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| author | Avi Kivity <avi@redhat.com> | 2010-05-12 11:48:18 +0300 |
|---|---|---|
| committer | Avi Kivity <avi@redhat.com> | 2010-05-19 11:41:09 +0300 |
| commit | 3dbe141595faa48a067add3e47bba3205b79d33c (patch) | |
| tree | a7d37004d0021298ed305810543ae6a3a4ed79e2 /Documentation | |
| parent | a3d204e28579427609c3d15d2310127ebaa47d94 (diff) | |
| download | lwn-3dbe141595faa48a067add3e47bba3205b79d33c.tar.gz lwn-3dbe141595faa48a067add3e47bba3205b79d33c.zip | |
KVM: MMU: Segregate shadow pages with different cr0.wp
When cr0.wp=0, we may shadow a gpte having u/s=1 and r/w=0 with an spte
having u/s=0 and r/w=1. This allows excessive access if the guest sets
cr0.wp=1 and accesses through this spte.
Fix by making cr0.wp part of the base role; we'll have different sptes for
the two cases and the problem disappears.
Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/kvm/mmu.txt | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/Documentation/kvm/mmu.txt b/Documentation/kvm/mmu.txt index 0cc28fb84f4f..aaed6ab9d7ab 100644 --- a/Documentation/kvm/mmu.txt +++ b/Documentation/kvm/mmu.txt @@ -163,6 +163,8 @@ Shadow pages contain the following information: 32-bit or 64-bit gptes are in use). role.cr4_nxe: Contains the value of efer.nxe for which the page is valid. + role.cr0_wp: + Contains the value of cr0.wp for which the page is valid. gfn: Either the guest page table containing the translations shadowed by this page, or the base page frame for linear translations. See role.direct. |