diff options
| author | Luiz Capitulino <lcapitulino@redhat.com> | 2013-05-28 14:19:22 -0400 |
|---|---|---|
| committer | Luiz Capitulino <lcapitulino@redhat.com> | 2013-05-31 09:02:24 -0400 |
| commit | fbc2ed9518efcdcdcbf0adb9539c17a65addd20a (patch) | |
| tree | 1cea742edb48e1997991a0bd3512b0eeb104ff72 /target-i386 | |
| parent | a678e26cbe89f7a27cbce794c2c2784571ee9d21 (diff) | |
target-i386: fix abort on bad PML4E/PDPTE/PDE/PTE addresses
The code used to walk IA-32e page-tables, and possibly PAE page-tables,
uses the bit mask ~0xfff to get the next PML4E/PDPTE/PDE/PTE address.
However, as we use a uint64_t to store the resulting address, that mask
gets expanded to 0xfffffffffffff000 which not only ends up selecting
reserved bits but also selects the XD bit (execute-disable) which
happens to be enabled by Windows 8, causing qemu_get_ram_ptr() to abort.
This commit fixes that problem by replacing ~0xfff by a correct mask
that only selects the address bit range (ie. bits 51:12).
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Diffstat (limited to 'target-i386')
| -rw-r--r-- | target-i386/arch_memory_mapping.c | 10 |
1 files changed, 6 insertions, 4 deletions
diff --git a/target-i386/arch_memory_mapping.c b/target-i386/arch_memory_mapping.c index 844893f44d..24884bd482 100644 --- a/target-i386/arch_memory_mapping.c +++ b/target-i386/arch_memory_mapping.c @@ -75,6 +75,8 @@ static void walk_pte2(MemoryMappingList *list, } /* PAE Paging or IA-32e Paging */ +#define PLM4_ADDR_MASK 0xffffffffff000 /* selects bits 51:12 */ + static void walk_pde(MemoryMappingList *list, hwaddr pde_start_addr, int32_t a20_mask, target_ulong start_line_addr) { @@ -105,7 +107,7 @@ static void walk_pde(MemoryMappingList *list, hwaddr pde_start_addr, continue; } - pte_start_addr = (pde & ~0xfff) & a20_mask; + pte_start_addr = (pde & PLM4_ADDR_MASK) & a20_mask; walk_pte(list, pte_start_addr, a20_mask, line_addr); } } @@ -208,7 +210,7 @@ static void walk_pdpe(MemoryMappingList *list, continue; } - pde_start_addr = (pdpe & ~0xfff) & a20_mask; + pde_start_addr = (pdpe & PLM4_ADDR_MASK) & a20_mask; walk_pde(list, pde_start_addr, a20_mask, line_addr); } } @@ -231,7 +233,7 @@ static void walk_pml4e(MemoryMappingList *list, } line_addr = ((i & 0x1ffULL) << 39) | (0xffffULL << 48); - pdpe_start_addr = (pml4e & ~0xfff) & a20_mask; + pdpe_start_addr = (pml4e & PLM4_ADDR_MASK) & a20_mask; walk_pdpe(list, pdpe_start_addr, a20_mask, line_addr); } } @@ -249,7 +251,7 @@ int cpu_get_memory_mapping(MemoryMappingList *list, CPUArchState *env) if (env->hflags & HF_LMA_MASK) { hwaddr pml4e_addr; - pml4e_addr = (env->cr[3] & ~0xfff) & env->a20_mask; + pml4e_addr = (env->cr[3] & PLM4_ADDR_MASK) & env->a20_mask; walk_pml4e(list, pml4e_addr, env->a20_mask); } else #endif |