linux/mm
Ralph Campbell 07707125ae mm/migrate: properly preserve write attribute in special migrate entry
Use of pte_write(pte) is only valid for present pte, the common code
which set the migration entry can be reach for both valid present pte
and special swap entry (for device memory).  Fix the code to use the
mpfn value which properly handle both cases.

On x86 this did not have any bad side effect because pte write bit is
below PAGE_BIT_GLOBAL and thus special swap entry have it set to 0 which
in turn means we were always creating read only special migration entry.

So once migration did finish we always write protected the CPU page
table entry (moreover this is only an issue when migrating from device
memory to system memory).  End effect is that CPU write access would
fault again and restore write permission.

This behaviour isn't too bad; it just burns CPU cycles by forcing CPU to
take a second fault on write access. ie, double faulting the same
address.  There is no corruption or incorrect states (it behaves as a
COWed page from a fork with a mapcount of 1).

Link: http://lkml.kernel.org/r/20180402023506.12180-1-jglisse@redhat.com
Signed-off-by: Ralph Campbell <rcampbell@nvidia.com>
Signed-off-by: Jérôme Glisse <jglisse@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 10:28:31 -07:00
..
kasan slab, slub: skip unnecessary kasan_cache_shutdown() 2018-04-05 21:36:24 -07:00
backing-dev.c mm/vmscan: don't mess with pgdat->flags in memcg reclaim 2018-04-11 10:28:30 -07:00
balloon_compaction.c virtio_balloon: fix deadlock on OOM 2017-11-14 23:57:38 +02:00
bootmem.c mm: docs: fix parameter names mismatch 2018-02-06 18:32:48 -08:00
cleancache.c fs: switch ->s_uuid to uuid_t 2017-06-05 16:59:12 +02:00
cma_debug.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
cma.c headers: untangle kmemleak.h from mm.h 2018-04-05 21:36:27 -07:00
cma.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
compaction.c mm: kernel-doc: add missing parameter descriptions 2018-04-05 21:36:27 -07:00
debug_page_ref.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
debug.c mm/debug.c: provide useful debugging information for VM_BUG 2018-01-04 16:45:09 -08:00
dmapool.c
early_ioremap.c mm/early_ioremap: Fix boot hang with earlyprintk=efi,keep 2017-12-11 14:54:44 +01:00
fadvise.c mm: add ksys_fadvise64_64() helper; remove in-kernel call to sys_fadvise64_64() 2018-04-02 20:16:10 +02:00
failslab.c mm: make should_failslab always available for fault injection 2018-04-05 21:36:26 -07:00
filemap.c mm/filemap.c: remove include of hardirq.h 2018-01-31 17:18:36 -08:00
frame_vector.c mm/frame_vector.c: release a semaphore in 'get_vaddr_frames()' 2017-12-14 16:00:48 -08:00
frontswap.c
gup_benchmark.c mm: add infrastructure for get_user_pages_fast() benchmarking 2017-11-17 16:10:04 -08:00
gup.c mm/gup.c: fix coding style issues. 2018-04-05 21:36:26 -07:00
highmem.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
hmm.c mm/hmm.c: remove superfluous RCU protection around radix tree lookup 2018-04-11 10:28:31 -07:00
huge_memory.c mm/huge_memory.c: reorder operations in __split_huge_page_tail() 2018-04-05 21:36:25 -07:00
hugetlb_cgroup.c
hugetlb.c mm, hugetlbfs: introduce ->pagesize() to vm_operations_struct 2018-04-05 21:36:26 -07:00
hwpoison-inject.c mm/memory_failure: Remove unused trapno from memory_failure 2018-01-23 12:17:42 -06:00
init-mm.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
internal.h Revert "mm, thp: Do not make pmd/pud dirty without a reason" 2017-11-29 09:01:01 -08:00
interval_tree.c mm/interval_tree.c: use vma_pages() helper 2018-01-31 17:18:37 -08:00
