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charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.54.3 (3.54.3-1.fc41) MIME-Version: 1.0 X-Rspamd-Queue-Id: A4D57100011 X-Stat-Signature: b9hw3ko4cbmi954f3jg8jtf8uz4ai5es X-Rspam-User: X-Rspamd-Server: rspam09 X-HE-Tag: 1758122499-983718 X-HE-Meta: U2FsdGVkX18qLH5cas6HxrQY6gCtqqLTp8WvPjaJ1usi/52AB8LZ7wN4maHdCRPzfM8ZOapAx1dJb95ONrJi+M41i2KVLF43VTaOLNsXROb1WQcmQXM6gwI/TdKrBYgpQa1oAdZnA8OY9/vEzzYrRM7gIt10wfilY+Ajg0i9qENeqfDpMbmLX+mhuNJwCr/V7xxFvkzCzSnkx9NQTByfZAyPkMkAT4Ba762GgdRlbXd1LjB39BS8LJTT7vpCYPz4SNylTbJx2GXWbhVRfYxBCHMfNYW/SLGBKOS04qPY9/XiurecMulCIYMJP0LELs2p30tz4/mKm8Dz1lrTKFHBfdtiWBDaM2vD7kKq14ftrGyPgaBivIpqeKmfaHkExp/Pt0t7EHB5T4C1vS8MsBzHLD4OxvM7rS7zbknLBwdEBVPWw6x+ZLUrFBT2CCPWgUHJGjjksY0CCAcgIeJKk5/QC/NkREd5pmURxACmDZ9wVQJy2UYUtrNHB7jKoZ2utYNvQA9EampitGPLaXHiUKRecGMXw7PybN3l4a4vHJPz8wiYh8O19Y3BJ7zzfp9rYz0mfYZyeKnnsfauIWBshnvHZSdzwiwzS/OEmDddkxIaT9NG6a1rfs52ZWkxrlAQa0/U5e5Z0qJppWQXOSt0RXEVve5lRJhnfsYxYCtfDLsHxDJ5gslPzuKs7C9MYQJUPLOSIK6K4nxcpgHzxB5/ft2N+SMPXYxdIvcHciypfC6RaPEnrrFpw+el56EyUUDlUSqasIhR13F/qgwMiO47ZmmD/maxNAeZ3NNS8RB9VBFt7lFLULQXPR5hOHwmVQ5vPXn5yGHsiFrH4rsyyRxEdai9qZnT+T+I/5pOJrtehabRehmR/a6cqMEvSmlmXSYU/yZOn6ZZUk7KPGbvYaSGdebONK+YL/LDNYa+slHnFL8UQTPZ11KVPx1lPlQuCfrDiAwZ8CmxZAv/MGVUE3uB49r RPDO0AIc 1f05JpqD5tFW9nzJHqy37QAjsfhGh7VIsfPmhtpm9JqRCph0KnikB86LO+SoRU2fdlYFEVeAsVoPqR+Oa7TO+jpkiiOPtI6t+/vOu5vhPd1X6JMTGYRbCxwfonmhB2Y/jgRcBuZ29uKBXNpBfq8pShDL3988kf8KUvcIyBvRwTKbT3lu6/gj4NyPECFfGNEIpI1wE6kWWlwBEjLsh4dFuOkTpEJc5qaYDWPK4 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 Mon, 2025-09-15 at 19:51 +0000, Frank van der Linden wrote: > CMA areas are normally not very large, but HugeTLB CMA is an > exception. hugetlb_cma, used for 'gigantic' pages (usually > 1G), can take up many gigabytes of memory. >=20 > As such, it is potentially the largest source of 'false OOM' > conditions, The false OOM kills also seem to happen when a system does not use hugetlbfs at all, but a cgroup simply has most/all of its reclaimable memory in a CMA region, and then tries to do a kernel allocation. Would it make sense to call hugetlb_cma_balance() from the pageout code instead, when the pageout code is trying to free non-CMA memory, but ended up freeing mostly/only CMA memory? --=20 All Rights Reversed.