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| author | Sean Christopherson <seanjc@google.com> | 2021-02-25 12:47:44 -0800 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2021-03-15 04:43:50 -0400 |
| commit | 613a3f3797528be489d280c35c4f6ebfcbe77e9e (patch) | |
| tree | fefa0592baebdefbdaa9e5cab789e11ec67c4ef4 /tools/perf/scripts/python/event_analyzing_sample.py | |
| parent | 5fc3424f8b854584f8f6fb6ea03f1419487fdc96 (diff) | |
| download | linux-613a3f3797528be489d280c35c4f6ebfcbe77e9e.tar.gz linux-613a3f3797528be489d280c35c4f6ebfcbe77e9e.zip | |
KVM: x86/mmu: Use high bits for host/mmu writable masks for EPT SPTEs
Use bits 57 and 58 for HOST_WRITABLE and MMU_WRITABLE when using EPT.
This will allow using bit 11 as a constant MMU_PRESENT, which is
desirable as checking for a shadow-present SPTE is one of the most
common SPTE operations in KVM, particular in hot paths such as page
faults.
EPT is short on low available bits; currently only bit 11 is the only
always-available bit. Bit 10 is also available, but only while KVM
doesn't support mode-based execution. On the other hand, PAE paging
doesn't have _any_ high available bits. Thus, using bit 11 is the only
feasible option for MMU_PRESENT.
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210225204749.1512652-20-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'tools/perf/scripts/python/event_analyzing_sample.py')
0 files changed, 0 insertions, 0 deletions