Kconfig treewide: simplify Kconfig dependencies for removed archs 2018-03-26 15:55:57 +02:00
Kconfig.debug kmemcheck: rip it out 2017-11-15 18:21:05 -08:00
khugepaged.c mm, thp: do not cause memcg oom for thp 2018-03-22 17:07:02 -07:00
kmemleak-test.c
kmemleak.c mm: kernel-doc: add missing parameter descriptions 2018-04-05 21:36:27 -07:00
ksm.c mm/ksm: fix interaction with THP 2018-04-05 21:36:27 -07:00
list_lru.c mm: make counting of list_lru_one::nr_items lockless 2018-04-05 21:36:27 -07:00
maccess.c mm: docs: fix parameter names mismatch 2018-02-06 18:32:48 -08:00
madvise.c mm/memory_failure: Remove unused trapno from memory_failure 2018-01-23 12:17:42 -06:00
Makefile mm/swap_slots.c: use conditional compilation 2018-04-05 21:36:24 -07:00
memblock.c powerpc updates for 4.17 2018-04-07 12:08:19 -07:00
memcontrol.c mm/memcontrol.c: fix parameter description mismatch 2018-03-28 13:42:05 -10:00
memory_hotplug.c mm: kernel-doc: add missing parameter descriptions 2018-04-05 21:36:27 -07:00
memory-failure.c mm: hwpoison: disable memory error handling on 1GB hugepage 2018-04-05 21:36:25 -07:00
memory.c mm: swap: unify cluster-based and vma-based swap readahead 2018-04-05 21:36:25 -07:00
mempolicy.c Merge branch 'syscalls-next' of git://git.kernel.org/pub/scm/linux/kernel/git/brodo/linux 2018-04-02 21:22:12 -07:00
mempool.c kasan: detect invalid frees for large mempool objects 2018-02-06 18:32:43 -08:00
memtest.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
migrate.c mm/migrate: properly preserve write attribute in special migrate entry 2018-04-11 10:28:31 -07:00
mincore.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
mlock.c mm, mlock, vmscan: no more skipping pagevecs 2018-02-21 15:35:42 -08:00
mm_init.c
mmap.c mm: always print RLIMIT_DATA warning 2018-04-05 21:36:24 -07:00
mmu_context.c
mmu_notifier.c mm, mmu_notifier: annotate mmu notifiers with blockable invalidate callbacks 2018-01-31 17:18:38 -08:00
mmzone.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
mprotect.c sched/numa: avoid trapping faults and attempting migration of file-backed dirty pages 2018-04-11 10:28:31 -07:00
mremap.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
msync.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
nobootmem.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
nommu.c mm/nommu: remove description of alloc_vm_area 2018-04-05 21:36:26 -07:00
oom_kill.c mm,oom_reaper: check for MMF_OOM_SKIP before complaining 2018-04-05 21:36:27 -07:00
page_alloc.c mm: treat indirectly reclaimable memory as available in MemAvailable 2018-04-11 10:28:29 -07:00
page_counter.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
page_ext.c mm/page_ext.c: make page_ext_init a noop when CONFIG_PAGE_EXTENSION but nothing uses it 2018-01-31 17:18:39 -08:00
page_idle.c mm: thp: fix potential clearing to referenced flag in page_idle_clear_pte_refs_one() 2018-04-05 21:36:25 -07:00
page_io.c block: convert to bio_first_bvec_all & bio_first_page_all 2018-01-06 09:18:00 -07:00
page_isolation.c mm/page_isolation.c: make start_isolate_page_range() fail if already isolated 2018-04-05 21:36:27 -07:00
page_owner.c mm/page_owner.c: make early_page_owner_param() __init 2018-04-05 21:36:26 -07:00
page_poison.c mm/page_poison.c: make early_page_poison_param() __init 2018-04-05 21:36:26 -07:00
page_vma_mapped.c mm, page_vma_mapped: Introduce pfn_in_hpage() 2018-01-22 12:15:57 -08:00
page-writeback.c Revert "mm/page-writeback.c: print a warning if the vm dirtiness settings are illogical" 2017-11-29 18:40:43 -08:00
