| Message ID | 20230508154943.30113-1-minipli@grsecurity.net (mailing list archive) |
|---|---|
| Headers | show |
| Series | KVM CR0.WP series backport | expand |
On Mon, May 08, 2023, Mathias Krause wrote: > This is a partial backport of the CR0.WP KVM series[1] to Linux v5.4. It > limits itself to avoid TDP MMU unloading as making CR0.WP a guest owned > bit turned out to be too much of an effort and the partial backport > already being quite effective. > > 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): > > TDP shadow > Linux v5.4.240 8.87s 56.8s > + patches 5.84s 55.4s > > > This kernel version had no module parameter to control the TDP MMU > setting, it's always enabled when EPT / NPT is. Therefore its meaning is > likely what became "legacy" in newer kernels. > > Please consider applying. NAK, same problem as 5.10 and 5.15. Sorry :-(
This is a partial backport of the CR0.WP KVM series[1] to Linux v5.4. It limits itself to avoid TDP MMU unloading as making CR0.WP a guest owned bit turned out to be too much of an effort and the partial backport already being quite effective. 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): TDP shadow Linux v5.4.240 8.87s 56.8s + patches 5.84s 55.4s This kernel version had no module parameter to control the TDP MMU setting, it's always enabled when EPT / NPT is. Therefore its meaning is likely what became "legacy" in newer kernels. 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 (2): 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 Paolo Bonzini (1): KVM: x86/mmu: Avoid indirect call for get_cr3 arch/x86/kvm/mmu.c | 14 +++++++------- arch/x86/kvm/mmu.h | 11 +++++++++++ arch/x86/kvm/paging_tmpl.h | 2 +- arch/x86/kvm/vmx/vmx.c | 4 ++-- arch/x86/kvm/x86.c | 14 +++++++++++++- 5 files changed, 34 insertions(+), 11 deletions(-)