum Date: Thu, 11 Jan 2018 22:15:12 +0200 Subject: [PATCH] pci: fix 'io hints' capability for RedHat PCI bridges Commit ec6cb17f (pci: enable RedHat PCI bridges to reserve additional resources on PCI init) added a new vendor specific PCI capability for RedHat PCI bridges allowing them to reserve additional buses and/or IO/MEM space. When adding the IO hints PCI capability to the pcie-root-port without specifying a value for bus reservation, the subordinate bus computation is wrong and the guest kernel gets messed up. Fix it by returning to prev code if the value for bus reservation is not set. Removed also a wrong debug print "PCI: invalid QEMU resource reserve cap offset" which appears if the 'IO hints' capability is not present. Acked-by: Michael S. Tsirkin Signed-off-by: Marcel Apfelbaum --- src/fw/pciinit.c | 14 +++++--------- 1 file changed, 5 insertions(+), 9 deletions(-) diff --git a/src/fw/pciinit.c b/src/fw/pciinit.c index 7f0e439..3a2f747 100644 --- a/src/fw/pciinit.c +++ b/src/fw/pciinit.c @@ -540,8 +540,6 @@ static u8 pci_find_resource_reserve_capability(u16 bdf) dprintf(1, "PCI: QEMU resource reserve cap length %d is invalid\n", cap_len); } - } else { - dprintf(1, "PCI: invalid QEMU resource reserve cap offset\n"); } return cap; } else { @@ -619,13 +617,11 @@ pci_bios_init_bus_rec(int bus, u8 *pci_bus) res_bus); res_bus = 0; } - } - if (secbus + res_bus > *pci_bus) { - dprintf(1, "PCI: QEMU resource reserve cap: bus = %u\n", - res_bus); - res_bus = secbus + res_bus; - } else { - res_bus = *pci_bus; + if (secbus + res_bus > *pci_bus) { + dprintf(1, "PCI: QEMU resource reserve cap: bus = %u\n", + res_bus); + res_bus = secbus + res_bus; + } } } dprintf(1, "PCI: subordinate bus = 0x%x -> 0x%x\n", -- 2.39.5