This is a backport of the CR0.WP KVM series[1] to Linux v6.2. All commits applied either clean or with only minor changes needed to account for missing prerequisite patches, e.g. the lack of a kvm_is_cr0_bit_set() helper for patch 5 or the slightly different surrounding context in patch 4 (__always_inline vs. plain inline for to_kvm_vmx()).
I used 'ssdd 10 50000' from rt-tests[2] as a micro-benchmark, running on a grsecurity L1 VM. Below table shows the results (runtime in seconds, lower is better):
legacy TDP shadow Linux v6.2.10 7.61s 7.98s 68.6s + patches 3.37s 3.41s 70.2s
The KVM unit test suite showed no regressions.
Please consider applying.
Thanks, Mathias
[1] https://lore.kernel.org/kvm/20230322013731.102955-1-minipli@grsecurity.net/ [2] https://git.kernel.org/pub/scm/utils/rt-tests/rt-tests.git
Mathias Krause (3): KVM: x86: Do not unload MMU roots when only toggling CR0.WP with TDP enabled KVM: x86: Make use of kvm_read_cr*_bits() when testing bits KVM: VMX: Make CR0.WP a guest owned bit
Paolo Bonzini (1): KVM: x86/mmu: Avoid indirect call for get_cr3
Sean Christopherson (1): KVM: x86/mmu: Refresh CR0.WP prior to checking for emulated permission faults
arch/x86/kvm/kvm_cache_regs.h | 2 +- arch/x86/kvm/mmu.h | 26 ++++++++++++++++++- arch/x86/kvm/mmu/mmu.c | 46 ++++++++++++++++++++++++++-------- arch/x86/kvm/mmu/paging_tmpl.h | 2 +- arch/x86/kvm/pmu.c | 4 +-- arch/x86/kvm/vmx/nested.c | 4 +-- arch/x86/kvm/vmx/vmx.c | 6 ++--- arch/x86/kvm/vmx/vmx.h | 18 +++++++++++++ arch/x86/kvm/x86.c | 12 +++++++++ 9 files changed, 99 insertions(+), 21 deletions(-)