From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id AB8CAC10F0E for ; Tue, 9 Apr 2019 10:05:55 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 30C8B2083E for ; Tue, 9 Apr 2019 10:05:55 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 30C8B2083E Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 44djbj14xSzDqLM for ; Tue, 9 Apr 2019 20:05:53 +1000 (AEST) Authentication-Results: lists.ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=redhat.com (client-ip=209.132.183.28; helo=mx1.redhat.com; envelope-from=david@redhat.com; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=pass (p=none dis=none) header.from=redhat.com Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 44djWh44xzzDqJR for ; Tue, 9 Apr 2019 20:02:24 +1000 (AEST) Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id DE6FB30018EA; Tue, 9 Apr 2019 10:02:21 +0000 (UTC) Received: from t460s.redhat.com (ovpn-117-49.ams2.redhat.com [10.36.117.49]) by smtp.corp.redhat.com (Postfix) with ESMTP id 67F095D71F; Tue, 9 Apr 2019 10:02:13 +0000 (UTC) From: David Hildenbrand To: linux-mm@kvack.org Subject: [PATCH v1 4/4] mm/memory_hotplug: Make __remove_pages() and arch_remove_memory() never fail Date: Tue, 9 Apr 2019 12:01:48 +0200 Message-Id: <20190409100148.24703-5-david@redhat.com> In-Reply-To: <20190409100148.24703-1-david@redhat.com> References: <20190409100148.24703-1-david@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.46]); Tue, 09 Apr 2019 10:02:22 +0000 (UTC) X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Oscar Salvador , Michal Hocko , linux-ia64@vger.kernel.org, David Hildenbrand , Peter Zijlstra , Dave Hansen , Heiko Carstens , Stefan Agner , Wei Yang , Masahiro Yamada , Rich Felker , Paul Mackerras , "H. Peter Anvin" , Qian Cai , Rob Herring , Yoshinori Sato , linux-sh@vger.kernel.org, x86@kernel.org, Mike Rapoport , Ingo Molnar , Geert Uytterhoeven , Fenghua Yu , Pavel Tatashin , Vasily Gorbik , linux-s390@vger.kernel.org, Nicholas Piggin , Borislav Petkov , Andy Lutomirski , Thomas Gleixner , Joonsoo Kim , Tony Luck , Mathieu Malaterre , linux-kernel@vger.kernel.org, Martin Schwidefsky , Arun KS , Andrew Morton , linuxppc-dev@lists.ozlabs.org, "Kirill A. Shutemov" Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" All callers of arch_remove_memory() ignore errors. And we should really try to remove any errors from the memory removal path. No more errors are reported from __remove_pages(). BUG() in s390x code in case arch_remove_memory() is triggered. We may implement that properly later. WARN in case powerpc code failed to remove the section mapping, which is better than ignoring the error completely right now. Cc: Tony Luck Cc: Fenghua Yu Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: Michael Ellerman Cc: Martin Schwidefsky Cc: Heiko Carstens Cc: Yoshinori Sato Cc: Rich Felker Cc: Dave Hansen Cc: Andy Lutomirski Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Borislav Petkov Cc: "H. Peter Anvin" Cc: x86@kernel.org Cc: Andrew Morton Cc: Michal Hocko Cc: Mike Rapoport Cc: Oscar Salvador Cc: "Kirill A. Shutemov" Cc: Christophe Leroy Cc: Stefan Agner Cc: Nicholas Piggin Cc: Pavel Tatashin Cc: Vasily Gorbik Cc: Arun KS Cc: Geert Uytterhoeven Cc: Masahiro Yamada Cc: Rob Herring Cc: Joonsoo Kim Cc: Wei Yang Cc: Qian Cai Cc: Mathieu Malaterre Cc: linux-ia64@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Cc: linux-sh@vger.kernel.org Cc: linux-s390@vger.kernel.org Signed-off-by: David Hildenbrand --- arch/ia64/mm/init.c | 11 +++-------- arch/powerpc/mm/mem.c | 11 ++++------- arch/s390/mm/init.c | 5 +++-- arch/sh/mm/init.c | 11 +++-------- arch/x86/mm/init_32.c | 5 +++-- arch/x86/mm/init_64.c | 10 +++------- include/linux/memory_hotplug.h | 8 ++++---- mm/memory_hotplug.c | 5 ++--- 8 files changed, 25 insertions(+), 41 deletions(-) diff --git a/arch/ia64/mm/init.c b/arch/ia64/mm/init.c index 379eb1f9adc9..d28e29103bdb 100644 --- a/arch/ia64/mm/init.c +++ b/arch/ia64/mm/init.c @@ -682,20 +682,15 @@ int arch_add_memory(int nid, u64 start, u64 size, } #ifdef CONFIG_MEMORY_HOTREMOVE -int arch_remove_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap) +void arch_remove_memory(int nid, u64 start, u64 size, + struct vmem_altmap *altmap) { unsigned long start_pfn = start >> PAGE_SHIFT; unsigned long nr_pages = size >> PAGE_SHIFT; struct zone *zone; - int ret; zone = page_zone(pfn_to_page(start_pfn)); - ret = __remove_pages(zone, start_pfn, nr_pages, altmap); - if (ret) - pr_warn("%s: Problem encountered in __remove_pages() as" - " ret=%d\n", __func__, ret); - - return ret; + __remove_pages(zone, start_pfn, nr_pages, altmap); } #endif #endif diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c index 76deaa8525db..cc9425fb9056 100644 --- a/arch/powerpc/mm/mem.c +++ b/arch/powerpc/mm/mem.c @@ -131,8 +131,8 @@ int __meminit arch_add_memory(int nid, u64 start, u64 size, } #ifdef CONFIG_MEMORY_HOTREMOVE -int __meminit arch_remove_memory(int nid, u64 start, u64 size, - struct vmem_altmap *altmap) +void __meminit arch_remove_memory(int nid, u64 start, u64 size, + struct vmem_altmap *altmap) { unsigned long start_pfn = start >> PAGE_SHIFT; unsigned long nr_pages = size >> PAGE_SHIFT; @@ -147,14 +147,13 @@ int __meminit arch_remove_memory(int nid, u64 start, u64 size, if (altmap) page += vmem_altmap_offset(altmap); - ret = __remove_pages(page_zone(page), start_pfn, nr_pages, altmap); - if (ret) - return ret; + __remove_pages(page_zone(page), start_pfn, nr_pages, altmap); /* Remove htab bolted mappings for this section of memory */ start = (unsigned long)__va(start); flush_inval_dcache_range(start, start + size); ret = remove_section_mapping(start, start + size); + WARN_ON_ONCE(ret); /* Ensure all vmalloc mappings are flushed in case they also * hit that section of memory @@ -162,8 +161,6 @@ int __meminit arch_remove_memory(int nid, u64 start, u64 size, vm_unmap_aliases(); resize_hpt_for_hotplug(memblock_phys_mem_size()); - - return ret; } #endif #endif /* CONFIG_MEMORY_HOTPLUG */ diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c index f5db961ad792..31b1071315d7 100644 --- a/arch/s390/mm/init.c +++ b/arch/s390/mm/init.c @@ -234,14 +234,15 @@ int arch_add_memory(int nid, u64 start, u64 size, } #ifdef CONFIG_MEMORY_HOTREMOVE -int arch_remove_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap) +void arch_remove_memory(int nid, u64 start, u64 size, + struct vmem_altmap *altmap) { /* * There is no hardware or firmware interface which could trigger a * hot memory remove on s390. So there is nothing that needs to be * implemented. */ - return -EBUSY; + BUG(); } #endif #endif /* CONFIG_MEMORY_HOTPLUG */ diff --git a/arch/sh/mm/init.c b/arch/sh/mm/init.c index 168d3a6b9358..5aeb4d7099a1 100644 --- a/arch/sh/mm/init.c +++ b/arch/sh/mm/init.c @@ -429,20 +429,15 @@ EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid); #endif #ifdef CONFIG_MEMORY_HOTREMOVE -int arch_remove_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap) +void arch_remove_memory(int nid, u64 start, u64 size, + struct vmem_altmap *altmap) { unsigned long start_pfn = PFN_DOWN(start); unsigned long nr_pages = size >> PAGE_SHIFT; struct zone *zone; - int