Linus Torvalds 00a3d660cb Revert "fs: do not prefault sys_write() user buffer pages" ... This reverts commit 998ef75ddb. The commit itself does not appear to be buggy per se, but it is exposing a bug in ext4 (and Ted thinks ext3 too, but we solved that by getting rid of it). It's too late in the release cycle to really worry about this, even if Dave Hansen has a patch that may actually fix the underlying ext4 problem. We can (and should) revisit this for the next release. The problem is that moving the prefaulting later now exposes a special case with partially successful writes that isn't handled correctly. And the prefaulting likely isn't normally even that much of a performance issue - it looks like at least one reason Dave saw this in his performance tests is that he also ran them on Skylake that now supports the new SMAP code, which makes the normally very cheap user space prefaulting noticeably more expensive. Bisected-and-acked-by: Ted Ts'o <tytso@mit.edu> Analyzed-and-acked-by: Dave Hansen <dave.hansen@linux.intel.com> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2015-10-07 08:32:38 +01:00
..
kasan	kasan: fix last shadow judgement in memory_is_poisoned_16()	2015-09-17 21:16:07 -07:00
backing-dev.c	Merge branch 'for-4.3/blkcg' of git://git.kernel.dk/linux-block	2015-09-10 18:56:14 -07:00
balloon_compaction.c	mm/balloon_compaction: fix deflation when compaction is disabled	2014-10-29 16:33:15 -07:00
bootmem.c	bootmem: avoid freeing to bootmem after bootmem is done	2015-09-08 15:35:28 -07:00
cleancache.c	cleancache: remove limit on the number of cleancache enabled filesystems	2015-04-14 16:49:03 -07:00
cma_debug.c	mm/cma_debug: correct size input to bitmap function	2015-07-17 16:39:54 -07:00
cma.c	mm/memblock: add extra "flags" to memblock to allow selection of memory based on attribute	2015-06-24 17:49:44 -07:00
cma.h	mm: cma: mark cma_bitmap_maxno() inline in header	2015-08-14 15:56:32 -07:00
compaction.c	mm/compaction: correct to flush migrated pages if pageblock skip happens	2015-09-08 15:35:28 -07:00
debug-pagealloc.c	mm/debug-pagealloc: make debug-pagealloc boottime configurable	2014-12-13 12:42:48 -08:00
debug.c	mm: introduce idle page tracking	2015-09-10 13:29:01 -07:00
dmapool.c	dmapool: fix overflow condition in pool_find_page()	2015-10-01 21:42:35 -04:00
early_ioremap.c	mm/early_ioremap: add explicit #include of asm/early_ioremap.h	2015-09-11 15:21:34 -07:00
fadvise.c	writeback: implement and use inode_congested()	2015-06-02 08:33:35 -06:00
failslab.c
filemap.c	Revert "fs: do not prefault sys_write() user buffer pages"	2015-10-07 08:32:38 +01:00
frame_vector.c	[media] mm: Provide new get_vaddr_frames() helper	2015-08-16 13:02:47 -03:00
frontswap.c	frontswap: allow multiple backends	2015-06-24 17:49:45 -07:00
gup.c	mm: make GUP handle pfn mapping unless FOLL_GET is requested	2015-09-04 16:54:41 -07:00
highmem.c	mm/highmem: make kmap cache coloring aware	2014-08-06 18:01:22 -07:00
huge_memory.c	mm: introduce idle page tracking	2015-09-10 13:29:01 -07:00
hugetlb_cgroup.c	mm: page_counter: pull "-1" handling out of page_counter_memparse()	2015-02-11 17:06:02 -08:00
hugetlb.c	mm: hugetlbfs: skip shared VMAs when unmapping private pages to satisfy a fault	2015-10-01 21:42:35 -04:00
