[PATCH] powerpc/mm: Always invalidate tlb on hpte invalidate and update
From: Aneesh Kumar K.V <hidden>
Date: 2013-05-31 11:03:53
From: "Aneesh Kumar K.V" <redacted> If a hash bucket gets full, we "evict" a more/less random entry from it. When we do that we don't invalidate the TLB (hpte_remove) because we assume the old translation is still technically "valid". This implies that when we are invalidating or updating pte, even if HPTE entry is not valid we should do a tlb invalidate. Signed-off-by: Aneesh Kumar K.V <redacted> --- arch/powerpc/mm/hash_native_64.c | 30 ++++++++++++++++++++++-------- 1 file changed, 22 insertions(+), 8 deletions(-)
diff --git a/arch/powerpc/mm/hash_native_64.c b/arch/powerpc/mm/hash_native_64.c
index 6a2aead..4c122c3 100644
--- a/arch/powerpc/mm/hash_native_64.c
+++ b/arch/powerpc/mm/hash_native_64.c@@ -336,11 +336,18 @@ static long native_hpte_updatepp(unsigned long slot, unsigned long newpp, hpte_v = hptep->v; actual_psize = hpte_actual_psize(hptep, psize); + /* + * We need to invalidate the TLB always because hpte_remove doesn't do + * a tlb invalidate. If a hash bucket gets full, we "evict" a more/less + * random entry from it. When we do that we don't invalidate the TLB + * (hpte_remove) because we assume the old translation is still + * technically "valid". + */ if (actual_psize < 0) { - native_unlock_hpte(hptep); - return -1; + actual_psize = psize; + ret = -1; + goto err_out; } - /* Even if we miss, we need to invalidate the TLB */ if (!HPTE_V_COMPARE(hpte_v, want_v)) { DBG_LOW(" -> miss\n"); ret = -1;
@@ -350,6 +357,7 @@ static long native_hpte_updatepp(unsigned long slot, unsigned long newpp, hptep->r = (hptep->r & ~(HPTE_R_PP | HPTE_R_N)) | (newpp & (HPTE_R_PP | HPTE_R_N | HPTE_R_C)); } +err_out: native_unlock_hpte(hptep); /* Ensure it is out of the tlb too. */
@@ -409,7 +417,7 @@ static void native_hpte_updateboltedpp(unsigned long newpp, unsigned long ea, hptep = htab_address + slot; actual_psize = hpte_actual_psize(hptep, psize); if (actual_psize < 0) - return; + actual_psize = psize; /* Update the HPTE */ hptep->r = (hptep->r & ~(HPTE_R_PP | HPTE_R_N)) |
@@ -437,21 +445,27 @@ static void native_hpte_invalidate(unsigned long slot, unsigned long vpn, hpte_v = hptep->v; actual_psize = hpte_actual_psize(hptep, psize); + /* + * We need to invalidate the TLB always because hpte_remove doesn't do + * a tlb invalidate. If a hash bucket gets full, we "evict" a more/less + * random entry from it. When we do that we don't invalidate the TLB + * (hpte_remove) because we assume the old translation is still + * technically "valid". + */ if (actual_psize < 0) { + actual_psize = psize; native_unlock_hpte(hptep); - local_irq_restore(flags); - return; + goto err_out; } - /* Even if we miss, we need to invalidate the TLB */ if (!HPTE_V_COMPARE(hpte_v, want_v)) native_unlock_hpte(hptep); else /* Invalidate the hpte. NOTE: this also unlocks it */ hptep->v = 0; +err_out: /* Invalidate the TLB */ tlbie(vpn, psize, actual_psize, ssize, local); - local_irq_restore(flags); }
--
1.8.1.2