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Peter Anvin" References: <20260527143643.GO31091@soohrt.org> From: Dave Hansen Content-Language: en-US Autocrypt: addr=dave.hansen@intel.com; keydata= xsFNBE6HMP0BEADIMA3XYkQfF3dwHlj58Yjsc4E5y5G67cfbt8dvaUq2fx1lR0K9h1bOI6fC oAiUXvGAOxPDsB/P6UEOISPpLl5IuYsSwAeZGkdQ5g6m1xq7AlDJQZddhr/1DC/nMVa/2BoY 2UnKuZuSBu7lgOE193+7Uks3416N2hTkyKUSNkduyoZ9F5twiBhxPJwPtn/wnch6n5RsoXsb ygOEDxLEsSk/7eyFycjE+btUtAWZtx+HseyaGfqkZK0Z9bT1lsaHecmB203xShwCPT49Blxz VOab8668QpaEOdLGhtvrVYVK7x4skyT3nGWcgDCl5/Vp3TWA4K+IofwvXzX2ON/Mj7aQwf5W iC+3nWC7q0uxKwwsddJ0Nu+dpA/UORQWa1NiAftEoSpk5+nUUi0WE+5DRm0H+TXKBWMGNCFn c6+EKg5zQaa8KqymHcOrSXNPmzJuXvDQ8uj2J8XuzCZfK4uy1+YdIr0yyEMI7mdh4KX50LO1 pmowEqDh7dLShTOif/7UtQYrzYq9cPnjU2ZW4qd5Qz2joSGTG9eCXLz5PRe5SqHxv6ljk8mb ApNuY7bOXO/A7T2j5RwXIlcmssqIjBcxsRRoIbpCwWWGjkYjzYCjgsNFL6rt4OL11OUF37wL QcTl7fbCGv53KfKPdYD5hcbguLKi/aCccJK18ZwNjFhqr4MliQARAQABzUVEYXZpZCBDaHJp c3RvcGhlciBIYW5zZW4gKEludGVsIFdvcmsgQWRkcmVzcykgPGRhdmUuaGFuc2VuQGludGVs LmNvbT7CwXgEEwECACIFAlQ+9J0CGwMGCwkIBwMCBhUIAgkKCwQWAgMBAh4BAheAAAoJEGg1 lTBwyZKwLZUP/0dnbhDc229u2u6WtK1s1cSd9WsflGXGagkR6liJ4um3XCfYWDHvIdkHYC1t MNcVHFBwmQkawxsYvgO8kXT3SaFZe4ISfB4K4CL2qp4JO+nJdlFUbZI7cz/Td9z8nHjMcWYF IQuTsWOLs/LBMTs+ANumibtw6UkiGVD3dfHJAOPNApjVr+M0P/lVmTeP8w0uVcd2syiaU5jB aht9CYATn+ytFGWZnBEEQFnqcibIaOrmoBLu2b3fKJEd8Jp7NHDSIdrvrMjYynmc6sZKUqH2 I1qOevaa8jUg7wlLJAWGfIqnu85kkqrVOkbNbk4TPub7VOqA6qG5GCNEIv6ZY7HLYd/vAkVY E8Plzq/NwLAuOWxvGrOl7OPuwVeR4hBDfcrNb990MFPpjGgACzAZyjdmYoMu8j3/MAEW4P0z F5+EYJAOZ+z212y1pchNNauehORXgjrNKsZwxwKpPY9qb84E3O9KYpwfATsqOoQ6tTgr+1BR CCwP712H+E9U5HJ0iibN/CDZFVPL1bRerHziuwuQuvE0qWg0+0SChFe9oq0KAwEkVs6ZDMB2 P16MieEEQ6StQRlvy2YBv80L1TMl3T90Bo1UUn6ARXEpcbFE0/aORH/jEXcRteb+vuik5UGY 5TsyLYdPur3TXm7XDBdmmyQVJjnJKYK9AQxj95KlXLVO38lczsFNBFRjzmoBEACyAxbvUEhd GDGNg0JhDdezyTdN8C9BFsdxyTLnSH31NRiyp1QtuxvcqGZjb2trDVuCbIzRrgMZLVgo3upr MIOx1CXEgmn23Zhh0EpdVHM8IKx9Z7V0r+rrpRWFE8/wQZngKYVi49PGoZj50ZEifEJ5qn/H Nsp2+Y+bTUjDdgWMATg9DiFMyv8fvoqgNsNyrrZTnSgoLzdxr89FGHZCoSoAK8gfgFHuO54B lI8QOfPDG9WDPJ66HCodjTlBEr/Cwq6GruxS5i2Y33YVqxvFvDa1tUtl+iJ2SWKS9kCai2DR 3BwVONJEYSDQaven/EHMlY1q8Vln3lGPsS11vSUK3QcNJjmrgYxH5KsVsf6PNRj9mp8Z1kIG qjRx08+nnyStWC0gZH6NrYyS9rpqH3j+hA2WcI7De51L4Rv9pFwzp161mvtc6eC/GxaiUGuH BNAVP0PY0fqvIC68p3rLIAW3f97uv4ce2RSQ7LbsPsimOeCo/5vgS6YQsj83E+AipPr09Caj 