KVM: PPC: Book3S PR: Do dcbz32 patching with big endian instructions

When the host CPU we're running on doesn't support dcbz32 itself, but the
guest wants to have dcbz only clear 32 bytes of data, we loop through every
executable mapped page to search for dcbz instructions and patch them with
a special privileged instruction that we emulate as dcbz32.

The only guests that want to see dcbz act as 32byte are book3s_32 guests, so
we don't have to worry about little endian instruction ordering. So let's
just always search for big endian dcbz instructions, also when we're on a
little endian host.

Signed-off-by: Alexander Graf <agraf@suse.de>
This commit is contained in:
Alexander Graf 2014-04-24 13:52:01 +02:00
parent 5deb8e7ad8
commit cd087eefe6
2 changed files with 3 additions and 3 deletions

View File

@ -131,7 +131,7 @@ static hva_t kvmppc_mmu_book3s_32_get_pteg(struct kvm_vcpu *vcpu,
pteg = (vcpu_book3s->sdr1 & 0xffff0000) | hash;
dprintk("MMU: pc=0x%lx eaddr=0x%lx sdr1=0x%llx pteg=0x%x vsid=0x%x\n",
kvmppc_get_pc(&vcpu_book3s->vcpu), eaddr, vcpu_book3s->sdr1, pteg,
kvmppc_get_pc(vcpu), eaddr, vcpu_book3s->sdr1, pteg,
sr_vsid(sre));
r = gfn_to_hva(vcpu->kvm, pteg >> PAGE_SHIFT);

View File

@ -428,8 +428,8 @@ static void kvmppc_patch_dcbz(struct kvm_vcpu *vcpu, struct kvmppc_pte *pte)
/* patch dcbz into reserved instruction, so we trap */
for (i=hpage_offset; i < hpage_offset + (HW_PAGE_SIZE / 4); i++)
if ((page[i] & 0xff0007ff) == INS_DCBZ)
page[i] &= 0xfffffff7;
if ((be32_to_cpu(page[i]) & 0xff0007ff) == INS_DCBZ)
page[i] &= cpu_to_be32(0xfffffff7);
kunmap_atomic(page);
put_page(hpage);