linux/mm
Miklos Szeredi 84209e02de mm: dont clear PG_uptodate on truncate/invalidate
Brian Wang reported that a FUSE filesystem exported through NFS could
return I/O errors on read.  This was traced to splice_direct_to_actor()
returning a short or zero count when racing with page invalidation.

However this is not FUSE or NFSD specific, other filesystems (notably
NFS) also call invalidate_inode_pages2() to purge stale data from the
cache.

If this happens while such pages are sitting in a pipe buffer, then
splice(2) from the pipe can return zero, and read(2) from the pipe can
return ENODATA.

The zero return is especially bad, since it implies end-of-file or
disconnected pipe/socket, and is documented as such for splice.  But
returning an error for read() is also nasty, when in fact there was no
error (data becoming stale is not an error).

The same problems can be triggered by "hole punching" with
madvise(MADV_REMOVE).

Fix this by not clearing the PG_uptodate flag on truncation and
invalidation.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Acked-by: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-08-02 09:12:34 -07:00
..
Kconfig mmu-notifiers: core 2008-07-28 16:30:21 -07:00
Makefile mmu-notifiers: core 2008-07-28 16:30:21 -07:00
allocpercpu.c mm/allocpercpu.c: make 4 functions static 2008-07-26 12:00:12 -07:00
backing-dev.c mm: bdi: fix race in bdi_class device creation 2008-05-20 13:31:53 -07:00
bootmem.c bootmem: replace node_boot_start in struct bootmem_data 2008-07-24 10:47:20 -07:00
bounce.c block: Initial support for data-less (or empty) barrier support 2007-10-16 11:03:56 +02:00
dmapool.c dmapool: enable debugging for CONFIG_SLUB_DEBUG_ON too 2008-04-28 08:58:20 -07:00
fadvise.c xip: support non-struct page backed memory 2008-04-28 08:58:23 -07:00
filemap.c Fix off-by-one error in iov_iter_advance() 2008-07-30 14:50:18 -07:00
filemap_xip.c mmu-notifiers: core 2008-07-28 16:30:21 -07:00
fremap.c mmu-notifiers: core 2008-07-28 16:30:21 -07:00
highmem.c highmem: Export totalhigh_pages. 2008-07-19 22:39:46 -07:00
hugetlb.c mm/hugetlb: don't crash when HPAGE_SHIFT is 0 2008-08-01 12:46:41 -07:00
internal.h mm: export prep_compound_page to mm 2008-07-24 10:47:17 -07:00
maccess.c kgdb: fix optional arch functions and probe_kernel_* 2008-04-17 20:05:39 +02:00
madvise.c madvise: update function comment of madvise_dontneed 2008-07-30 09:41:45 -07:00
memcontrol.c memcg: remove redundant check in move_task() 2008-07-30 09:41:44 -07:00
memory.c Remove EXPORTS of follow_page & zap_page_range 2008-08-01 13:19:16 -07:00
memory_hotplug.c memory-hotplug: add sysfs removable attribute for hotplug memory remove 2008-07-24 10:47:21 -07:00
mempolicy.c hugetlb: modular state for hugetlb page size 2008-07-24 10:47:17 -07:00
mempool.c spelling fixes: mm/ 2007-10-20 01:27:18 +02:00
migrate.c mm: spinlock tree_lock 2008-07-26 12:00:06 -07:00
mincore.c mm: remove nopage 2008-04-28 08:58:18 -07:00
mlock.c do not limit locked memory when RLIMIT_MEMLOCK is RLIM_INFINITY 2007-07-16 09:05:37 -07:00
mm_init.c mm: create /sys/kernel/mm 2008-07-24 10:47:17 -07:00
mmap.c mmu-notifiers: core 2008-07-28 16:30:21 -07:00
mmu_notifier.c mmu-notifiers: core 2008-07-28 16:30:21 -07:00
mmzone.c mm: filter based on a nodemask as well as a gfp_mask 2008-04-28 08:58:19 -07:00
mprotect.c mmu-notifiers: core 2008-07-28 16:30:21 -07:00
mremap.c mmu-notifiers: core 2008-07-28 16:30:21 -07:00
msync.c Detach sched.h from mm.h 2007-05-21 09:18:19 -07:00
nommu.c tracehook: tracehook_expect_breakpoints 2008-07-26 12:00:09 -07:00
oom_kill.c oom_kill: remove unused parameter in badness() 2008-04-28 08:58:26 -07:00
page-writeback.c mm: spinlock tree_lock 2008-07-26 12:00:06 -07:00
page_alloc.c mm: remove find_max_pfn_with_active_regions 2008-07-30 09:41:44 -07:00
page_io.c mm: fix PageUptodate data race 2008-02-05 09:44:19 -08:00
page_isolation.c memory hotremove: unset migrate type "ISOLATE" after removal 2007-11-14 18:45:38 -08:00
pagewalk.c pagemap: pass mm into pagewalkers 2008-06-12 18:05:41 -07:00
pdflush.c pdflush: use time_after() instead of open-coding it 2008-07-25 10:53:28 -07:00
prio_tree.c spelling fixes: mm/ 2007-10-20 01:27:18 +02:00
quicklist.c quicklists: Only consider memory that can be used with GFP_KERNEL 2008-01-14 08:52:22 -08:00
readahead.c mm: readahead scan lockless 2008-07-26 12:00:06 -07:00
rmap.c [S390] Optimize storage key operations for anon pages 2008-08-01 16:39:30 +02:00
shmem.c tmpfs: fix kernel BUG in shmem_delete_inode 2008-07-28 16:30:20 -07:00
shmem_acl.c [PATCH] sanitize ->permission() prototype 2008-07-26 20:53:14 -04:00
slab.c SL*B: drop kmem cache argument from constructor 2008-07-26 12:00:07 -07:00
slob.c SL*B: drop kmem cache argument from constructor 2008-07-26 12:00:07 -07:00
slub.c SL*B: drop kmem cache argument from constructor 2008-07-26 12:00:07 -07:00
sparse-vmemmap.c Christoph has moved 2008-07-04 10:40:04 -07:00
sparse.c make mm/sparse.c: make a function static 2008-07-26 12:00:12 -07:00
swap.c swap: update function comment of release_pages 2008-07-30 09:41:46 -07:00
swap_state.c mm: print swapcache page count in show_swap_cache_info() 2008-07-26 12:00:10 -07:00
swapfile.c swapfile/vmscan: update comments related to vmscan functions 2008-07-30 09:41:46 -07:00
thrash.c Bug in mm/thrash.c function grab_swap_token() 2007-05-11 08:29:32 -07:00
tiny-shmem.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6 2008-03-25 08:57:47 -07:00
truncate.c mm: dont clear PG_uptodate on truncate/invalidate 2008-08-02 09:12:34 -07:00
util.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6 2008-07-26 20:17:56 -07:00
vmalloc.c Use WARN() in mm/vmalloc.c 2008-07-26 12:00:07 -07:00
vmscan.c do_try_to_free_page: update comments related to vmscan functions 2008-07-30 09:41:46 -07:00
vmstat.c mm/vmstat.c: proper externs 2008-07-24 10:47:14 -07:00