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Peter Anvin" , "Mike Rapoport (Microsoft)" , Jason Gunthorpe , Lu Baolu , Andrew Morton , Lance Yang Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, stable@vger.kernel.org References: <20260429-vmemmap-v2-1-8dfcacffd877@kernel.org> From: "David Hildenbrand (Arm)" Content-Language: en-US Autocrypt: addr=david@kernel.org; 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 B3JfpUqcWwE7vUaYrHG1nw54pLUoPG6sAA7Mehl3nd4pZUALHwARAQABzS5EYXZpZCBIaWxk ZW5icmFuZCAoQ3VycmVudCkgPGRhdmlkQGtlcm5lbC5vcmc+wsGQBBMBCAA6AhsDBQkmWAik AgsJBBUKCQgCFgICHgUCF4AWIQQb2cqtc1xMOkYN/MpN3hD3AP+DWgUCaYJt/AIZAQAKCRBN 3hD3AP+DWriiD/9BLGEKG+N8L2AXhikJg6YmXom9ytRwPqDgpHpVg2xdhopoWdMRXjzOrIKD g4LSnFaKneQD0hZhoArEeamG5tyo32xoRsPwkbpIzL0OKSZ8G6mVbFGpjmyDLQCAxteXCLXz ZI0VbsuJKelYnKcXWOIndOrNRvE5eoOfTt2XfBnAapxMYY2IsV+qaUXlO63GgfIOg8RBaj7x 3NxkI3rV0SHhI4GU9K6jCvGghxeS1QX6L/XI9mfAYaIwGy5B68kF26piAVYv/QZDEVIpo3t7 /fjSpxKT8plJH6rhhR0epy8dWRHk3qT5tk2P85twasdloWtkMZ7FsCJRKWscm1BLpsDn6EQ4 jeMHECiY9kGKKi8dQpv3FRyo2QApZ49NNDbwcR0ZndK0XFo15iH708H5Qja/8TuXCwnPWAcJ DQoNIDFyaxe26Rx3ZwUkRALa3iPcVjE0//TrQ4KnFf+lMBSrS33xDDBfevW9+Dk6IISmDH1R HFq2jpkN+FX/PE8eVhV68B2DsAPZ5rUwyCKUXPTJ/irrCCmAAb5Jpv11S7hUSpqtM/6oVESC 3z/7CzrVtRODzLtNgV4r5EI+wAv/3PgJLlMwgJM90Fb3CB2IgbxhjvmB1WNdvXACVydx55V7 LPPKodSTF29rlnQAf9HLgCphuuSrrPn5VQDaYZl4N/7zc2wcWM7BTQRVy5+RARAA59fefSDR 9nMGCb9LbMX+TFAoIQo/wgP5XPyzLYakO+94GrgfZjfhdaxPXMsl2+o8jhp/hlIzG56taNdt VZtPp3ih1AgbR8rHgXw1xwOpuAd5lE1qNd54ndHuADO9a9A0vPimIes78Hi1/yy+ZEEvRkHk /kDa6F3AtTc1m4rbbOk2fiKzzsE9YXweFjQvl9p+AMw6qd/iC4lUk9g0+FQXNdRs+o4o6Qvy iOQJfGQ4UcBuOy1IrkJrd8qq5jet1fcM2j4QvsW8CLDWZS1L7kZ5gT5EycMKxUWb8LuRjxzZ 3QY1aQH2kkzn6acigU3HLtgFyV1gBNV44ehjgvJpRY2cC8VhanTx0dZ9mj1YKIky5N+C0f21 zvntBqcxV0+3p8MrxRRcgEtDZNav+xAoT3G0W4SahAaUTWXpsZoOecwtxi74CyneQNPTDjNg azHmvpdBVEfj7k3p4dmJp5i0U66Onmf6mMFpArvBRSMOKU9DlAzMi4IvhiNWjKVaIE2Se9BY FdKVAJaZq85P2y20ZBd08ILnKcj7XKZkLU5FkoA0udEBvQ0f9QLNyyy3DZMCQWcwRuj1m73D sq8DEFBdZ5eEkj1dCyx+t/ga6x2rHyc8Sl86oK1tvAkwBNsfKou3v+jP/l14a7DGBvrmlYjO 59o3t6inu6H7pt7OL6u6BQj7DoMAEQEAAcLBfAQYAQgAJgIbDBYhBBvZyq1zXEw6Rg38yk3e EPcA/4NaBQJonNqrBQkmWAihAAoJEE3eEPcA/4NaKtMQALAJ8PzprBEXbXcEXwDKQu+P/vts IfUb1UNMfMV76BicGa5NCZnJNQASDP/+bFg6O3gx5NbhHHPeaWz/VxlOmYHokHodOvtL0WCC 8A5PEP8tOk6029Z+J+xUcMrJClNVFpzVvOpb1lCbhjwAV465Hy+NUSbbUiRxdzNQtLtgZzOV Zw7jxUCs4UUZLQTCuBpFgb15bBxYZ/BL9MbzxPxvfUQIPbnzQMcqtpUs21CMK2PdfCh5c4gS sDci6D5/ZIBw94UQWmGpM/O1ilGXde2ZzzGYl64glmccD8e87OnEgKnH3FbnJnT4iJchtSvx yJNi1+t0+qDti4m88+/9IuPqCKb6Stl+s2dnLtJNrjXBGJtsQG/sRpqsJz5x1/2nPJSRMsx9 