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Wysocki" , nathanl@linux.ibm.com, cheloha@linux.ibm.com, Tony Luck , Fenghua Yu , linux-ia64@vger.kernel.org, linux-kernel@vger.kernel.org, stable@vger.kernel.org, Michal Hocko References: <20200914165042.96218-1-ldufour@linux.ibm.com> <20200914165042.96218-4-ldufour@linux.ibm.com> From: David Hildenbrand Autocrypt: addr=david@redhat.com; prefer-encrypt=mutual; keydata= mQINBFXLn5EBEAC+zYvAFJxCBY9Tr1xZgcESmxVNI/0ffzE/ZQOiHJl6mGkmA1R7/uUpiCjJ dBrn+lhhOYjjNefFQou6478faXE6o2AhmebqT4KiQoUQFV4R7y1KMEKoSyy8hQaK1umALTdL QZLQMzNE74ap+GDK0wnacPQFpcG1AE9RMq3aeErY5tujekBS32jfC/7AnH7I0v1v1TbbK3Gp XNeiN4QroO+5qaSr0ID2sz5jtBLRb15RMre27E1ImpaIv2Jw8NJgW0k/D1RyKCwaTsgRdwuK Kx/Y91XuSBdz0uOyU/S8kM1+ag0wvsGlpBVxRR/xw/E8M7TEwuCZQArqqTCmkG6HGcXFT0V9 PXFNNgV5jXMQRwU0O/ztJIQqsE5LsUomE//bLwzj9IVsaQpKDqW6TAPjcdBDPLHvriq7kGjt WhVhdl0qEYB8lkBEU7V2Yb+SYhmhpDrti9Fq1EsmhiHSkxJcGREoMK/63r9WLZYI3+4W2rAc UucZa4OT27U5ZISjNg3Ev0rxU5UH2/pT4wJCfxwocmqaRr6UYmrtZmND89X0KigoFD/XSeVv jwBRNjPAubK9/k5NoRrYqztM9W6sJqrH8+UWZ1Idd/DdmogJh0gNC0+N42Za9yBRURfIdKSb B3JfpUqcWwE7vUaYrHG1nw54pLUoPG6sAA7Mehl3nd4pZUALHwARAQABtCREYXZpZCBIaWxk ZW5icmFuZCA8ZGF2aWRAcmVkaGF0LmNvbT6JAlgEEwEIAEICGwMGCwkIBwMCBhUIAgkKCwQW AgMBAh4BAheAAhkBFiEEG9nKrXNcTDpGDfzKTd4Q9wD/g1oFAl8Ox4kFCRKpKXgACgkQTd4Q 9wD/g1oHcA//a6Tj7SBNjFNM1iNhWUo1lxAja0lpSodSnB2g4FCZ4R61SBR4l/psBL73xktp rDHrx4aSpwkRP6Epu6mLvhlfjmkRG4OynJ5HG1gfv7RJJfnUdUM1z5kdS8JBrOhMJS2c/gPf wv1TGRq2XdMPnfY2o0CxRqpcLkx4vBODvJGl2mQyJF/gPepdDfcT8/PY9BJ7FL6Hrq1gnAo4 3Iv9qV0JiT2wmZciNyYQhmA1V6dyTRiQ4YAc31zOo2IM+xisPzeSHgw3ONY/XhYvfZ9r7W1l pNQdc2G+o4Di9NPFHQQhDw3YTRR1opJaTlRDzxYxzU6ZnUUBghxt9cwUWTpfCktkMZiPSDGd KgQBjnweV2jw9UOTxjb4LXqDjmSNkjDdQUOU69jGMUXgihvo4zhYcMX8F5gWdRtMR7DzW/YE BgVcyxNkMIXoY1aYj6npHYiNQesQlqjU6azjbH70/SXKM5tNRplgW8TNprMDuntdvV9wNkFs 9TyM02V5aWxFfI42+aivc4KEw69SE9KXwC7FSf5wXzuTot97N9Phj/Z3+jx443jo2NR34XgF 89cct7wJMjOF7bBefo0fPPZQuIma0Zym71cP61OP/i11ahNye6HGKfxGCOcs5wW9kRQEk8P9 M/k2wt3mt/fCQnuP/mWutNPt95w9wSsUyATLmtNrwccz63W5Ag0EVcufkQEQAOfX3n0g0fZz Bgm/S2zF/kxQKCEKP8ID+Vz8sy2GpDvveBq4H2Y34XWsT1zLJdvqPI4af4ZSMxuerWjXbVWb T6d4odQIG0fKx4F8NccDqbgHeZRNajXeeJ3R7gAzvWvQNLz4piHrO/B4tf8svmRBL0ZB5P5A 2uhdwLU3NZuK22zpNn4is87BPWF8HhY0L5fafgDMOqnf4guJVJPYNPhUFzXUbPqOKOkL8ojk CXxkOFHAbjstSK5Ca3fKquY3rdX3DNo+EL7FvAiw1mUtS+5GeYE+RMnDCsVFm/C7kY8c2d0G NWkB9pJM5+mnIoFNxy7YBcldYATVeOHoY4LyaUWNnAvFYWp08dHWfZo9WCiJMuTfgtH9tc75 7QanMVdPt6fDK8UUXIBLQ2TWr/sQKE9xtFuEmoQGlE1l6bGaDnnMLcYu+Asp3kDT0w4zYGsx 5r6XQVRH4+5N6eHZiaeYtFOujp5n+pjBaQK7wUUjDilPQ5QMzIuCL4YjVoylWiBNknvQWBXS lQCWmavOT9sttGQXdPCC5ynI+1ymZC1ORZKANLnRAb0NH/UCzcsstw2TAkFnMEbo9Zu9w7Kv AxBQXWeXhJI9XQssfrf4Gusdqx8nPEpfOqCtbbwJMATbHyqLt7/oz/5deGuwxgb65pWIzufa N7eop7uh+6bezi+rugUI+w6DABEBAAGJAjwEGAEIACYCGwwWIQQb2cqtc1xMOkYN/MpN3hD3 AP+DWgUCXw7HsgUJEqkpoQAKCRBN3hD3AP+DWrrpD/4qS3dyVRxDcDHIlmguXjC1Q5tZTwNB boaBTPHSy/Nksu0eY7x6HfQJ3xajVH32Ms6t1trDQmPx2iP5+7iDsb7OKAb5eOS8h+BEBDeq 3ecsQDv0fFJOA9ag5O3LLNk+3x3q7e0uo06XMaY7UHS341ozXUUI7wC7iKfoUTv03iO9El5f XpNMx/YrIMduZ2+nd9Di7o5+KIwlb2mAB9sTNHdMrXesX8eBL6T9b+MZJk+mZuPxKNVfEQMQ a5SxUEADIPQTPNvBewdeI80yeOCrN+Zzwy/Mrx9EPeu59Y5vSJOx/z6OUImD/GhX7Xvkt3kq Er5KTrJz3++B6SH9pum9PuoE/k+nntJkNMmQpR4MCBaV/J9gIOPGodDKnjdng+mXliF3Ptu6 