From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from e28smtp02.in.ibm.com (e28smtp02.in.ibm.com [122.248.162.2]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "e28smtp02.in.ibm.com", Issuer "GeoTrust SSL CA" (not verified)) by ozlabs.org (Postfix) with ESMTPS id 9B5902C030C for ; Fri, 31 May 2013 21:03:53 +1000 (EST) Received: from /spool/local by e28smtp02.in.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Fri, 31 May 2013 16:26:44 +0530 Received: from d28relay05.in.ibm.com (d28relay05.in.ibm.com [9.184.220.62]) by d28dlp01.in.ibm.com (Postfix) with ESMTP id 19CFDE0053 for ; Fri, 31 May 2013 16:36:23 +0530 (IST) Received: from d28av04.in.ibm.com (d28av04.in.ibm.com [9.184.220.66]) by d28relay05.in.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id r4VB3ZoW4522332 for ; Fri, 31 May 2013 16:33:36 +0530 Received: from d28av04.in.ibm.com (loopback [127.0.0.1]) by d28av04.in.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id r4VB3cLd007990 for ; Fri, 31 May 2013 21:03:39 +1000 From: "Aneesh Kumar K.V" To: benh@kernel.crashing.org Subject: [PATCH] powerpc/mm: Always invalidate tlb on hpte invalidate and update Date: Fri, 31 May 2013 16:33:24 +0530 Message-Id: <1369998204-31490-1-git-send-email-aneesh.kumar@linux.vnet.ibm.com> Cc: linuxppc-dev@lists.ozlabs.org, "Aneesh Kumar K.V" List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , From: "Aneesh Kumar K.V" 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 --- 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