The patch titled Subject: mm: compaction: make sure highest is above the min_pfn has been added to the -mm tree. Its filename is mm-compaction-make-sure-highest-is-above-the-min_pfn.patch This patch should soon appear at https://ozlabs.org/~akpm/mmots/broken-out/mm-compaction-make-sure-highest-is-above-the-min_pfn.patch and later at https://ozlabs.org/~akpm/mmotm/broken-out/mm-compaction-make-sure-highest-is-above-the-min_pfn.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Miaohe Lin <linmiaohe@xxxxxxxxxx> Subject: mm: compaction: make sure highest is above the min_pfn It's not guaranteed that highest will be above the min_pfn. If highest is below the min_pfn, migrate_pfn and free_pfn can meet prematurely and lead to some useless work. Make sure highest is above min_pfn to avoid making a futile effort. Link: https://lkml.kernel.org/r/20220418141253.24298-13-linmiaohe@xxxxxxxxxx Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx> Cc: Charan Teja Kalla <charante@xxxxxxxxxxxxxx> Cc: David Hildenbrand <david@xxxxxxxxxx> Cc: Pintu Kumar <pintu@xxxxxxxxxxxxxx> Cc: Vlastimil Babka <vbabka@xxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/compaction.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/mm/compaction.c~mm-compaction-make-sure-highest-is-above-the-min_pfn +++ a/mm/compaction.c @@ -1532,7 +1532,7 @@ fast_isolate_freepages(struct compact_co * not found, be pessimistic for direct compaction * and use the min mark. */ - if (highest) { + if (highest >= min_pfn) { page = pfn_to_page(highest); cc->free_pfn = highest; } else { _ Patches currently in -mm which might be from linmiaohe@xxxxxxxxxx are mm-shmem-make-shmem_init-return-void.patch mm-memcg-remove-unneeded-nr_scanned.patch mm-mmapc-use-helper-mlock_future_check.patch mm-mremap-use-helper-mlock_future_check.patch mm-mremap-avoid-unneeded-do_munmap-call.patch mm-memory-failurec-minor-cleanup-for-hwpoisonhandlable.patch mm-memory-failurec-dissolve-truncated-hugetlb-page.patch mm-vmscan-remove-obsolete-comment-in-get_scan_count.patch mm-vmscan-fix-comment-for-current_may_throttle.patch mm-z3fold-declare-z3fold_mount-with-__init.patch mm-z3fold-remove-obsolete-comment-in-z3fold_alloc.patch mm-z3fold-minor-clean-up-for-z3fold_free.patch mm-z3fold-remove-unneeded-page_mapcount_reset-and-clearpageprivate.patch mm-z3fold-remove-confusing-local-variable-l-reassignment.patch mm-z3fold-move-decrement-of-pool-pages_nr-into-__release_z3fold_page.patch mm-z3fold-remove-redundant-list_del_init-of-zhdr-buddy-in-z3fold_free.patch mm-z3fold-remove-unneeded-page_headless-check-in-free_handle.patch mm-compaction-use-helper-isolation_suitable.patch drivers-base-nodec-fix-compaction-sysfs-file-leak.patch mm-migration-remove-unneeded-local-variable-mapping_locked.patch mm-migration-remove-unneeded-local-variable-page_lru.patch mm-migration-use-helper-function-vma_lookup-in-add_page_for_migration.patch mm-migration-use-helper-macro-min-in-do_pages_stat.patch mm-migration-avoid-unneeded-nodemask_t-initialization.patch mm-migration-remove-some-duplicated-codes-in-migrate_pages.patch mm-migration-fix-potential-page-refcounts-leak-in-migrate_pages.patch mm-migration-fix-potential-invalid-node-access-for-reclaim-based-migration.patch mm-migration-fix-possible-do_pages_stat_array-racing-with-memory-offline.patch mm-compaction-remove-unneeded-return-value-of-kcompactd_run.patch mm-compaction-remove-unneeded-pfn-update.patch mm-compaction-remove-unneeded-assignment-to-isolate_start_pfn.patch mm-compaction-clean-up-comment-for-sched-contention.patch mm-compaction-clean-up-comment-about-suitable-migration-target-recheck.patch mm-compaction-use-compact_cluster_max-in-compactionc.patch mm-compaction-use-helper-compound_nr-in-isolate_migratepages_block.patch mm-compaction-clean-up-comment-about-async-compaction-in-isolate_migratepages.patch mm-compaction-avoid-possible-null-pointer-dereference-in-kcompactd_cpu_online.patch mm-compaction-make-compaction_zonelist_suitable-return-false-when-compact_success.patch mm-compaction-simplify-the-code-in-__compact_finished.patch mm-compaction-make-sure-highest-is-above-the-min_pfn.patch