On 27.03.23 10:33, Xiaoyao Li wrote: > On 3/22/2023 9:37 AM, Mathias Krause wrote: >> Guests like grsecurity that make heavy use of CR0.WP to implement kernel >> level W^X will suffer from the implied VMEXITs. >> >> With EPT there is no need to intercept a guest change of CR0.WP, so >> simply make it a guest owned bit if we can do so. > > I'm interested in the performance gain. Do you have data like Patch 2? It's mentioned in the cover letter[1], quoted below: [1] https://lore.kernel.org/kvm/20230322013731.102955-1-minipli@xxxxxxxxxxxxxx/ : I used 'ssdd 10 50000' from rt-tests[5] as a micro-benchmark, running on a : grsecurity L1 VM. Below table shows the results (runtime in seconds, lower : is better): : : legacy TDP shadow : kvm-x86/next@d8708b 8.43s 9.45s 70.3s : + patches 1-3 5.39s 5.63s 70.2s : + patches 4-6 3.51s 3.47s 67.8s Thanks, Mathias
