Revision ad576e63e0c8b274a8558b8e05a6d0526e804dc0 authored by Nick Piggin on 05 May 2005, 23:15:46 UTC, committed by Linus Torvalds on 05 May 2005, 23:36:40 UTC
When running fsstress -v -d $DIR/tmp -n 1000 -p 1000 -l 2 on an ext2 filesystem with 1024 byte block size, on SMP i386 with 4096 byte page size over loopback to an image file on a tmpfs filesystem, I would very quickly hit BUG_ON(!buffer_async_write(bh)); in fs/buffer.c:end_buffer_async_write It seems that more than one request would be submitted for a given bh at a time. What would happen is the following: 2 threads doing __mpage_writepages on the same page. Thread 1 - lock the page first, and enter __block_write_full_page. Thread 1 - (eg.) mark_buffer_async_write on the first 2 buffers. Thread 1 - set page writeback, unlock page. Thread 2 - lock page, wait on page writeback Thread 1 - submit_bh on the first 2 buffers. => both requests complete, none of the page buffers are async_write, end_page_writeback is called. Thread 2 - wakes up. enters __block_write_full_page. Thread 2 - mark_buffer_async_write on (eg.) the last buffer Thread 1 - finds the last buffer has async_write set, submit_bh on that. Thread 2 - submit_bh on the last buffer. => oops. So change __block_write_full_page to explicitly keep track of the last bh we need to issue, so we don't touch anything after issuing the last request. Signed-off-by: Nick Piggin <nickpiggin@yahoo.com.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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AUTHORS | -rw-r--r-- | 2.2 KB |
CHANGES | -rw-r--r-- | 27.6 KB |
Makefile | -rw-r--r-- | 296 bytes |
README | -rw-r--r-- | 25.5 KB |
TODO | -rw-r--r-- | 4.6 KB |
asn1.c | -rw-r--r-- | 13.6 KB |
cifs_debug.c | -rw-r--r-- | 18.5 KB |
cifs_debug.h | -rw-r--r-- | 2.0 KB |
cifs_fs_sb.h | -rw-r--r-- | 1.5 KB |
cifs_unicode.c | -rw-r--r-- | 2.2 KB |
cifs_unicode.h | -rw-r--r-- | 7.9 KB |
cifs_uniupr.h | -rw-r--r-- | 12.6 KB |
cifsencrypt.c | -rw-r--r-- | 6.5 KB |
cifsencrypt.h | -rw-r--r-- | 1.4 KB |
cifsfs.c | -rw-r--r-- | 24.2 KB |
cifsfs.h | -rw-r--r-- | 4.2 KB |
cifsglob.h | -rw-r--r-- | 14.7 KB |
cifspdu.h | -rw-r--r-- | 60.5 KB |
cifsproto.h | -rw-r--r-- | 12.6 KB |
cifssmb.c | -rw-r--r-- | 131.0 KB |
connect.c | -rw-r--r-- | 99.3 KB |
dir.c | -rw-r--r-- | 12.2 KB |
fcntl.c | -rw-r--r-- | 3.7 KB |
file.c | -rw-r--r-- | 44.9 KB |
inode.c | -rw-r--r-- | 34.3 KB |
ioctl.c | -rw-r--r-- | 2.9 KB |
link.c | -rw-r--r-- | 8.7 KB |
md4.c | -rw-r--r-- | 4.5 KB |
md5.c | -rw-r--r-- | 10.6 KB |
md5.h | -rw-r--r-- | 1.1 KB |
misc.c | -rw-r--r-- | 19.1 KB |
netmisc.c | -rw-r--r-- | 36.1 KB |
nterr.c | -rw-r--r-- | 33.5 KB |
nterr.h | -rw-r--r-- | 29.8 KB |
ntlmssp.h | -rw-r--r-- | 4.0 KB |
readdir.c | -rw-r--r-- | 28.1 KB |
rfc1002pdu.h | -rw-r--r-- | 2.9 KB |
smbdes.c | -rw-r--r-- | 9.9 KB |
smbencrypt.c | -rw-r--r-- | 7.6 KB |
smberr.h | -rw-r--r-- | 7.2 KB |
transport.c | -rw-r--r-- | 17.2 KB |
xattr.c | -rw-r--r-- | 10.3 KB |
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