On 23/08/2015 11:53, Sebastian Schütte wrote: >> What version of SeaBIOS? > 1.8.2 stable, from the Arch repo >> Can you try cherry-picking commit 5492830370171b6a4ede8a3bfba687a8d0f25fa5? > Tried that, but it doesn't seem to make a difference. >> If that fails, can you trace the execution of the VM until the beginning >> of the Linux kernel boot (http://www.linux-kvm.org/page/Tracing) and >> send it compressed to me by email? > I have attached a trace up to the point when the Windows bootloader > kicks in. I could still set up a Linux VM if you think its trace would > be more helpful, though. No, it seems to be in the BIOS. Please try this: diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index 74d825716f4f..f8f69cffecbf 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -882,7 +882,8 @@ static u8 fallback_mtrr_type(int mtrr) case MTRR_TYPE_WRTHROUGH: return MTRR_TYPE_UNCACHABLE; case MTRR_TYPE_WRPROT: - return MTRR_TYPE_UC_MINUS; + /* Assume it's backed by RAM in the host. */ + return MTRR_TYPE_WRBACK; default: BUG(); } @@ -3054,6 +3055,7 @@ static int cr_interception(struct vcpu_svm *svm) if (cr >= 16) { /* mov to cr */ cr -= 16; val = kvm_register_read(&svm->vcpu, reg); + trace_kvm_cr_write(cr, val); switch (cr) { case 0: if (!check_selective_cr0_intercepted(svm, val)) This is a bit of a hack, but it can be enough for a test. For a real patch one would make mtrr2protval bidimensional, accessing it like "return mtrr2protval[is_mmio][mtrr]" in svm_get_mt_mask. Then you can return MTRR_TYPE_UC_MINUS if is_mmio, and MTRR_TYPE_WRBACK if !is_mmio. Paolo -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
