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charset="UTF-8" X-Rspam-User: X-Stat-Signature: kyyxq3b4n9coomk7ztgd55jw9qdwhq4m X-Rspamd-Server: rspam07 X-Rspamd-Queue-Id: 504274001A X-HE-Tag: 1687174617-194925 X-HE-Meta: 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 Q3HoGibN Nxxs1bfSLDtqd4ACRmZGqO/CRNt4OF5OGIpcHsKqvHgsehRt5MQEBgntDnPl4ognmPl574s/dFzobSHBrTtdlMdSnN75rr1m5t7LHcCDzAE7g/A5CnKPzY45zp0wE+Q66WxowjYInCtxMD7PCiSDR2sN4qA5kxqEha8E0ZS1RuooXUoIOXlzBoIKFo2jLBLYOLPGpRJWSgW3EabYtSQOofm4x08pda3HC3MrCO+/hxpTS5/EQxYyuzaN3IsPFqqq2l7eETFrmEcuQWspJiVSeNbOQGhsaLqTes8bT6LLWvaz8nz/+VVRoiIa519cK7URtF696Y3TE4yNoleL8aW4lXsUKyUV27Ojf1mnWobpGn2F1c9d8PlCYU0T5Bp9ICq/xpxYf87IM1gDIKcVury0ux9kC3VFfSk5XcY8miZcg9quy+5g= 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, 19 Jun 2023 at 12:15, Dmitry Vyukov wrote: > On Mon, 19 Jun 2023 at 12:12, Chanho Min wrote: > > > > This patch removes description of the KASAN_HW_TAGS's memory consumption. > > KASAN_HW_TAGS does not set 1/32nd shadow memory. > > The hardware still allocates/uses shadow in MTE. > Though, it may be 1/16-th, not sure. I think the point is that it depends on the hardware implementation of MTE. There are a range of possibilities, but enabling KASAN_HW_TAGS doesn't consume any extra memory for tags itself if the hardware has to enable MTE and provision tag space via firmware to begin with. > > Signed-off-by: Chanho Min I think you just have to be a bit clearer in the commit description, just briefly mentioning how/where the tag space is allocated in hardware that do support MTE. Then removing this line is probably fair, if KASAN_HW_TAGS isn't the direct reason for tag memory being allocated.