hwpoison-inject.c	hwpoison: use page_cgroup_ino for filtering by memcg	2015-09-10 13:29:01 -07:00
init-mm.c
internal.h	mm/compaction: correct to flush migrated pages if pageblock skip happens	2015-09-08 15:35:28 -07:00
interval_tree.c	mm: replace vma->sharead.linear with vma->shared	2015-02-10 14:30:31 -08:00
Kconfig	media updates for v4.3-rc1	2015-09-11 16:42:39 -07:00
Kconfig.debug	mm/debug_pagealloc: remove obsolete Kconfig options	2015-01-08 15:10:52 -08:00
kmemcheck.c	mm/slab_common: move kmem_cache definition to internal header	2014-10-09 22:25:50 -04:00
kmemleak-test.c
kmemleak.c	kmemleak: use seq_hex_dump() to dump buffers	2015-09-10 13:29:01 -07:00
ksm.c	mm: remove rest of ACCESS_ONCE() usages	2015-04-15 16:35:18 -07:00
list_lru.c	list_lru: don't call list_lru_from_kmem if the list_head is empty	2015-09-08 15:35:28 -07:00
maccess.c	lib: move strncpy_from_unsafe() into mm/maccess.c	2015-08-31 12:36:10 -07:00
madvise.c	mm: madvise allow remove operation for hugetlbfs	2015-09-08 15:35:28 -07:00
Makefile	media updates for v4.3-rc1	2015-09-11 16:42:39 -07:00
memblock.c	mm/memblock.c: fix comment in __next_mem_range()	2015-09-08 15:35:28 -07:00
memcontrol.c	memcg: remove pcp_counter_lock	2015-10-01 21:42:35 -04:00
memory_hotplug.c	libnvdimm for 4.3:	2015-09-08 14:35:59 -07:00
memory-failure.c	hwpoison: use page_cgroup_ino for filtering by memcg	2015-09-10 13:29:01 -07:00
memory.c	mm: use vma_is_anonymous() in create_huge_pmd() and wp_huge_pmd()	2015-09-10 13:29:01 -07:00
mempolicy.c	mm: rename alloc_pages_exact_node() to __alloc_pages_node()	2015-09-08 15:35:28 -07:00
mempool.c	mm/mempool: allow NULL `pool' pointer in mempool_destroy()	2015-09-08 15:35:28 -07:00
memtest.c	memtest: remove unused header files	2015-09-08 15:35:28 -07:00
migrate.c	memcg: fix dirty page migration	2015-10-01 21:42:35 -04:00
mincore.c	mincore: apply page table walker on do_mincore()	2015-02-11 17:06:06 -08:00
mlock.c	userfaultfd: teach vma_merge to merge across vma->vm_userfaultfd_ctx	2015-09-04 16:54:41 -07:00
mm_init.c	mm: meminit: remove mminit_verify_page_links	2015-06-30 19:44:56 -07:00
mmap.c	mm, dax: VMA with vm_ops->pfn_mkwrite wants to be write-notified	2015-09-22 15:09:53 -07:00
mmu_context.c
mmu_notifier.c	mmu-notifier: add clear_young callback	2015-09-10 13:29:01 -07:00
mmzone.c	mm: microoptimize zonelist operations	2015-02-11 17:06:02 -08:00
mprotect.c	userfaultfd: teach vma_merge to merge across vma->vm_userfaultfd_ctx	2015-09-04 16:54:41 -07:00
mremap.c	mremap: simplify the "overlap" check in mremap_to()	2015-09-04 16:54:41 -07:00
msync.c	mm: remove rest usage of VM_NONLINEAR and pte_file()	2015-02-10 14:30:31 -08:00
nobootmem.c	mm: page_alloc: pass PFN to __free_pages_bootmem	2015-06-30 19:44:55 -07:00
nommu.c	mm, mpx: add "vm_flags_t vm_flags" arg to do_mmap_pgoff()	2015-09-10 13:29:01 -07:00
oom_kill.c	mm, oom: remove unnecessary variable	2015-09-08 15:35:28 -07:00
page_alloc.c	Merge branch 'akpm' (patches from Andrew)	2015-09-08 17:52:23 -07:00
page_counter.c	mm: page_counter: pull "-1" handling out of page_counter_memparse()	2015-02-11 17:06:02 -08:00
page_ext.c	mm: introduce idle page tracking	2015-09-10 13:29:01 -07:00
page_idle.c	mm: introduce idle page tracking	2015-09-10 13:29:01 -07:00
