From patchwork Fri Apr 10 21:33:36 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Morton X-Patchwork-Id: 11483673 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 B5C5881 for ; Fri, 10 Apr 2020 21:33:40 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 7647E21556 for ; Fri, 10 Apr 2020 21:33:40 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="PZxNiLCc" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7647E21556 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 7DDC48E007B; Fri, 10 Apr 2020 17:33:39 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id 78F058E0067; Fri, 10 Apr 2020 17:33:39 -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 6CBD38E007B; Fri, 10 Apr 2020 17:33:39 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0036.hostedemail.com [216.40.44.36]) by kanga.kvack.org (Postfix) with ESMTP id 54DB28E0067 for ; Fri, 10 Apr 2020 17:33:39 -0400 (EDT) Received: from smtpin18.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 0B560180AD802 for ; Fri, 10 Apr 2020 21:33:39 +0000 (UTC) X-FDA: 76693247358.18.fog99_3ce97742a6d02 X-Spam-Summary: 2,0,0,fe6e6381985c1252,d41d8cd98f00b204,akpm@linux-foundation.org,,RULES_HIT:2:41:355:379:800:960:967:973:988:989:1260:1263:1345:1359:1381:1431:1437:1535:1605:1730:1747:1777:1792:2194:2199:2393:2525:2559:2563:2682:2685:2693:2859:2897:2902:2903:2918:2933:2937:2939:2942:2945:2947:2951:2954:3022:3138:3139:3140:3141:3142:3167:3865:3866:3867:3868:3870:3871:3872:3874:3934:3936:3938:3941:3944:3947:3950:3953:3956:3959:4050:4120:4250:4321:4605:5007:6117:6261:6653:6737:6738:7576:7875:7903:7974:8599:8603:9025:9036:9545:10004:10913:11026:11473:11658:11914:12043:12048:12296:12297:12438:12517:12519:12555:12679:12783:12986:13141:13161:13229:13230:13846:13972:21063:21080:21451:21611:21627:21796:21939:21990:30012:30036:30054:30064:30070,0,RBL:198.145.29.99:@linux-foundation.org:.lbl8.mailshell.net-64.100.201.201 62.2.0.100,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,LFtime:1,LUA_SUMMARY:none X-HE-Tag: fog99_3ce97742a6d02 X-Filterd-Recvd-Size: 9665 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf09.hostedemail.com (Postfix) with ESMTP for ; Fri, 10 Apr 2020 21:33:37 +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 713F82087E; Fri, 10 Apr 2020 21:33:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1586554417; bh=yjPwgQuOXpm+4ju3UWemqKNxWKd2Mh2qwg7EHR/OxV4=; h=Date:From:To:Subject:In-Reply-To:From; b=PZxNiLCcak8RdNq6eHVVx6KAoa9xu1qBaCo1dljqkNAuVWU0EvY7VwJ+GvWiL45CL 0rHQ1R6beGpfxqxbARngh/ZmZre0YIFnTpesLXwKmp2QseNSQzWwwSMIi+gk486B8E Uc8+99MqUglMrUyXSrTEYWR2RcLemsm0CT9QdaOs= Date: Fri, 10 Apr 2020 14:33:36 -0700 From: Andrew Morton To: akpm@linux-foundation.org, benh@kernel.crashing.org, bp@alien8.de, catalin.marinas@arm.com, dan.j.williams@intel.com, dave.hansen@linux.intel.com, david@redhat.com, ebadger@gigaio.com, hch@lst.de, hpa@zytor.com, jgg@ziepe.ca, linux-mm@kvack.org, logang@deltatee.com, luto@kernel.org, mhocko@suse.com, mingo@redhat.com, mm-commits@vger.kernel.org, mpe@ellerman.id.au, paulus@samba.org, peterz@infradead.org, tglx@linutronix.de, torvalds@linux-foundation.org, will@kernel.org Subject: [patch 24/35] mm/memory_hotplug: add pgprot_t to mhp_params Message-ID: <20200410213336.7dA-akMbT%akpm@linux-foundation.org> In-Reply-To: <20200410143047.bf34a933ce1affdc042c7c80@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: Logan Gunthorpe Subject: mm/memory_hotplug: add pgprot_t to