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| author | Alexander Graf <agraf@suse.de> | 2010-07-29 14:48:05 +0200 |
|---|---|---|
| committer | Avi Kivity <avi@redhat.com> | 2010-10-24 10:50:56 +0200 |
| commit | 7810927760a0d16d7a41be4dab895fbbf9445bc0 (patch) | |
| tree | f215dd900d26d691c05f9b48233b7ef910b4fb1d /arch/powerpc/kernel/kvm.c | |
| parent | 819a63dc792b0888edd3eda306a9e1e049dcbb1c (diff) | |
| download | linux-7810927760a0d16d7a41be4dab895fbbf9445bc0.tar.gz linux-7810927760a0d16d7a41be4dab895fbbf9445bc0.tar.bz2 linux-7810927760a0d16d7a41be4dab895fbbf9445bc0.zip | |
KVM: PPC: PV mtmsrd L=0 and mtmsr
There is also a form of mtmsr where all bits need to be addressed. While the
PPC64 Linux kernel behaves resonably well here, on PPC32 we do not have an
L=1 form. It does mtmsr even for simple things like only changing EE.
So we need to hook into that one as well and check for a mask of bits that we
deem safe to change from within guest context.
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
Diffstat (limited to 'arch/powerpc/kernel/kvm.c')
| -rw-r--r-- | arch/powerpc/kernel/kvm.c | 51 |
1 files changed, 51 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/kvm.c b/arch/powerpc/kernel/kvm.c index 717ab0dded25..8ac57e2c52fa 100644 --- a/arch/powerpc/kernel/kvm.c +++ b/arch/powerpc/kernel/kvm.c @@ -63,7 +63,9 @@ #define KVM_INST_MTSPR_DSISR 0x7c1203a6 #define KVM_INST_TLBSYNC 0x7c00046c +#define KVM_INST_MTMSRD_L0 0x7c000164 #define KVM_INST_MTMSRD_L1 0x7c010164 +#define KVM_INST_MTMSR 0x7c000124 static bool kvm_patching_worked = true; static char kvm_tmp[1024 * 1024]; @@ -176,6 +178,49 @@ static void kvm_patch_ins_mtmsrd(u32 *inst, u32 rt) kvm_patch_ins_b(inst, distance_start); } +extern u32 kvm_emulate_mtmsr_branch_offs; +extern u32 kvm_emulate_mtmsr_reg1_offs; +extern u32 kvm_emulate_mtmsr_reg2_offs; +extern u32 kvm_emulate_mtmsr_reg3_offs; +extern u32 kvm_emulate_mtmsr_orig_ins_offs; +extern u32 kvm_emulate_mtmsr_len; +extern u32 kvm_emulate_mtmsr[]; + +static void kvm_patch_ins_mtmsr(u32 *inst, u32 rt) +{ + u32 *p; + int distance_start; + int distance_end; + ulong next_inst; + + p = kvm_alloc(kvm_emulate_mtmsr_len * 4); + if (!p) + return; + + /* Find out where we are and put everything there */ + distance_start = (ulong)p - (ulong)inst; + next_inst = ((ulong)inst + 4); + distance_end = next_inst - (ulong)&p[kvm_emulate_mtmsr_branch_offs]; + + /* Make sure we only write valid b instructions */ + if (distance_start > KVM_INST_B_MAX) { + kvm_patching_worked = false; + return; + } + + /* Modify the chunk to fit the invocation */ + memcpy(p, kvm_emulate_mtmsr, kvm_emulate_mtmsr_len * 4); + p[kvm_emulate_mtmsr_branch_offs] |= distance_end & KVM_INST_B_MASK; + p[kvm_emulate_mtmsr_reg1_offs] |= rt; + p[kvm_emulate_mtmsr_reg2_offs] |= rt; + p[kvm_emulate_mtmsr_reg3_offs] |= rt; + p[kvm_emulate_mtmsr_orig_ins_offs] = *inst; + flush_icache_range((ulong)p, (ulong)p + kvm_emulate_mtmsr_len * 4); + + /* Patch the invocation */ + kvm_patch_ins_b(inst, distance_start); +} + static void kvm_map_magic_page(void *data) { kvm_hypercall2(KVM_HC_PPC_MAP_MAGIC_PAGE, @@ -256,6 +301,12 @@ static void kvm_check_ins(u32 *inst) if (get_rt(inst_rt) < 30) kvm_patch_ins_mtmsrd(inst, inst_rt); break; + case KVM_INST_MTMSR: + case KVM_INST_MTMSRD_L0: + /* We use r30 and r31 during the hook */ + if (get_rt(inst_rt) < 30) + kvm_patch_ins_mtmsr(inst, inst_rt); + break; } switch (_inst) { |