3oxc2RCyGzTlxyMwuc2U5Q7KtUNTdDe8T0uE+9b8BLMVQDDfJjqY0VVqSUwImzTDLX9S4g/8 kC4HRcclk8hpyhY2jKGluZO0awwTIMgVEzmTyBphDg/Gx7dZU1Xf8HFuE+UZ5UDHDTnwgv7E th6RC9+WrhDNspZ9fJjKWRbveQgUFCpe1sa77LAw+XFrKmBHXp9ZVIe90RMe2tRL06BGiRZr jPrnvUsUUsjRoRNJjKKA/REq+sAnhkNPPZ/NNMjaZ5b8Tovi8C0tmxiCHaQYqj7G2rgnT0kt WNyWQQ== Organization: Red Hat GmbH Message-ID: Date: Tue, 15 Sep 2020 09:23:20 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.11.0 MIME-Version: 1.0 In-Reply-To: <20200914165042.96218-4-ldufour@linux.ibm.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-Rspamd-Queue-Id: DAE978008B14 X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam04 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: On 14.09.20 18:50, Laurent Dufour wrote: > At boot time, or when doing memory hot-add operations, if the links in > sysfs can't be created, the system is still able to run, so just report the > error in the kernel log rather than BUG_ON and potentially make system > unusable because the callpath can be called with locks held. > > Since the number of memory blocks managed could be high, the messages are > rate limited. > > As a consequence, link_mem_sections() has no status to report anymore. > > Signed-off-by: Laurent Dufour > Acked-by: Michal Hocko > Cc: David Hildenbrand > Cc: Greg Kroah-Hartman > --- > drivers/base/node.c | 33 +++++++++++++++++++++------------ > include/linux/node.h | 16 +++++++--------- > mm/memory_hotplug.c | 5 ++--- > 3 files changed, 30 insertions(+), 24 deletions(-) > > diff --git a/drivers/base/node.c b/drivers/base/node.c > index 01ee73c9d675..249b2ba6dc81 100644 > --- a/drivers/base/node.c > +++ b/drivers/base/node.c > @@ -761,8 +761,8 @@ static int __ref get_nid_for_pfn(unsigned long pfn) > return pfn_to_nid(pfn); > } > > -static int do_register_memory_block_under_node(int nid, > - struct memory_block *mem_blk) > +static void do_register_memory_block_under_node(int nid, > + struct memory_block *mem_blk) > { > int ret; > > @@ -775,12 +775,19 @@ static int do_register_memory_block_under_node(int nid, > ret = sysfs_create_link_nowarn(&node_devices[nid]->dev.kobj, > &mem_blk->dev.kobj, > kobject_name(&mem_blk->dev.kobj)); > - if (ret) > - return ret; > + if (ret && ret != -EEXIST) > + dev_err_ratelimited(&node_devices[nid]->dev, > + "can't create link to %s in sysfs (%d)\n", > + kobject_name(&mem_blk->dev.kobj), ret); > > - return sysfs_create_link_nowarn(&mem_blk->dev.kobj, > + ret = sysfs_create_link_nowarn(&mem_blk->dev.kobj, > &node_devices[nid]->dev.kobj, > kobject_name(&node_devices[nid]->dev.kobj)); > + if (ret && ret != -EEXIST) > + dev_err_ratelimited(&mem_blk->dev, > + "can't create link to %s in sysfs (%d)\n", > + kobject_name(&node_devices[nid]->dev.kobj), > + ret); > } > > /* register memory section under specified node if it spans that node */ > @@ -817,7 +824,8 @@ static int register_mem_block_under_node_early(struct memory_block *mem_blk, > continue; > > /* The memory block is registered to the first matching node */ > - return do_register_memory_block_under_node(nid, mem_blk); > + do_register_memory_block_under_node(nid, mem_blk); > + return 0; > } > /* mem section does not span the specified