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charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Stat-Signature: mhaumhw78sf4xa6tjcyymd9ftqwtxm73 X-Rspamd-Queue-Id: 9E52AA000A X-Rspam-User: X-Rspamd-Server: rspam05 X-HE-Tag: 1746787436-415221 X-HE-Meta: U2FsdGVkX19WD4L4rNcg6lTJWVcl84i0oJ+1qddh8eFToDznFaG8LyCESUOXwQji9ML0xiWQC1vV0LpCdyWEkxdFpv8zBE2myvtu4SUgHcCEI01Vu07pkCxUMrFCE2zNF1MAdmlr3VVU6rZTlapXYQPrdgM+U12XdmLoOqi2JfIscRg1wyyXqJaa+zBJf0ycHm0BQrB0NnI1X2Y9IYmcnPhbIXcba3/ghwsDeH7F/Kn2jZVCdMHNmtm+E9e7yEj8srdm4HgajCVxhcu2fgv/U7XUxYvQemxUPDVXSajzBq0dxFGQvQ4itQLZkPuD2dtT1Of8urddEjzzT6WCSu40V7LVE3Q0eL8rktlU4trw3G0eEOo5dlxasVY8pd4bAMqMl3ZMGwXgzRqT1PNEZ30tTXLKNjVPF/7XJ4tXguYb8V6coCMZv7SC2mf1S02gyjGMwPyTlbw3jOlKhvx2TgRkguRU4gj7eQOqBmmy2RUltUGutjBKKsTDvo17fS4LzhSZ2uz9c/IIIlJ9RtjBbaYn8RMLSrEZ8eEozBn76W6RP4jnMnLVZHa+bCSQRegsAy5Vz3JnUu9wUeuWyC+Zcl7gBlHoXyW2N/mATz1L23xw9NQQ25AGXtJJWdos7E3x5jQcfmdYNiO0458zVWJkqv2pwn2IiL9JTdn3mvmDk1deVE1Le+gOHDhTvNOsIgmMY+4OtbH67lokuAVaT4kfnOxILggLe4p4BryL/bYDvM4BHx2NrysJuyIX1oS5wS8idta3TF5mJ8rYBpkS4Dx2bEsekOYHDiSKSa9JNsibIU+zKn12p4OOSQKREAhzK5cnV6dfCD5+VUbzoOT2yRfcfnf+uFSBg2UCGXHbGfxFid9HsIt1F/PqDtX5mkL5Is3ViF4WRIxUcLNGlD5eYh+NAqXJPtkpwKG/VNaw2MSjvINlMmKCMpAVKpCDPQ4EPP4vB50WziuiGLARp7VIdquoO6B DR3z2NbP iqdvhqJ8xD03Cv0NyuQdGYvTKPbeHj1Cdq1GoalfH0nDB1Ea06FtfJSzizK5RGzE8fH/fh4A9w3Ldcpsk5afARKZ9LUVHGVa2ccxS3pxmWqMi8X6sxrE4NxKmEtjX+YZdTymaYAILP2zQeInM482Duw/dfExgIeje0AYA2XMqhkCfEt5aS7qCqQijBY7CBZ03Lo+4z4ufVBk6R/RioC4vwPnA8nbEG2LASMCgL6TIo2/4qm1JsC+kRAIPm9bjZ1c2NXwJuwYIhdt08OXs+/vYdK8e4y6nh1Yi0CsUBeAMgrQ0vIAfaiJluWbMVdpAv4wWPNxHFXiuwYXnuAJyqYMs0SzftW7KVOcXgI7/MBYOTNZLvEpg2ZobwybTpA3iuwXxrraRGm+JJBQCDDpxEeS+igICL1RZqTCZBfILz4LeEEzZuoHHxDl39YSWWUWPCV3wTNQU 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: >> Is this not pretty much equivalent to a volatile read where you're forcing >> the compiler to not optimise this unused thing away? In guard-regions I set: >> >> #define FORCE_READ(x) (*(volatile typeof(x) *)x) >> >> For this purpose, which would make this: >> >> FORCE_READ(addr); >> FORCE_READ(&addr[pagesize]); > > Hmmm, a compiler might be allowed to optimize out a volatile read. Looking into this, the compiler should not be allowed to do that. So FORCE_READ() should work! -- Cheers, David / dhildenb