5YfqbdrJSOFXDzZ8/r82HgQEtUvlSXNaXCa95ez0UkOG7+bDm2b3s0XahBQeLVCH0mw3RAQg r7xDAYKIrAwfHHmMTnBQDPJwVqxJjVNr7yBic4yfzVWGCGNE4DnOW0vcIeoyhy9vnIa3w1uZ 3iyY2Nsd7JxfKu1PRhCGwXzRw5TlfEsoRI7V9A8isUCoqE2Dzh3FvYHVeX4Us+bRL/oqareJ CIFqgYMyvHj7Q06kTKmauOe4Nf0l0qEkIuIzfoLJ3qr5UyXc2hLtWyT9Ir+lYlX9efqh7mOY qIws/H2t In-Reply-To: <20260429-vmemmap-v2-1-8dfcacffd877@kernel.org> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: B08311C0005 X-Rspam-User: X-Stat-Signature: zx6nerya4i6ffhf5kpxcd914jqbq3gz3 X-HE-Tag: 1778231973-8673 X-HE-Meta: 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 k2TCd0lV +gDhFVNmiV3XbzZYmQI8fTCdMkXz5GyLpJA0ixL6sxOt/ak6G1QWQTLUr907FJfDUN36A4JNL298dIG2HCgx9dOri1zfivrvnNF2T6j9RUdcXnaYT2nD4zzj9SnFipi0nb3WvtvyD1+O7Zbv+lUoAqQK0Wqu0vif4xqHuNtFuimF8x8JG0F4ny5TxfukMsVU/ZTMOre2NWBsjBrCpjR7DjXCFmF3ecLUTZ25cJeeChUjwq8YVIorvLqvZ6DDe8dHAilr8BGrlq1az7ljNmUMGt3RIDA== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 4/29/26 12:49, David Hildenbrand (Arm) wrote: > In commit bf9e4e30f353 ("x86/mm: use pagetable_free()"), we switched > from freeing non-boot page tables through __free_pages() to > pagetable_free(). > > However, the function is also called to free vmemmap pages. > > Given that vmemmap pages are not page tables, already the page_ptdesc(page) > is wrong. But worse, pagetable_free() calls > > __free_pages(page, compound_order(page)); > > As vmemmap pages are not compound pages (see vmemmap_alloc_block()) -- > except for HVO, which doesn't apply here -- we will only free the first > page when freeing a PMD-sized vmemmap page, leaking the other ones. > > Fix it by properly decoupling pagetable and vmemmap freeing. > free_pagetable() no longer has to mess with SECTION_INFO, as only the > vmemmap is marked like that in register_page_bootmem_memmap(). > > The indentation in remove_pmd_table() is messed up, let's fix that > while touching it. > > Note that we'll try to get rid of that bootmem info handling soon. For > now, we'll handle it similar to free_pagetable(), just avoiding the > ifdef. > > Tested-by: Lance Yang > Acked-by: Mike Rapoport (Microsoft) > Fixes: bf9e4e30f353 ("x86/mm: use pagetable_free()") > Cc: stable@vger.kernel.org > Signed-off-by: David Hildenbrand (Arm) > --- > Reproduced and tested with a simple VM with a virtio-mem device, > repeatedly adding and removing memory. > > Found by code inspection while working on bootmem_info removal. > --- @x86 maintainers, do you want to take this through your tree or should we merge this through the MM tree? I have another MM series coming up that will touch this code (no fixes, though). -- Cheers, David