kernel_samsung_sm7125

jenna

History

Zach Brown 65b8291c40 [PATCH] dio: invalidate clean pages before dio write This patch fixes a user-triggerable oops that was reported by Leonid Ananiev as archived at http://lkml.org/lkml/2007/2/8/337. dio writes invalidate clean pages that intersect the written region so that subsequent buffered reads go to disk to read the new data. If this fails the interface tries to tell the caller that the cache is inconsistent by returning EIO. Before this patch we had the problem where this invalidation failure would clobber -EIOCBQUEUED as it made its way from fs/direct-io.c to fs/aio.c. Both fs/aio.c and bio completion call aio_complete() and we reference freed memory, usually oopsing. This patch addresses this problem by invalidating before the write so that we can cleanly return -EIO before ->direct_IO() has had a chance to return -EIOCBQUEUED. There is a compromise here. During the dio write we can fault in mmap()ed pages which intersect the written range with get_user_pages() if the user provided them for the source buffer. This is a crazy thing to do, but we can make it mostly work in most cases by trying the invalidation again. The compromise is that we won't return an error if this second invalidation fails if it's an AIO write and we have -EIOCBQUEUED. This was tested by having two processes race performing large O_DIRECT and buffered ordered writes. Within minutes ext3 would see a race between ext3_releasepage() and jbd holding a reference on ordered data buffers and would cause invalidation to fail, panicing the box. The test can be found in the 'aio_dio_bugs' test group in test.kernel.org/autotest. After this patch the test passes. Signed-off-by: Zach Brown <zach.brown@oracle.com> Signed-off-by: Benjamin LaHaise <bcrl@kvack.org> Cc: Leonid Ananiev <leonid.i.ananiev@linux.intel.com> Cc: Nick Piggin <nickpiggin@yahoo.com.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		18 years ago
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Kconfig	[PATCH] Set CONFIG_ZONE_DMA for arches with GENERIC_ISA_DMA	18 years ago
Makefile	…
allocpercpu.c	…
backing-dev.c	…
bootmem.c	…
bounce.c	…
fadvise.c	…
filemap.c	[PATCH] dio: invalidate clean pages before dio write	18 years ago
filemap.h	…
filemap_xip.c	…
fremap.c	…
highmem.c	[PATCH] Use ZVC for free_pages	18 years ago
hugetlb.c	[PATCH] hugetlb: preserve hugetlb pte dirty state	18 years ago
internal.h	…
madvise.c	[PATCH] mm: fix madvise infinine loop	18 years ago
memory.c	[PATCH] Add NOPFN_REFAULT result from vm_ops->nopfn()	18 years ago
memory_hotplug.c	…
mempolicy.c	[PATCH] Page migration: Fix vma flag checking	18 years ago
mempool.c	[PATCH] Numerous fixes to kernel-doc info in source files.	18 years ago
migrate.c	[PATCH] Page migration: Fix vma flag checking	18 years ago
mincore.c	[PATCH] mincore: vma crossing fix	18 years ago
mlock.c	…
mmap.c	[PATCH] Bug in MM_RB debugging	18 years ago
mmzone.c	…
mprotect.c	…
mremap.c	…
msync.c	…
nommu.c	…
oom_kill.c	…
page-writeback.c	[PATCH] throttle_vm_writeout(): don't loop on GFP_NOFS and GFP_NOIO allocations	18 years ago
page_alloc.c	[PATCH] Rename PG_checked to PG_owner_priv_1	18 years ago
page_io.c	…
pdflush.c	…
prio_tree.c	…
readahead.c	[PATCH] Drop __get_zone_counts()	18 years ago
rmap.c	[PATCH] adapt page_lock_anon_vma() to PREEMPT_RCU	18 years ago
shmem.c	[PATCH] shmem and simple const super_operations	18 years ago
shmem_acl.c	…
slab.c	[PATCH] kernel-doc fixes for 2.6.20-git15 (non-drivers)	18 years ago
slob.c	…
sparse.c	…
swap.c	…
swap_state.c	…
swapfile.c	…
thrash.c	…
tiny-shmem.c	[PATCH] mm/{,tiny-}shmem.c cleanups	18 years ago
truncate.c	[PATCH] VM: invalidate_inode_pages2_range() should not exit early	18 years ago
util.c	…
vmalloc.c	[PATCH] Numerous fixes to kernel-doc info in source files.	18 years ago
vmscan.c	[PATCH] throttle_vm_writeout(): don't loop on GFP_NOFS and GFP_NOIO allocations	18 years ago
vmstat.c	[PATCH] optional ZONE_DMA: optional ZONE_DMA in the VM	18 years ago