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Peter Anvin" , Andrey Konovalov References: <20260610175651.647515-1-ihor.solodrai@linux.dev> <326b85af-c41a-4387-90a0-60720111934d@linux.dev> <20260618170913.GBajQmOQyOiBLqopUl@fat_crate.local> 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: <20260618170913.GBajQmOQyOiBLqopUl@fat_crate.local> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspam-User: X-Rspamd-Server: rspam09 X-Rspamd-Queue-Id: C7EA9140009 X-Stat-Signature: gmibbt1ou4k31zfmpmqtiy7r8jh1494z X-HE-Tag: 1781806332-588417 X-HE-Meta: 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 vsXMaSqh PURTOjrfVew6wiuFT8aFplYRArFFet8uZIhfiUjCoS4oZGQMnvEjkO6EpDxurnqSrlHsPcpnwWFseJ7JXwRZUxAy32XRE1T8qCN0SeYczQ/y6RNQXD7WWNgaIoBUGw+06pd8UBnbN39yXuxYedeO2e8kRpEuIHSP0I2RWvaRwya6l+pHR+h7nUqsdgUgLTnzkP0Pw6fkqHG7Mjklcoe7wl2Mpa4hi6sGd0+KigRvwSm17PrfHeCQN2zEEPvtFR8wtMYCZRa/dbmTGFgxfwHskNQUoU4CiAo1kWjp3H2GWpxMRWUQ= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 6/18/26 10:09, Borislav Petkov wrote: > On Wed, Jun 17, 2026 at 03:13:33PM -0700, Ihor Solodrai wrote: >> So my question to maintainers is what approach seems best? > The CPUID stuff is being rewritten currently and it should address your issue > too. If not, then we need to rewrite it better. > > Can you reproduce with this set applied ontop: > > https://lore.kernel.org/r/20260528153923.403473-1-darwi@linutronix.de Thinking about this a bit more... If Ahmed's series does fix this, I think it will be accidental. It still uses identify_cpu() and also does a memset() of the new c->cpuid structure in addition to the old c->x86_capability structure. I'm not knocking Ahmed's series by any means. It just probably won't fix this issue. In a perfect world early_identify_cpu() and identify_cpu() would either get consolidated into one thing. Or at least become two discrete things that initialize two completely disjoint sets of data. That way, identify_cpu() wouldn't memset() anything. Isn't that the _real_ fix? Instead of trying to hide the inconsistency when good data is blown away, we stop blowing it away in the first place?