ret; zone = page_zone(pfn_to_page(start_pfn)); - ret = __remove_pages(zone, start_pfn, nr_pages, altmap); - if (unlikely(ret)) - pr_warn("%s: Failed, __remove_pages() == %d\n", __func__, - ret); - - return ret; + __remove_pages(zone, start_pfn, nr_pages, altmap); } #endif #endif /* CONFIG_MEMORY_HOTPLUG */ diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c index 755dbed85531..075e568098f2 100644 --- a/arch/x86/mm/init_32.c +++ b/arch/x86/mm/init_32.c @@ -860,14 +860,15 @@ int arch_add_memory(int nid, u64 start, u64 size, } #ifdef CONFIG_MEMORY_HOTREMOVE -int arch_remove_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap) +void arch_remove_memory(int nid, u64 start, u64 size, + struct vmem_altmap *altmap) { unsigned long start_pfn = start >> PAGE_SHIFT; unsigned long nr_pages = size >> PAGE_SHIFT; struct zone *zone; zone = page_zone(pfn_to_page(start_pfn)); - return __remove_pages(zone, start_pfn, nr_pages, altmap); + __remove_pages(zone, start_pfn, nr_pages, altmap); } #endif #endif diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c index db42c11b48fb..20d14254b686 100644 --- a/arch/x86/mm/init_64.c +++ b/arch/x86/mm/init_64.c @@ -1141,24 +1141,20 @@ kernel_physical_mapping_remove(unsigned long start, unsigned long end) remove_pagetable(start, end, true, NULL); } -int __ref arch_remove_memory(int nid, u64 start, u64 size, - struct vmem_altmap *altmap) +void __ref arch_remove_memory(int nid, u64 start, u64 size, + struct vmem_altmap *altmap) { unsigned long start_pfn = start >> PAGE_SHIFT; unsigned long nr_pages = size >> PAGE_SHIFT; struct page *page = pfn_to_page(start_pfn); struct zone *zone; - int ret; /* With altmap the first mapped page is offset from @start */ if (altmap) page += vmem_altmap_offset(altmap); zone = page_zone(page); - ret = __remove_pages(zone, start_pfn, nr_pages, altmap); - WARN_ON_ONCE(ret); + __remove_pages(zone, start_pfn, nr_pages, altmap); kernel_physical_mapping_remove(start, start + size); - - return ret; } #endif #endif /* CONFIG_MEMORY_HOTPLUG */ diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h index d0a145ffa4fe..9d0efac902ec 100644 --- a/include/linux/memory_hotplug.h +++ b/include/linux/memory_hotplug.h @@ -112,10 +112,10 @@ static inline bool movable_node_is_enabled(void) } #ifdef CONFIG_MEMORY_HOTREMOVE -extern int arch_remove_memory(int nid, u64 start, u64 size, - struct vmem_altmap *altmap); -extern int __remove_pages(struct zone *zone, unsigned long start_pfn, - unsigned long nr_pages, struct vmem_altmap *altmap); +extern void arch_remove_memory(int nid, u64 start, u64 size, + struct vmem_altmap *altmap); +extern void __remove_pages(struct zone *zone, unsigned long start_pfn, + unsigned long nr_pages, struct vmem_altmap *altmap); #endif /* CONFIG_MEMORY_HOTREMOVE */ /* diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index 17a60281c36f..52fef4a81e4c 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -548,8 +548,8 @@ static void __remove_section(struct zone *zone, struct mem_section *ms, * sure that pages are marked reserved and zones are adjust properly by * calling offline_pages(). */ -int __remove_pages(struct zone *zone, unsigned long phys_start_pfn, - unsigned long nr_pages, struct vmem_altmap *altmap) +void __remove_pages(struct zone *zone, unsigned long phys_start_pfn, + unsigned long nr_pages, struct vmem_altmap *altmap) { unsigned long i; unsigned long map_offset = 0; @@ -580,7 +580,6 @@ int __remove_pages(struct zone *zone, unsigned long phys_start_pfn, } set_zone_contiguous(zone); - return 0; } #endif /* CONFIG_MEMORY_HOTREMOVE */ -- 2.17.2