diff options
| author | Paul Mackerras <paulus@samba.org> | 2013-09-20 14:52:47 +1000 |
|---|---|---|
| committer | Alexander Graf <agraf@suse.de> | 2013-10-17 14:45:04 +0200 |
| commit | 5cd92a9521d35013fff904d3c805323027a33d73 (patch) | |
| tree | 94037f1b656b8a029749061660a7575a8941dd5e /arch/powerpc/kvm/book3s_pr_papr.c | |
| parent | 03a9c90334d611c3006ac9569579f25f64812bc1 (diff) | |
| download | linux-5cd92a9521d35013fff904d3c805323027a33d73.tar.bz2 | |
KVM: PPC: Book3S PR: Correct errors in H_ENTER implementation
The implementation of H_ENTER in PR KVM has some errors:
* With H_EXACT not set, if the HPTEG is full, we return H_PTEG_FULL
as the return value of kvmppc_h_pr_enter, but the caller is expecting
one of the EMULATE_* values. The H_PTEG_FULL needs to go in the
guest's R3 instead.
* With H_EXACT set, if the selected HPTE is already valid, the H_ENTER
call should return a H_PTEG_FULL error.
This fixes these errors and also makes it write only the selected HPTE,
not the whole group, since only the selected HPTE has been modified.
This also micro-optimizes the calculations involving pte_index and i.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
Diffstat (limited to 'arch/powerpc/kvm/book3s_pr_papr.c')
| -rw-r--r-- | arch/powerpc/kvm/book3s_pr_papr.c | 19 |
1 files changed, 14 insertions, 5 deletions
diff --git a/arch/powerpc/kvm/book3s_pr_papr.c b/arch/powerpc/kvm/book3s_pr_papr.c index da0e0bc268bd..38f189975fe1 100644 --- a/arch/powerpc/kvm/book3s_pr_papr.c +++ b/arch/powerpc/kvm/book3s_pr_papr.c @@ -21,6 +21,8 @@ #include <asm/kvm_ppc.h> #include <asm/kvm_book3s.h> +#define HPTE_SIZE 16 /* bytes per HPT entry */ + static unsigned long get_pteg_addr(struct kvm_vcpu *vcpu, long pte_index) { struct kvmppc_vcpu_book3s *vcpu_book3s = to_book3s(vcpu); @@ -40,32 +42,39 @@ static int kvmppc_h_pr_enter(struct kvm_vcpu *vcpu) long pte_index = kvmppc_get_gpr(vcpu, 5); unsigned long pteg[2 * 8]; unsigned long pteg_addr, i, *hpte; + long int ret; + i = pte_index & 7; pte_index &= ~7UL; pteg_addr = get_pteg_addr(vcpu, pte_index); copy_from_user(pteg, (void __user *)pteg_addr, sizeof(pteg)); hpte = pteg; + ret = H_PTEG_FULL; if (likely((flags & H_EXACT) == 0)) { - pte_index &= ~7UL; for (i = 0; ; ++i) { if (i == 8) - return H_PTEG_FULL; + goto done; if ((*hpte & HPTE_V_VALID) == 0) break; hpte += 2; } } else { - i = kvmppc_get_gpr(vcpu, 5) & 7UL; hpte += i * 2; + if (*hpte & HPTE_V_VALID) + goto done; } hpte[0] = kvmppc_get_gpr(vcpu, 6); hpte[1] = kvmppc_get_gpr(vcpu, 7); - copy_to_user((void __user *)pteg_addr, pteg, sizeof(pteg)); - kvmppc_set_gpr(vcpu, 3, H_SUCCESS); + pteg_addr += i * HPTE_SIZE; + copy_to_user((void __user *)pteg_addr, hpte, HPTE_SIZE); kvmppc_set_gpr(vcpu, 4, pte_index | i); + ret = H_SUCCESS; + + done: + kvmppc_set_gpr(vcpu, 3, ret); return EMULATE_DONE; } |