On Thu, Oct 31, 2024, Sean Christopherson wrote: > On Fri, 06 Sep 2024 18:18:20 -0400, Maxim Levitsky wrote: > > Recently we came up upon a failure where likely the guest writes > > 0xff4547ceb1600000 to MSR_KERNEL_GS_BASE and later on, qemu > > sets this value via KVM_PUT_MSRS, and is rejected by the > > kernel, likely due to not being canonical in 4 level paging. > > > > One of the way to trigger this is to make the guest enter SMM, > > which causes paging to be disabled, which SMM bios re-enables > > but not the whole 5 level. MSR_KERNEL_GS_BASE on the other > > hand continues to contain old value. > > > > [...] > > Applied to kvm-x86 misc, with some massaging (see responsed to individual > patches). Thanks! > > [1/4] KVM: x86: drop x86.h include from cpuid.h > https://github.com/kvm-x86/linux/commit/391bd0c520c1 > [2/4] KVM: x86: implement emul_is_noncanonical_address using is_noncanonical_address > https://github.com/kvm-x86/linux/commit/6c45d62536d0 > [3/4] KVM: x86: model canonical checks more precisely > https://github.com/kvm-x86/linux/commit/1b1336d1d858 > [4/4] KVM: nVMX: fix canonical check of vmcs12 HOST_RIP > https://github.com/kvm-x86/linux/commit/14a95598b6e7 FYI, I rebased misc to v6.12-rc5, as patches in another series had already been taken through the tip tree. New hashes: [1/5] KVM: x86: drop x86.h include from cpuid.h https://github.com/kvm-x86/linux/commit/e52ad1ddd0a3 [2/5] KVM: x86: Route non-canonical checks in emulator through emulate_ops https://github.com/kvm-x86/linux/commit/16ccadefa295 [3/5] KVM: x86: Add X86EMUL_F_MSR and X86EMUL_F_DT_LOAD to aid canonical checks https://github.com/kvm-x86/linux/commit/c534b37b7584 [4/5] KVM: x86: model canonical checks more precisely https://github.com/kvm-x86/linux/commit/9245fd6b8531 [5/5] KVM: nVMX: fix canonical check of vmcs12 HOST_RIP https://github.com/kvm-x86/linux/commit/90a877216e6b