mhp_params devm_memremap_pages() is currently used by the PCI P2PDMA code to create struct page mappings for IO memory. At present, these mappings are created with PAGE_KERNEL which implies setting the PAT bits to be WB. However, on x86, an mtrr register will typically override this and force the cache type to be UC-. In the case firmware doesn't set this register it is effectively WB and will typically result in a machine check exception when it's accessed. Other arches are not currently likely to function correctly seeing they don't have any MTRR registers to fall back on. To solve this, provide a way to specify the pgprot value explicitly to arch_add_memory(). Of the arches that support MEMORY_HOTPLUG: x86_64, and arm64 need a simple change to pass the pgprot_t down to their respective functions which set up the page tables. For x86_32, set the page tables explicitly using _set_memory_prot() (seeing they are already mapped). For ia64, s390 and sh, reject anything but PAGE_KERNEL settings -- this should be fine, for now, seeing these architectures don't support ZONE_DEVICE. A check in __add_pages() is also added to ensure the pgprot parameter was set for all arches. Link: http://lkml.kernel.org/r/20200306170846.9333-7-logang@deltatee.com Signed-off-by: Logan Gunthorpe Acked-by: David Hildenbrand Acked-by: Michal Hocko Acked-by: Dan Williams Cc: Andy Lutomirski Cc: Benjamin Herrenschmidt Cc: Borislav Petkov Cc: Catalin Marinas Cc: Christoph Hellwig Cc: Dave Hansen Cc: Eric Badger Cc: "H. Peter Anvin" Cc: Ingo Molnar Cc: Jason Gunthorpe Cc: Michael Ellerman Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Will Deacon Signed-off-by: Andrew Morton --- arch/arm64/mm/mmu.c | 3 ++- arch/ia64/mm/init.c | 3 +++ arch/powerpc/mm/mem.c | 3 ++- arch/s390/mm/init.c | 3 +++ arch/sh/mm/init.c | 3 +++ arch/x86/mm/init_32.c | 12 ++++++++++++ arch/x86/mm/init_64.c | 2 +- include/linux/memory_hotplug.h | 3 +++ mm/memory_hotplug.c | 5 ++++- mm/memremap.c | 6 +++--- 10 files changed, 36 insertions(+), 7 deletions(-) --- a/arch/arm64/mm/mmu.c~mm-memory_hotplug-add-pgprot_t-to-mhp_params +++ a/arch/arm64/mm/mmu.c @@ -1382,7 +1382,8 @@ int arch_add_memory(int nid, u64 start, flags = NO_BLOCK_MAPPINGS | NO_CONT_MAPPINGS; __create_pgd_mapping(swapper_pg_dir, start, __phys_to_virt(start), - size, PAGE_KERNEL, __pgd_pgtable_alloc, flags); + size, params->pgprot, __pgd_pgtable_alloc, + flags); memblock_clear_nomap(start, size); --- a/arch/ia64/mm/init.c~mm-memory_hotplug-add-pgprot_t-to-mhp_params +++ a/arch/ia64/mm/init.c @@ -676,6 +676,9 @@ int arch_add_memory(int nid, u64 start, unsigned long nr_pages = size >> PAGE_SHIFT; int ret; + if (WARN_ON_ONCE(params->pgprot.pgprot != PAGE_KERNEL.pgprot)) + return -EINVAL; + ret = __add_pages(nid, start_pfn, nr_pages, params); if (ret) printk("%s: Problem encountered in __add_pages() as ret=%d\n", --- a/arch/powerpc/mm/mem.c~mm-memory_hotplug-add-pgprot_t-to-mhp_params +++ a/arch/powerpc/mm/mem.c @@ -132,7 +132,8 @@ int __ref arch_add_memory(int nid, u64 s resize_hpt_for_hotplug(memblock_phys_mem_size()); start = (unsigned long)__va(start); - rc = create_section_mapping(start, start + size, nid, PAGE_KERNEL); + rc = create_section_mapping(start, start + size, nid, + params->pgprot); if (rc) { pr_warn("Unable to create mapping for hot added memory 0x%llx..0x%llx: %d\n", start, start + size, rc); --- a/arch/s390/mm/init.c~mm-memory_hotplug-add-pgprot_t-to-mhp_params +++ a/arch/s390/mm/init.c @@ -277,6 +277,9 @@ int arch_add_memory(int nid, u64 start, if (WARN_ON_ONCE(params->altmap)) return -EINVAL; + if (WARN_ON_ONCE(params->pgprot.pgprot != PAGE_KERNEL.pgprot)) + return -EINVAL; + rc = vmem_add_mapping(start, size); if (rc) return rc; --- a/arch/sh/mm/init.c~mm-memory_hotplug-add-pgprot_t-to-mhp_params +++ a/arch/sh/mm/init.c @@ -412,6 +412,9 @@ int arch_add_memory(int nid, u64 start, unsigned long nr_pages = size >> PAGE_SHIFT; int ret; + if (WARN_ON_ONCE(params->pgprot.pgprot != PAGE_KERNEL.pgprot) + return -EINVAL; + /* We only have ZONE_NORMAL, so this is easy.. */ ret = __add_pages(nid, start_pfn, nr_pages, params); if (unlikely(ret)) --- a/arch/x86/mm/init_32.c~mm-memory_hotplug-add-pgprot_t-to-mhp_params +++ a/arch/x86/mm/init_32.c @@ -824,6 +824,18 @@ int arch_add_memory(int nid, u64 start, { unsigned long start_pfn = start >> PAGE_SHIFT; unsigned long nr_pages = size >> PAGE_SHIFT; + int ret; + + /* + * The page tables were already mapped at boot so if the caller + * requests a different mapping type then we must change all the + * pages with __set_memory_prot(). + */ + if (params->pgprot.pgprot != PAGE_KERNEL.pgprot) { + ret = __set_memory_prot(start, nr_pages, params->pgprot); + if (ret) + return ret; + } return __add_pages(nid, start_pfn, nr_pages, params); } --- a/arch/x86/mm/init_64.c~mm-memory_hotplug-add-pgprot_t-to-mhp_params +++ a/arch/x86/mm/init_64.c @@ -867,7 +867,7 @@ int arch_add_memory(int nid, u64 start, unsigned long start_pfn = start >> PAGE_SHIFT; unsigned long nr_pages = size >> PAGE_SHIFT; - init_memory_mapping(start, start + size, PAGE_KERNEL); + init_memory_mapping(start, start + size, params->pgprot); return add_pages(nid, start_pfn, nr_pages, params); } --- a/include/linux/memory_hotplug.h~mm-memory_hotplug-add-pgprot_t-to-mhp_params +++ a/include/linux/memory_hotplug.h @@ -60,9 +60,12 @@ enum { /* * Extended parameters for memory hotplug: * altmap: alternative allocator for memmap array (optional) + * pgprot: page protection flags to apply to newly created page tables + * (required) */ struct mhp_params { struct vmem_altmap *altmap; + pgprot_t pgprot; }; /* --- a/mm/memory_hotplug.c~mm-memory_hotplug-add-pgprot_t-to-mhp_params +++ a/mm/memory_hotplug.c @@ -311,6 +311,9 @@ int __ref __add_pages(int nid, unsigned int err; struct vmem_altmap *altmap = params->altmap; + if (WARN_ON_ONCE(!params->pgprot.pgprot)) + return -EINVAL; + err = check_hotplug_memory_addressable(pfn, nr_pages); if (err) return err; @@ -1002,7 +1005,7 @@ static int online_memory_block(struct me */ int __ref add_memory_resource(int nid, struct resource *res) { - struct mhp_params params = {}; + struct mhp_params params = { .pgprot = PAGE_KERNEL }; u64 start, size; bool new_node = false; int ret; --- a/mm/memremap.c~mm-memory_hotplug-add-pgprot_t-to-mhp_params +++ a/mm/memremap.c @@ -189,8 +189,8 @@ void *memremap_pages(struct dev_pagemap * We do not want any optional features only our own memmap */ .altmap = pgmap_altmap(pgmap), + .pgprot = PAGE_KERNEL, }; - pgprot_t pgprot = PAGE_KERNEL; int error, is_ram; bool need_devmap_managed = true; @@ -282,8 +282,8 @@ void *memremap_pages(struct dev_pagemap if (nid < 0) nid = numa_mem_id(); - error = track_pfn_remap(NULL, &pgprot, PHYS_PFN(res->start), 0, - resource_size(res)); + error = track_pfn_remap(NULL, ¶ms.pgprot, PHYS_PFN(res->start), + 0, resource_size(res)); if (error) goto err_pfn_remap;