From patchwork Fri Oct 16 02:41:10 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Morton X-Patchwork-Id: 11840511 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 0FBA116BC for ; Fri, 16 Oct 2020 02:41:15 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id B16DC20878 for ; Fri, 16 Oct 2020 02:41:14 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="n8pFGoVC" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B16DC20878 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id A4F94940012; Thu, 15 Oct 2020 22:41:13 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id A290394000F; Thu, 15 Oct 2020 22:41:13 -0400 (EDT) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 9644B940012; Thu, 15 Oct 2020 22:41:13 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0240.hostedemail.com [216.40.44.240]) by kanga.kvack.org (Postfix) with ESMTP id 6BF9694000F for ; Thu, 15 Oct 2020 22:41:13 -0400 (EDT) Received: from smtpin17.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 0D9DD181AEF00 for ; Fri, 16 Oct 2020 02:41:13 +0000 (UTC) X-FDA: 77376236826.17.test56_4c0aa6b27219 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin17.hostedemail.com (Postfix) with ESMTP id E9BA1180D0181 for ; Fri, 16 Oct 2020 02:41:12 +0000 (UTC) X-Spam-Summary: 1,0,0,56c0694c3a320ef9,d41d8cd98f00b204,akpm@linux-foundation.org,,RULES_HIT:41:355:379:800:960:967:973:988:989:1260:1345:1359:1381:1431:1437:1534:1541:1711:1730:1747:1777:1792:1963:2393:2525:2559:2563:2682:2685:2859:2902:2933:2937:2939:2942:2945:2947:2951:2954:3022:3138:3139:3140:3141:3142:3165:3352:3865:3866:3867:3870:3871:3872:3874:3934:3936:3938:3941:3944:3947:3950:3953:3956:3959:4321:5007:6261:6653:7576:9025:9545:10004:11026:11473:11658:11914:12043:12048:12114:12296:12297:12517:12519:12555:12679:12986:13069:13255:13311:13357:14181:14384:14721:21080:21451:21627:21740:21939:21990:30054:30070,0,RBL:198.145.29.99:@linux-foundation.org:.lbl8.mailshell.net-64.100.201.201 62.2.0.100;04yfe3rc1ixzs4eu5squu6gjw845xycgsj6rn871n83m5gmeqqmq1j445xe1w56.wie7zht9hyaoacce85mwpuqg7od4xxum63t98z3ru1qufihf4jopfqb6a843jxu.c-lbl8.mailshell.net-223.238.255.100,CacheIP:none,Bayesian:0.5,0.5,0.5,Netcheck:none,DomainCache:0,MSF:not bulk,SPF:fp,MSBL:0,DNSBL:neutral,Custom_rules:0:0 :0,LFtim X-HE-Tag: test56_4c0aa6b27219 X-Filterd-Recvd-Size: 3159 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf09.hostedemail.com (Postfix) with ESMTP for ; Fri, 16 Oct 2020 02:41:12 +0000 (UTC) Received: from localhost.localdomain (c-73-231-172-41.hsd1.ca.comcast.net [73.231.172.41]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 388E220B1F; Fri, 16 Oct 2020 02:41:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1602816071; bh=Or2CQpqLEow/lTsRBd/DMklcdBJcMe9YNSJWWD0WuiM=; h=Date:From:To:Subject:In-Reply-To:From; b=n8pFGoVCrU4r7Z8+//qCK418Srrkz9ZWX/49PwNXIghPOeEXqRC+eTFwJZVDGC7XS lXzdzYC6aka98PLQXS/jpfQk8JAA9skzs/TrRRHDL3WHFgom8TBWwm8AC/MkBW84J6 dsY0dIX9Cumf8VZNQbY5e25iiOGRdpPgyDR/qaD4= Date: Thu, 15 Oct 2020 19:41:10 -0700 From: Andrew Morton To: akpm@linux-foundation.org, aneesh.kumar@linux.ibm.com, anshuman.khandual@arm.com, christophe.leroy@csgroup.eu, linux-mm@kvack.org, mm-commits@vger.kernel.org, mpe@ellerman.id.au, torvalds@linux-foundation.org Subject: [patch 004/156] mm/debug_vm_pgtable/ppc64: avoid setting top bits in radom value Message-ID: <20201016024110.wV3GMM4Jv%akpm@linux-foundation.org> In-Reply-To: <20201015192732.f448da14e9854c7cb7299956@linux-foundation.org> User-Agent: s-nail v14.8.16 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: From: "Aneesh Kumar K.V" Subject: mm/debug_vm_pgtable/ppc64: avoid setting top bits in radom value ppc64 use bit 62 to indicate a pte entry (_PAGE_PTE). Avoid setting that bit in random value. Link: https://lkml.kernel.org/r/20200902114222.181353-4-aneesh.kumar@linux.ibm.com Signed-off-by: Aneesh Kumar K.V Reviewed-by: Anshuman Khandual Cc: Christophe Leroy Cc: Michael Ellerman Signed-off-by: Andrew Morton --- mm/debug_vm_pgtable.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) --- a/mm/debug_vm_pgtable.c~mm-debug_vm_pgtable-ppc64-avoid-setting-top-bits-in-radom-value +++ a/mm/debug_vm_pgtable.c @@ -44,10 +44,17 @@ * entry type. But these bits might affect the ability to clear entries with * pxx_clear() because of how dynamic page table folding works on s390. So * while loading up the entries do not change the lower 4 bits. It does not - * have affect any other platform. + * have affect any other platform. Also avoid the 62nd bit on ppc64 that is + * used to mark a pte entry. */ -#define S390_MASK_BITS 4 -#define RANDOM_ORVALUE GENMASK(BITS_PER_LONG - 1, S390_MASK_BITS) +#define S390_SKIP_MASK GENMASK(3, 0) +#if __BITS_PER_LONG == 64 +#define PPC64_SKIP_MASK GENMASK(62, 62) +#else +#define PPC64_SKIP_MASK 0x0 +#endif +#define ARCH_SKIP_MASK (S390_SKIP_MASK | PPC64_SKIP_MASK) +#define RANDOM_ORVALUE (GENMASK(BITS_PER_LONG - 1, 0) & ~ARCH_SKIP_MASK) #define RANDOM_NZVALUE GENMASK(7, 0) static void __init pte_basic_tests(unsigned long pfn, pgprot_t prot)