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[2003:cb:c708:1500:d584:7ad8:d3f7:5539]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-381ed970729sm18722503f8f.15.2024.11.13.08.45.44 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 13 Nov 2024 08:45:44 -0800 (PST) Message-ID: <99a77c9a-68ca-4445-bcbf-4681ca20a482@redhat.com> Date: Wed, 13 Nov 2024 17:45:43 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH stable 5.15] mm/memory: add non-anonymous page check in the copy_present_page() To: Vlastimil Babka , stable@vger.kernel.org Cc: Peter Xu , linux-mm@kvack.org, Yuanzheng Song References: <20241113163118.54834-2-vbabka@suse.cz> From: David Hildenbrand Autocrypt: addr=david@redhat.com; keydata= xsFNBFXLn5EBEAC+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 B3JfpUqcWwE7vUaYrHG1nw54pLUoPG6sAA7Mehl3nd4pZUALHwARAQABzSREYXZpZCBIaWxk ZW5icmFuZCA8ZGF2aWRAcmVkaGF0LmNvbT7CwZgEEwEIAEICGwMGCwkIBwMCBhUIAgkKCwQW 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/mWutNPt95w9wSsUyATLmtNrwccz63XOwU0EVcufkQEQAOfX3n0g0fZz 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+w6DABEBAAHCwXwEGAEIACYCGwwWIQQb2cqtc1xMOkYN/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 In-Reply-To: <20241113163118.54834-2-vbabka@suse.cz> X-Mimecast-Spam-Score: 0 X-Mimecast-MFC-PROC-ID: Ct4oIaA4oXoD_8APisInskHoeqClgAREI3R_HNAUHU8_1731516346 X-Mimecast-Originator: redhat.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 1900840005 X-Stat-Signature: 3jsrk6mzp8uwizabmn49n8wg5sckdgdp X-Rspam-User: X-HE-Tag: 1731516289-870955 X-HE-Meta: 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 wSKSuB2a 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 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: List-Subscribe: List-Unsubscribe: On 13.11.24 17:31, Vlastimil Babka wrote: > From: Yuanzheng Song > > The vma->anon_vma of the child process may be NULL because > the entire vma does not contain anonymous pages. In this > case, a BUG will occur when the copy_present_page() passes > a copy of a non-anonymous page of that vma to the > page_add_new_anon_rmap() to set up new anonymous rmap. > > ------------[ cut here ]------------ > kernel BUG at mm/rmap.c:1052! > Internal error: Oops - BUG: 0 [#1] SMP > Modules linked in: > CPU: 4 PID: 4652 Comm: test Not tainted 5.15.75 #1 > Hardware name: linux,dummy-virt (DT) > pstate: 80000005 (Nzcv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) > pc : __page_set_anon_rmap+0xc0/0xe8 > lr : __page_set_anon_rmap+0xc0/0xe8 > sp : ffff80000e773860 > x29: ffff80000e773860 x28: fffffc13cf006ec0 x27: ffff04f3ccd68000 > x26: ffff04f3c5c33248 x25: 0000000010100073 x24: ffff04f3c53c0a80 > x23: 0000000020000000 x22: 0000000000000001 x21: 0000000020000000 > x20: fffffc13cf006ec0 x19: 0000000000000000 x18: 0000000000000000 > x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000 > x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000000000 > x11: 0000000000000000 x10: 0000000000000000 x9 : ffffdddc5581377c > x8 : 0000000000000000 x7 : 0000000000000011 x6 : ffff2717a8433000 > x5 : ffff80000e773810 x4 : ffffdddc55400000 x3 : 0000000000000000 > x2 : ffffdddc56b20000 x1 : ffff04f3c9a48040 x0 : 0000000000000000 > Call trace: > __page_set_anon_rmap+0xc0/0xe8 > page_add_new_anon_rmap+0x13c/0x200 > copy_pte_range+0x6b8/0x1018 > copy_page_range+0x3a8/0x5e0 > dup_mmap+0x3a0/0x6e8 > dup_mm+0x78/0x140 > copy_process+0x1528/0x1b08 > kernel_clone+0xac/0x610 > __do_sys_clone+0x78/0xb0 > __arm64_sys_clone+0x30/0x40 > invoke_syscall+0x68/0x170 > el0_svc_common.constprop.0+0x80/0x250 > do_el0_svc+0x48/0xb8 > el0_svc+0x48/0x1a8 > el0t_64_sync_handler+0xb0/0xb8 > el0t_64_sync+0x1a0/0x1a4 > Code: 97f899f4 f9400273 17ffffeb 97f899f1 (d4210000) > ---[ end trace dc65e5edd0f362fa ]--- > Kernel panic - not syncing: Oops - BUG: Fatal exception > SMP: stopping secondary CPUs > Kernel Offset: 0x5ddc4d400000 from 0xffff800008000000 > PHYS_OFFSET: 0xfffffb0c80000000 > CPU features: 0x44000cf1,00000806 > Memory Limit: none > ---[ end Kernel panic - not syncing: Oops - BUG: Fatal exception ]--- > > This problem has been fixed by the commit > ("mm/rmap: split page_dup_rmap() into page_dup_file_rmap() > and page_try_dup_anon_rmap()"), but still exists in the > linux-5.15.y branch. > > This patch is not applicable to this version because > of the large version differences. Therefore, fix it by > adding non-anonymous page check in the copy_present_page(). > > Cc: stable@vger.kernel.org > Fixes: 70e806e4e645 ("mm: Do early cow for pinned pages during fork() for ptes") > Signed-off-by: Yuanzheng Song > Signed-off-by: Vlastimil Babka > --- > Hi, this was posted in [1] but seems stable@ was not actually included > in the recipients. > The 5.10 version [2] was applied as 935a8b62021 but 5.15 is missing. > > [1] https://lore.kernel.org/all/20221028075244.3112566-1-songyuanzheng@huawei.com/T/#u > [2] https://lore.kernel.org/all/20221028030705.2840539-1-songyuanzheng@huawei.com/ > > > mm/memory.c | 11 +++++++++++ > 1 file changed, 11 insertions(+) > > diff --git a/mm/memory.c b/mm/memory.c > index 6d058973a97e..4785aecca9a8 100644 > --- a/mm/memory.c > +++ b/mm/memory.c > @@ -903,6 +903,17 @@ copy_present_page(struct vm_area_struct *dst_vma, struct vm_area_struct *src_vma > if (likely(!page_needs_cow_for_dma(src_vma, page))) > return 1; > > + /* > + * The vma->anon_vma of the child process may be NULL > + * because the entire vma does not contain anonymous pages. > + * A BUG will occur when the copy_present_page() passes > + * a copy of a non-anonymous page of that vma to the > + * page_add_new_anon_rmap() to set up new anonymous rmap. > + * Return 1 if the page is not an anonymous page. > + */ > + if (!PageAnon(page)) > + return 1; > + > new_page = *prealloc; > if (!new_page) > return -EAGAIN; Reviewed-by: David Hildenbrand -- Cheers, David / dhildenb