diff options
| author | Cédric Le Goater <clg@fr.ibm.com> | 2014-02-04 18:21:39 +0100 |
|---|---|---|
| committer | Alexander Graf <agraf@suse.de> | 2014-03-05 03:06:25 +0100 |
| commit | 363248e8c92c6331253e2a768884c69183805050 (patch) | |
| tree | 6fbc93ee17afab3f7efdf6c69dd496169d2fad80 | |
| parent | 0dc083fe10c5cc848f36498b9157a336cbc8c7c1 (diff) | |
mmu-hash64: fix Virtual Page Class Key Protection
commit f80872e21c07edd06eb343eeeefc8af404b518a6 (mmu-hash64: Implement
Virtual Page Class Key Protection) added a new page protection
mechanism based on page keys and the AMR register to control access.
The AMR register allows or prohibits reads and/or writes on a page
depending on the control bits associated to the key. A store or a load
is only permitted if the associate bit is 0 (Power ISA), and not 1 as
the code is currently doing. This patch modifies ppc_hash64_amr_prot()
to correct the protection check.
This issue was unvailed by commit ccfb53ed6360cac0d5f6f7915ca9ae7eed866412
(target-ppc: fix Authority Mask Register init value) which changed the
initialisation value of the AMR register to 0.
Signed-off-by: Cédric Le Goater <clg@fr.ibm.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
| -rw-r--r-- | target-ppc/mmu-hash64.c | 16 |
1 files changed, 12 insertions, 4 deletions
diff --git a/target-ppc/mmu-hash64.c b/target-ppc/mmu-hash64.c index 67fc1b5dec..c1c33b0f9a 100644 --- a/target-ppc/mmu-hash64.c +++ b/target-ppc/mmu-hash64.c @@ -278,12 +278,12 @@ static int ppc_hash64_pte_prot(CPUPPCState *env, static int ppc_hash64_amr_prot(CPUPPCState *env, ppc_hash_pte64_t pte) { int key, amrbits; - int prot = PAGE_EXEC; + int prot = PAGE_READ | PAGE_WRITE | PAGE_EXEC; /* Only recent MMUs implement Virtual Page Class Key Protection */ if (!(env->mmu_model & POWERPC_MMU_AMR)) { - return PAGE_READ | PAGE_WRITE | PAGE_EXEC; + return prot; } key = HPTE64_R_KEY(pte.pte1); @@ -292,11 +292,19 @@ static int ppc_hash64_amr_prot(CPUPPCState *env, ppc_hash_pte64_t pte) /* fprintf(stderr, "AMR protection: key=%d AMR=0x%" PRIx64 "\n", key, */ /* env->spr[SPR_AMR]); */ + /* + * A store is permitted if the AMR bit is 0. Remove write + * protection if it is set. + */ if (amrbits & 0x2) { - prot |= PAGE_WRITE; + prot &= ~PAGE_WRITE; } + /* + * A load is permitted if the AMR bit is 0. Remove read + * protection if it is set. + */ if (amrbits & 0x1) { - prot |= PAGE_READ; + prot &= ~PAGE_READ; } return prot; |