page_io.c	fs: use helper bio_add_page() instead of open coding on bi_io_vec	2015-08-13 12:32:00 -06:00
page_isolation.c	mm, page_isolation: make set/unset_migratetype_isolate() file-local	2015-09-08 15:35:28 -07:00
page_owner.c	mm/page_owner: set correct gfp_mask on page_owner	2015-07-17 16:39:54 -07:00
page-writeback.c	Merge branch 'for-4.3/blkcg' of git://git.kernel.dk/linux-block	2015-09-10 18:56:14 -07:00
pagewalk.c	mm/pagewalk.c: prevent positive return value of walk_page_test() from being passed to callers	2015-03-25 16:20:30 -07:00
percpu-km.c	percpu: implmeent pcpu_nr_empty_pop_pages and chunk->nr_populated	2014-09-02 14:46:05 -04:00
percpu-vm.c	percpu: move region iterations out of pcpu_[de]populate_chunk()	2014-09-02 14:46:02 -04:00
percpu.c	percpu: clean up of schunk->map[] assignment in pcpu_setup_first_chunk	2015-07-21 11:31:00 -04:00
pgtable-generic.c	mm: clarify that the function operates on hugepage pte	2015-06-24 17:49:44 -07:00
process_vm_access.c	process_vm_access: switch to {compat_,}import_iovec()	2015-04-11 22:27:12 -04:00
quicklist.c
readahead.c	writeback: implement and use inode_congested()	2015-06-02 08:33:35 -06:00
rmap.c	mm: introduce idle page tracking	2015-09-10 13:29:01 -07:00
shmem.c	shmem: recalculate file inode when fstat	2015-09-08 15:35:28 -07:00
slab_common.c	memcg: export struct mem_cgroup	2015-09-08 15:35:28 -07:00
slab.c	mm/slab: fix unexpected index mapping result of kmalloc_size(INDEX_NODE+1)	2015-10-01 21:42:35 -04:00
slab.h	mm/slab.h: fix argument order in cache_from_obj's error message	2015-09-04 16:54:41 -07:00
slob.c	mm: rename alloc_pages_exact_node() to __alloc_pages_node()	2015-09-08 15:35:28 -07:00
slub.c	mm: rename alloc_pages_exact_node() to __alloc_pages_node()	2015-09-08 15:35:28 -07:00
sparse-vmemmap.c
sparse.c
swap_cgroup.c	mm: page_cgroup: rename file to mm/swap_cgroup.c	2014-12-10 17:41:09 -08:00
swap_state.c	mm: swap: zswap: maybe_preload & refactoring	2015-09-08 15:35:28 -07:00
swap.c	mm: introduce idle page tracking	2015-09-10 13:29:01 -07:00
swapfile.c	mm: /proc/pid/smaps:: show proportional swap share of the mapping	2015-09-08 15:35:28 -07:00
truncate.c	memcg: add per cgroup dirty page accounting	2015-06-02 08:33:33 -06:00
userfaultfd.c	userfaultfd: avoid mmap_sem read recursion in mcopy_atomic	2015-09-04 16:54:41 -07:00
util.c	mm: uninline and cleanup page-mapping related helpers	2015-04-15 16:35:19 -07:00
vmacache.c	mm,vmacache: count number of system-wide flushes	2014-12-13 12:42:48 -08:00
vmalloc.c	mm/vmalloc: get rid of dirty bitmap inside vmap_block structure	2015-04-15 16:35:18 -07:00
vmpressure.c	mm/vmpressure.c: fix race in vmpressure_work_fn()	2014-12-02 17:32:07 -08:00
vmscan.c	vmscan: fix sane_reclaim helper for legacy memcg	2015-09-22 15:09:53 -07:00
vmstat.c	vmstat: Reduce time interval to stat update on idle cpu	2015-02-11 17:06:07 -08:00
workingset.c	list_lru: add helpers to isolate items	2015-02-12 18:54:10 -08:00
zbud.c	mm: zbud: constify the zbud_ops	2015-09-08 15:35:28 -07:00
zpool.c	zpool: add zpool_has_pool()	2015-09-10 13:29:01 -07:00
zsmalloc.c	mm: zpool: constify the zpool_ops	2015-09-08 15:35:28 -07:00
zswap.c	zswap: change zpool/compressor at runtime	2015-09-10 13:29:01 -07:00