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See http://www.infradead.org/rpr.html X-Rspamd-Queue-Id: CA30D4000F X-Rspam-User: X-Rspamd-Server: rspam04 X-Stat-Signature: aartzeh97uy4ozxpxkjxi7gmx77f5fqw X-HE-Tag: 1684824319-312060 X-HE-Meta: U2FsdGVkX18wXMszTcd5wCv7529SJ9RXVAOteyBhc1sRcsaY0uHxZTYCu5LrZlevOpmXtte2PmrH6dQh3oxkGiUoxiB9kTYG9yEf7p0O+KUSFPKHMKO2/bco3x0BBEeYZDik/C6xT1c4xryXXLLb3vOXJvT+wyCsV1cYfN7exZltOn5naXs+RXMzjSdCqRkOGNKk7wXW0pa1T4YFR7jGIVGHYshDp8HwbXCGG4+wd0zMCr3OiihkfQqmu7elEulW4g190Qh8T2N7MKiD6n9Ejf6NruYunlvbz0q4KGZ32X6s0gfXjhnOVme39zUgdwW+6vjUizpVrmfTNzk2d58zV7lU3pIcXygyj1SquoCryanSOSbtI2eIISiO1/7pb1IbV6dXIp4QNnphfj1vmiZUddyBz+FPv3sQa8D6mgD0/8uxdWtVtkPbiTXvV4kVBJjWVU6QhtNDx8XPv43nmwOO2dIEasX+qgjcfcF2IQ6VmJb2OXULol/szz1M1CaBg38b02vDjRDbN265bg5Gek8fYvpZl2BhrJbsvieZ1CwdwcS0vyOIEK6miDxfBgxNzcLawYp4ZgXeH9GPGsq8GjMphjuFKywCLNNKP8mCSEvJJdBHTT1kFTiYWm4Rkv34hb9uBAAqFuLwy9BuGbuwbzQFMfL0HBhjE3LGG7kQB34JnluvIVKVUr4XmWXlcywjn7MFEpycNHfpI8o04ED/3z+2buJqImkhxTMG4faWAULD/kJkjBIiMCoipxXSKJ8kPipBommbe6lomkReLJav3x+pKQbxVDXD4YzvkDjBaTmWhtAIsneMopMH30zmL6k1jWcop5DnaF7/NzhZZVRyBn8ZXp1Fc3JFCTRoEFxyUPPIo4m/AeHWgdMcIEHSvkkmkcTpl6i7K9ByFc0wDTMIr/QIJVzkl97SYFDylhBeYKL+t0rcaK9MoALJBfFJaTXtaJJK+zBOURE4901CyGyGWfw cPAinRAE etYed3TRAWXlLK3ihmmJePKDbmFuEPZWtC7YGSoyMduK2twTqOsFjmtPsC4x7ebdPRBZ6EkhRq8ZnYz8h3Z4ryJlVOsjJ3ZzljNefOAhVEG+FJDVdm5qZH8bc5drXLmv5+JQ9Z7hZkpYZRW1ROjyHxpwiIjWPh3feyA+32ri/fMvIRRWtpEH7vJlN4pkN7za5KMegX54JsG1UWk1ALCTEhXDQRezVbI0mByXS/acDohV/i9c/OUBIUO67oGSNDqpYsvqjNcw2M2oLHb2DOx98dBemnDfXaUP8DoA1Yv942Jx6Vp14eNybw0VLskd+aStelT3/F3ylZhrzTCeOvlHr4Buq4mr5MJM8piylK7WPKMrMV1CdyCkhLO7AxNRn5BVcLgwMyevp1vLAi2HUuNPoexfNvDJIJjXgQWsSeUGW80oWOyDtmk36OWwZiw== 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: On Mon, May 22, 2023 at 04:37:25PM +1000, Alistair Popple wrote: > This problem was discovered during testing of an ARM SMMU > implementation that does not support broadcast TLB maintenance > (BTM). In this case the SMMU driver uses notifiers to issue TLB > invalidates. For read-only to read-write pte upgrades the SMMU > continually returned a read-only PTE to the device, even though the > CPU had a read-write PTE installed. > > Sending a mmu notifier event to the SMMU driver fixes the problem by > flushing secondary TLB entries. A new notifier event type is added so > drivers may filter out these invalidations if not required. Note a > driver should never upgrade or install a PTE in response to this mmu > notifier event as it is not synchronised against other PTE operations. I don't see these SMMU driver changes anywhere. I.e. you're adding dead code as far as I can tell.