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charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: 6945A120009 X-Stat-Signature: 4w3egmg7ortpi1h1bo7tx1ktnxd9b779 X-Rspam-User: X-HE-Tag: 1758276532-155405 X-HE-Meta: U2FsdGVkX1+qfnWRW1GHxZ1y9OAkFjVcNmVagLYv+i4ML2gOl1+ILe2nrq+LFAdmgLlASazLHBQYWlPOf+DALA8akU/GxQ4VL4ytw+yiIbnXbzclJGSrkcjgHFz8Iqh5JJQ+sv4rZ7BIZIz52gS6OU7Er8uUC1IEOVYxqpUnpJe7mmWt4IZpFvQ2tcCh/pao4VcRx7TFq3G0EMJnJlA52KvZoPavP1IyMC+uv9IQQauDB8IVxtyIn4hR6IJZIrgZFdT3NB02/gIYh3gPXogDpJHJXKObw/7aNvokudHKhsaSG9Etv1SlPrHSZT1SAvV5ErG82Ms1rfEanmlf+FC3y6OzHimLzRKCh/fvXIw9GAu0Un9TNDFNfo2H2W74Fyu9yr8d2eIWU6z6wAduEXvRgiYT+jckhZtbtGwfFtqmccp1vJSlFqdq4f+PUxbtKR5QtFR5B208v/GGV5lqKhtAwIkd3B78ho+rdqPhfouvcKjy9PijOXJ7vG9OEP9wTZXMVkwYENj0AVxOwGb4XXzzYU61GntLw4FkIGpotQ3LXBkQnWJv+sQ1FjTrmUqLV/qzNvNsRrvZgR6Drbi9Z5qHJ2SzSZPwoFkQGTGY4mPu4wo7aQxD2lrk/tkJD6l3ECn6iyPHVUbcHyQGmaot/d57VP8HIBjW6MgZYYuPyj/rrGJuqQV0NNJcD36m/s4tattd0BepwjL/k1DEk6/6MWM4k6E0xhP7Xb6apunIINSXhrmMR0e81YS7mTT8WnmE63VdINAM+8L1QBhtISIMT6VWO8ajt0a4oO7chqXGBiwYac7K+sh9d95YznkFMdYvyVWAzvo83rCH4fc/Zxj5jMvTgFvKr8at32Vs49rJo3ZCHUKlquYaNua2hoZx3EIs2yifjSKCRrjGNOhmdlGS5tKJIQbHNZLesAFQEtRdqTZ/GV3Np/cZ/pJ6o41T9zGoaC9xTYSi6bwy+ZJmurT1kjx R6R/cnG9 VVGhsG0MBxc4VWsaYJIBR9UFa4FULWvF7EI5RICIn4tc4/Hj0dLpviLAsRuKECdXPEM4Hg2oMomMi2n8hGAzasS9HtX0Wcr9LBo/VePUcSu8lQESS/loyrNY9YwzKVcJFxZ6NbkUBo2vwsJ5ngopmj0pLfr4TH/ih5aOjkDKktRRuFA4fIEO8RXcmPmXXjVhod/QxIJeSgeoUslBcO6gqy0QaAyPlAFtdMtH6rYo1HB+H1pwml01EvRRf3F9pn8lnJW/Ky+2EDUJkhy64LNAYZlBJoTJUt7jIxzcrtHaufFENFdtHxLVsc93MhnzDDrWCwNQU 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 18/09/2025 22:10, Will Deacon wrote: > On Wed, 17 Sep 2025 12:02:06 -0700, Yang Shi wrote: >> On systems with BBML2_NOABORT support, it causes the linear map to be mapped >> with large blocks, even when rodata=full, and leads to some nice performance >> improvements. >> >> Ryan tested v7 on an AmpereOne system (a VM with 12G RAM) in all 3 possible >> modes by hacking the BBML2 feature detection code: >> >> [...] > > Applied patches 1 and 3 to arm64 (for-next/mm), thanks! > > [1/5] arm64: Enable permission change on arm64 kernel block mappings > https://git.kernel.org/arm64/c/a660194dd101 > [3/5] arm64: mm: support large block mapping when rodata=full > https://git.kernel.org/arm64/c/a166563e7ec3 > > I also picked up the BBML allow-list addition (second patch) on > for-next/cpufeature. > > The fourth patch ("arm64: mm: split linear mapping if BBML2 unsupported > on secondary CPUs") has some really horrible conflicts. These are partly > due to some of the type cleanups on for-next/mm but I think mainly due > to Kevin's kpti rework that landed after -rc1. Thanks Will, although I'm nervous that without this patch, some platforms might not boot; Wikipedia tells me that there are some Google, Mediatek and Qualcomm SoCs that pair X4 CPUs (which is on the BBML2_NOABORT allow list) with A720 and/or A520 (which are not). See previous mail at [1]. I'd be happy to rebase it if you can let me know the prefered base SHA/tree? [1] https://lore.kernel.org/linux-arm-kernel/11f84d00-8c76-402d-bbad-014a3542992f@arm.com/ Thanks, Ryan > > So I think the best bet might be to leave that one for next time, if > that's ok? > > Cheers,