node */ > return 0; > @@ -832,7 +840,8 @@ static int register_mem_block_under_node_hotplug(struct memory_block *mem_blk, > { > int nid = *(int *)arg; > > - return do_register_memory_block_under_node(nid, mem_blk); > + do_register_memory_block_under_node(nid, mem_blk); > + return 0; > } > > /* > @@ -850,8 +859,8 @@ void unregister_memory_block_under_nodes(struct memory_block *mem_blk) > kobject_name(&node_devices[mem_blk->nid]->dev.kobj)); > } > > -int link_mem_sections(int nid, unsigned long start_pfn, unsigned long end_pfn, > - enum meminit_context context) > +void link_mem_sections(int nid, unsigned long start_pfn, unsigned long end_pfn, > + enum meminit_context context) > { > walk_memory_blocks_func_t func; > > @@ -860,9 +869,9 @@ int link_mem_sections(int nid, unsigned long start_pfn, unsigned long end_pfn, > else > func = register_mem_block_under_node_early; > > - return walk_memory_blocks(PFN_PHYS(start_pfn), > - PFN_PHYS(end_pfn - start_pfn), (void *)&nid, > - func); > + walk_memory_blocks(PFN_PHYS(start_pfn), PFN_PHYS(end_pfn - start_pfn), > + (void *)&nid, func); > + return; > } > > #ifdef CONFIG_HUGETLBFS > diff --git a/include/linux/node.h b/include/linux/node.h > index 014ba3ab2efd..8e5a29897936 100644 > --- a/include/linux/node.h > +++ b/include/linux/node.h > @@ -99,15 +99,14 @@ extern struct node *node_devices[]; > typedef void (*node_registration_func_t)(struct node *); > > #if defined(CONFIG_MEMORY_HOTPLUG_SPARSE) && defined(CONFIG_NUMA) > -int link_mem_sections(int nid, unsigned long start_pfn, > - unsigned long end_pfn, > - enum meminit_context context); > +void link_mem_sections(int nid, unsigned long start_pfn, > + unsigned long end_pfn, > + enum meminit_context context); > #else > -static inline int link_mem_sections(int nid, unsigned long start_pfn, > - unsigned long end_pfn, > - enum meminit_context context) > +static inline void link_mem_sections(int nid, unsigned long start_pfn, > + unsigned long end_pfn, > + enum meminit_context context) > { > - return 0; > } > #endif > > @@ -130,8 +129,7 @@ static inline int register_one_node(int nid) > if (error) > return error; > /* link memory sections under this node */ > - error = link_mem_sections(nid, start_pfn, end_pfn, > - MEMINIT_EARLY); > + link_mem_sections(nid, start_pfn, end_pfn, MEMINIT_EARLY); > } > > return error; > diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c > index 03df20078827..01e01a530d38 100644 > --- a/mm/memory_hotplug.c > +++ b/mm/memory_hotplug.c > @@ -1080,9 +1080,8 @@ int __ref add_memory_resource(int nid, struct resource *res) > } > > /* link memory sections under this node.*/ > - ret = link_mem_sections(nid, PFN_DOWN(start), PFN_UP(start + size - 1), > - MEMINIT_HOTPLUG); > - BUG_ON(ret); > + link_mem_sections(nid, PFN_DOWN(start), PFN_UP(start + size - 1), > + MEMINIT_HOTPLUG); > > /* create new memmap entry */ > if (!strcmp(res->name, "System RAM")) > I just remember that I still have some cleanup patches lying around that rework the whole node onlining on the add_memory() path, being able to fail in a nice way rather than ignoring errors. Anyhow, this is good enough for now Acked-by: David Hildenbrand -- Thanks, David / dhildenb