diff options
| -rw-r--r-- | src/fw/pciinit.c | 15 |
1 files changed, 10 insertions, 5 deletions
diff --git a/src/fw/pciinit.c b/src/fw/pciinit.c index bb44dc2..b3e359d 100644 --- a/src/fw/pciinit.c +++ b/src/fw/pciinit.c @@ -1189,11 +1189,16 @@ pci_setup(void) if (CPUPhysBits) { pci_mem64_top = 1LL << CPUPhysBits; - if (CPUPhysBits > 46) { - // Old linux kernels have trouble dealing with more than 46 - // phys-bits, so avoid that for now. Seems to be a bug in the - // virtio-pci driver. Reported: centos-7, ubuntu-18.04 - pci_mem64_top = 1LL << 46; + if (CPUPhysBits > 44) { + // Old linux kernels have trouble dealing with more than 44 (i386 + // kernels) or 46 (x86_64 kernels) phys-bits. Seems to be a bug in + // the virtio-pci driver. + // Reported: centos-7, ubuntu-18.04 + // Limit the used address space to mitigate the bug, except we are + // running in a huge guest with more than 1TB of memory installed. + if (RamSizeOver4G < (1LL << 40)) { + pci_mem64_top = 1LL << 44; + } } } |