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https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
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1cb5d11a37
"man 2 migrate_pages" says "On success migrate_pages() returns the number of pages that could not be moved". Although 5.3 and 5.4 commits fixed mbind(MPOL_MF_STRICT|MPOL_MF_MOVE*) to fail with EIO when not all pages could be moved (because some could not be isolated for migration), migrate_pages(2) was left still reporting only those pages failing at the migration stage, forgetting those failing at the earlier isolation stage. Fix that by accumulating a long nr_failed count in struct queue_pages, returned by queue_pages_range() when it's not returning an error, for adding on to the nr_failed count from migrate_pages() in mm/migrate.c. A count of pages? It's more a count of folios, but changing it to pages would entail more work (also in mm/migrate.c): does not seem justified. queue_pages_range() itself should only return -EIO in the "strictly unmovable" case (STRICT without any MOVEs): in that case it's best to break out as soon as nr_failed gets set; but otherwise it should continue to isolate pages for MOVing even when nr_failed - as the mbind(2) manpage promises. There's a case when nr_failed should be incremented when it was missed: queue_folios_pte_range() and queue_folios_hugetlb() count the transient migration entries, like queue_folios_pmd() already did. And there's a case when nr_failed should not be incremented when it would have been: in meeting later PTEs of the same large folio, which can only be isolated once: fixed by recording the current large folio in struct queue_pages. Clean up the affected functions, fixing or updating many comments. Bool migrate_folio_add(), without -EIO: true if adding, or if skipping shared (but its arguable folio_estimated_sharers() heuristic left unchanged). Use MPOL_MF_WRLOCK flag to queue_pages_range(), instead of bool lock_vma. Use explicit STRICT|MOVE* flags where queue_pages_test_walk() checks for skipping, instead of hiding them behind MPOL_MF_VALID. Link: https://lkml.kernel.org/r/9a6b0b9-3bb-dbef-8adf-efab4397b8d@google.com Signed-off-by: Hugh Dickins <hughd@google.com> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: "Huang, Ying" <ying.huang@intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Lameter <cl@linux.com> Cc: David Hildenbrand <david@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Tejun heo <tj@kernel.org> Cc: Vishal Moola (Oracle) <vishal.moola@gmail.com> Cc: Yang Shi <shy828301@gmail.com> Cc: Yosry Ahmed <yosryahmed@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
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.. | ||
damon | ||
kasan | ||
kfence | ||
kmsan | ||
backing-dev.c | ||
balloon_compaction.c | ||
bootmem_info.c | ||
cma.c | ||
cma.h | ||
cma_debug.c | ||
cma_sysfs.c | ||
compaction.c | ||
debug.c | ||
debug_page_alloc.c | ||
debug_page_ref.c | ||
debug_vm_pgtable.c | ||
dmapool.c | ||
dmapool_test.c | ||
early_ioremap.c | ||
fadvise.c | ||
fail_page_alloc.c | ||
failslab.c | ||
filemap.c | ||
folio-compat.c | ||
gup.c | ||
gup_test.c | ||
gup_test.h | ||
highmem.c | ||
hmm.c | ||
huge_memory.c | ||
hugetlb.c | ||
hugetlb_cgroup.c | ||
hugetlb_vmemmap.c | ||
hugetlb_vmemmap.h | ||
hwpoison-inject.c | ||
init-mm.c | ||
internal.h | ||
interval_tree.c | ||
io-mapping.c | ||
ioremap.c | ||
Kconfig | ||
Kconfig.debug | ||
khugepaged.c | ||
kmemleak.c | ||
ksm.c | ||
list_lru.c | ||
maccess.c | ||
madvise.c | ||
Makefile | ||
mapping_dirty_helpers.c | ||
memblock.c | ||
memcontrol.c | ||
memfd.c | ||
memory-failure.c | ||
memory-tiers.c | ||
memory.c | ||
memory_hotplug.c | ||
mempolicy.c | ||
mempool.c | ||
memremap.c | ||
memtest.c | ||
migrate.c | ||
migrate_device.c | ||
mincore.c | ||
mlock.c | ||
mm_init.c | ||
mm_slot.h | ||
mmap.c | ||
mmap_lock.c | ||
mmu_gather.c | ||
mmu_notifier.c | ||
mmzone.c | ||
mprotect.c | ||
mremap.c | ||
msync.c | ||
nommu.c | ||
oom_kill.c | ||
page-writeback.c | ||
page_alloc.c | ||
page_counter.c | ||
page_ext.c | ||
page_idle.c | ||
page_io.c | ||
page_isolation.c | ||
page_owner.c | ||
page_poison.c | ||
page_reporting.c | ||
page_reporting.h | ||
page_table_check.c | ||
page_vma_mapped.c | ||
pagewalk.c | ||
percpu-internal.h | ||
percpu-km.c | ||
percpu-stats.c | ||
percpu-vm.c | ||
percpu.c | ||
pgalloc-track.h | ||
pgtable-generic.c | ||
process_vm_access.c | ||
ptdump.c | ||
readahead.c | ||
rmap.c | ||
rodata_test.c | ||
secretmem.c | ||
shmem.c | ||
shmem_quota.c | ||
show_mem.c | ||
shrinker.c | ||
shrinker_debug.c | ||
shuffle.c | ||
shuffle.h | ||
slab.c | ||
slab.h | ||
slab_common.c | ||
slub.c | ||
sparse-vmemmap.c | ||
sparse.c | ||
swap.c | ||
swap.h | ||
swap_cgroup.c | ||
swap_slots.c | ||
swap_state.c | ||
swapfile.c | ||
truncate.c | ||
usercopy.c | ||
userfaultfd.c | ||
util.c | ||
vmalloc.c | ||
vmpressure.c | ||
vmscan.c | ||
vmstat.c | ||
workingset.c | ||
z3fold.c | ||
zbud.c | ||
zpool.c | ||
zsmalloc.c | ||
zswap.c |