| commit | a28fe7dc1939333c81b895cdced81c69eb7c5ad0 | |
| author | Paolo Bonzini <pbonzini@redhat.com> | |
| Fri, 22 Dec 2023 08:52:27 +0000 (22 09:52 +0100) | ||
| committer | Paolo Bonzini <pbonzini@redhat.com> | |
| Tue, 27 Feb 2024 23:23:39 +0000 (28 00:23 +0100) | ||
| tree | f3a54181fc320246e52dfd794dbc1d03028e3469 | treesnapshot (tar.gz zip) |
| parent | b1661801c184119a10ad6cbc3b80330fc22e7b2c | commitdiff |
target/i386: remove unnecessary/wrong application of the A20 mask
If ptw_translate() does a MMU_PHYS_IDX access, the A20 mask is already
applied in get_physical_address(), which is called via probe_access_full()
and x86_cpu_tlb_fill().
If ptw_translate() on the other hand does a MMU_NESTED_IDX access,
the A20 mask must not be applied to the address that is looked up in
the nested page tables; it must be applied only to the addresses that
hold the NPT entries (which is achieved via MMU_PHYS_IDX, per the
previous paragraph).
Therefore, we can remove A20 masking from the computation of the page
table entry's address, and let get_physical_address() or mmu_translate()
apply it when they know they are returning a host-physical address.
Cc: qemu-stable@nongnu.org
Fixes: 4a1e9d4d11c ("target/i386: Use atomic operations for pte updates", 2022-10-18)
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
If ptw_translate() does a MMU_PHYS_IDX access, the A20 mask is already
applied in get_physical_address(), which is called via probe_access_full()
and x86_cpu_tlb_fill().
If ptw_translate() on the other hand does a MMU_NESTED_IDX access,
the A20 mask must not be applied to the address that is looked up in
the nested page tables; it must be applied only to the addresses that
hold the NPT entries (which is achieved via MMU_PHYS_IDX, per the
previous paragraph).
Therefore, we can remove A20 masking from the computation of the page
table entry's address, and let get_physical_address() or mmu_translate()
apply it when they know they are returning a host-physical address.
Cc: qemu-stable@nongnu.org
Fixes: 4a1e9d4d11c ("target/i386: Use atomic operations for pte updates", 2022-10-18)
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| target/i386/tcg/sysemu/excp_helper.c | diffblobblamehistory |