0hloj+hFoqiticNpmsxdWKoOsV0PftcQvBCCYuhKbZV9s5hjt9qn8CE86A5g5KqDf83Fxqm/ vXKgHNFHE5zgXGZnrmaf6resQzbvJHO0Fb0CcIohzrpPaL3YepcLDoCCgElGMGQjdCcSQ+Ci FCRl0Bvyj1YZUql+ZkptgGjikQARAQABwsFfBBgBAgAJBQJUY85qAhsMAAoJEGg1lTBwyZKw l4IQAIKHs/9po4spZDFyfDjunimEhVHqlUt7ggR1Hsl/tkvTSze8pI1P6dGp2XW6AnH1iayn yRcoyT0ZJ+Zmm4xAH1zqKjWplzqdb/dO28qk0bPso8+1oPO8oDhLm1+tY+cOvufXkBTm+whm +AyNTjaCRt6aSMnA/QHVGSJ8grrTJCoACVNhnXg/R0g90g8iV8Q+IBZyDkG0tBThaDdw1B2l asInUTeb9EiVfL/Zjdg5VWiF9LL7iS+9hTeVdR09vThQ/DhVbCNxVk+DtyBHsjOKifrVsYep WpRGBIAu3bK8eXtyvrw1igWTNs2wazJ71+0z2jMzbclKAyRHKU9JdN6Hkkgr2nPb561yjcB8 sIq1pFXKyO+nKy6SZYxOvHxCcjk2fkw6UmPU6/j/nQlj2lfOAgNVKuDLothIxzi8pndB8Jju KktE5HJqUUMXePkAYIxEQ0mMc8Po7tuXdejgPMwgP7x65xtfEqI0RuzbUioFltsp1jUaRwQZ MTsCeQDdjpgHsj+P2ZDeEKCbma4m6Ez/YWs4+zDm1X8uZDkZcfQlD9NldbKDJEXLIjYWo1PH hYepSffIWPyvBMBTW2W5FRjJ4vLRrJSUoEfJuPQ3vW9Y73foyo/qFoURHO48AinGPZ7PC7TF vUaNOTjKedrqHkaOcqB185ahG2had0xnFsDPlx5y In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspam-User: X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: 7775840005 X-Stat-Signature: ippbcyag1pzga18seg8zihpzgmm9qww4 X-HE-Tag: 1779915885-193286 X-HE-Meta: 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 4POernji +k20SQX7G2lhOPHm4O82FrkC58MRE9qtRJV0YGO0ZNNBmkp6qXeKR6IeHO8L1LgLJUCWBtJWtsbLyTsv7cO92w4HU6b0HXH4hwyWxoYCv7coYX8E12lBivdqcJTt72g/Kzz5fi5M7vW8yQ+ldYWc4bga0yfP4yhCzb3DPmHjsLfga4Z6pfgQ1ALLacpaBya8D3/X1VOdUrxaZrQmcz1tmElr8/A0daNTWn5YuJdQEXqLPZL2Tj3uFJFKzpQ== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 5/27/26 11:28, Oscar Salvador (SUSE) wrote: > if (filp) { > info.align_mask = get_align_mask(filp); > - info.align_offset += get_align_bits(); > + /* > + * Hugepages must remain hugepage-aligned, so skip adding an offset > + * in case we enabled 'align_va_addr'. > + */ > + if (!is_file_hugepages(filp)) > + info.align_offset += get_align_bits(); > } That's a good hack to show the scope of the problem. But I'd really rather this be dealt with in the arch-independent code, not by adding hugetlb hacks to arch code. It isn't even clear to me what exactly goes wrong when you set a tiny ->align_offset and have a larger ->align_mask. Shouldn't the tiny offset just get masked off? gap += (info->align_offset - gap) & info->align_mask; I spent a whole five seconds looking at it, but something seems to be missing from the problem description.