if (!spapr->htab) {
kvmppc_write_hpte(ptex, pte0, pte1);
} else {
- stq_p(spapr->htab + offset, pte0);
- stq_p(spapr->htab + offset + HASH_PTE_SIZE_64 / 2, pte1);
+ if (pte0 & HPTE64_V_VALID) {
+ stq_p(spapr->htab + offset + HASH_PTE_SIZE_64 / 2, pte1);
+ /*
+ * When setting valid, we write PTE1 first. This ensures
+ * proper synchronization with the reading code in
+ * ppc_hash64_pteg_search()
+ */
+ smp_wmb();
+ stq_p(spapr->htab + offset, pte0);
+ } else {
+ stq_p(spapr->htab + offset, pte0);
+ /*
+ * When clearing it we set PTE0 first. This ensures proper
+ * synchronization with the reading code in
+ * ppc_hash64_pteg_search()
+ */
+ smp_wmb();
+ stq_p(spapr->htab + offset + HASH_PTE_SIZE_64 / 2, pte1);
+ }
}
}
for (i = 0; i < HPTES_PER_GROUP; i++) {
pte0 = ppc_hash32_load_hpte0(cpu, pte_offset);
+ /*
+ * pte0 contains the valid bit and must be read before pte1,
+ * otherwise we might see an old pte1 with a new valid bit and
+ * thus an inconsistent hpte value
+ */
+ smp_rmb();
pte1 = ppc_hash32_load_hpte1(cpu, pte_offset);
if ((pte0 & HPTE32_V_VALID)
}
for (i = 0; i < HPTES_PER_GROUP; i++) {
pte0 = ppc_hash64_hpte0(cpu, pteg, i);
+ /*
+ * pte0 contains the valid bit and must be read before pte1,
+ * otherwise we might see an old pte1 with a new valid bit and
+ * thus an inconsistent hpte value
+ */
+ smp_rmb();
pte1 = ppc_hash64_hpte1(cpu, pteg, i);
/* This compares V, B, H (secondary) and the AVPN */