pagewalk.c mm: kernel-doc: add missing parameter descriptions 2018-04-05 21:36:27 -07:00
percpu-internal.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
percpu-km.c percpu: allow select gfp to be passed to underlying allocators 2018-02-18 05:33:01 -08:00
percpu-stats.c mm: reuse DEFINE_SHOW_ATTRIBUTE() macro 2018-04-05 21:36:25 -07:00
percpu-vm.c percpu: allow select gfp to be passed to underlying allocators 2018-02-18 05:33:01 -08:00
percpu.c arch: remove obsolete architecture ports 2018-04-02 20:20:12 -07:00
pgtable-generic.c mm: do not lose dirty and accessed bits in pmdp_invalidate() 2018-01-31 17:18:38 -08:00
process_vm_access.c mm: docs: add blank lines to silence sphinx "Unexpected indentation" errors 2018-02-06 18:32:48 -08:00
quicklist.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
readahead.c mm: add ksys_readahead() helper; remove in-kernel calls to sys_readahead() 2018-04-02 20:16:12 +02:00
rmap.c mm: kernel-doc: add missing parameter descriptions 2018-04-05 21:36:27 -07:00
rodata_test.c mm: fix RODATA_TEST failure "rodata_test: test data was not read only" 2017-10-03 17:54:24 -07:00
shmem.c mm: swap: unify cluster-based and vma-based swap readahead 2018-04-05 21:36:25 -07:00
slab_common.c mm: make should_failslab always available for fault injection 2018-04-05 21:36:26 -07:00
slab.c slab, slub: skip unnecessary kasan_cache_shutdown() 2018-04-05 21:36:24 -07:00
slab.h slab, slub: skip unnecessary kasan_cache_shutdown() 2018-04-05 21:36:24 -07:00
slob.c slab, slub, slob: add slab_flags_t 2017-11-15 18:21:01 -08:00
slub.c slab, slub: skip unnecessary kasan_cache_shutdown() 2018-04-05 21:36:24 -07:00
sparse-vmemmap.c mm: merge vmem_altmap_alloc into altmap_alloc_block_buf 2018-01-08 11:46:23 -08:00
sparse.c mm/memory_hotplug: optimize memory hotplug 2018-04-05 21:36:25 -07:00
swap_cgroup.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
swap_slots.c mm/swap_slots.c: use conditional compilation 2018-04-05 21:36:24 -07:00
swap_state.c mm/swap_state.c: make bool enable_vma_readahead and swap_vma_readahead() static 2018-04-05 21:36:27 -07:00
swap.c mm/swap.c: remove @cold parameter description for release_pages() 2018-04-05 21:36:26 -07:00
swapfile.c vfs: do bulk POLL* -> EPOLL* replacement 2018-02-11 14:34:03 -08:00
truncate.c mm: add unmap_mapping_pages() 2018-01-31 17:18:37 -08:00
usercopy.c usercopy: WARN() on slab cache usercopy region violations 2018-01-15 12:07:48 -08:00
userfaultfd.c mm/userfaultfd.c: remove duplicate include 2018-02-06 18:32:47 -08:00
util.c mm: treat indirectly reclaimable memory as free in overcommit logic 2018-04-11 10:28:29 -07:00
vmacache.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
vmalloc.c vmalloc: fix __GFP_HIGHMEM usage for vmalloc_32 on 32b systems 2018-02-21 15:35:43 -08:00
vmpressure.c mm, vmpressure: pass-through notification support 2017-07-10 16:32:31 -07:00
vmscan.c mm, vmscan, tracing: use pointer to reclaim_stat struct in trace event 2018-04-11 10:28:30 -07:00
vmstat.c mm: introduce NR_INDIRECTLY_RECLAIMABLE_BYTES 2018-04-11 10:28:29 -07:00
workingset.c mm, truncate: do not check mapping for every page being truncated 2017-11-15 18:21:06 -08:00
z3fold.c z3fold: limit use of stale list for allocation 2018-04-05 21:36:25 -07:00
zbud.c mm: docs: fix parameter names mismatch 2018-02-06 18:32:48 -08:00
zpool.c mm/zpool.c: zpool_evictable: fix mismatch in parameter name and kernel-doc 2018-02-21 15:35:43 -08:00
zsmalloc.c mm: kernel-doc: add missing parameter descriptions 2018-04-05 21:36:27 -07:00
zswap.c mm, swap, frontswap: fix THP swap if frontswap enabled 2018-02-21 15:35:43 -08:00