https://github.com/torvalds/linux
Revision 914ee295af418e936ec20a08c1663eaabe4cd07a authored by Xin Zhong on 09 December 2010, 09:30:14 UTC, committed by Chris Mason on 10 December 2010, 21:29:10 UTC
This problem is found in meego testing: http://bugs.meego.com/show_bug.cgi?id=6672 A file in btrfs is mmaped and the mmaped buffer is passed to pwrite to write to the same page of the same file. In btrfs_file_aio_write(), the pages is locked by prepare_pages(). So when btrfs_copy_from_user() is called, page fault happens and the same page needs to be locked again in filemap_fault(). The fix is to move iov_iter_fault_in_readable() before prepage_pages() to make page fault happen before pages are locked. And also disable page fault in critical region in btrfs_copy_from_user(). Reviewed-by: Yan, Zheng<zheng.z.yan@intel.com> Signed-off-by: Zhong, Xin <xin.zhong@intel.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
1 parent f106e82
Tip revision: 914ee295af418e936ec20a08c1663eaabe4cd07a authored by Xin Zhong on 09 December 2010, 09:30:14 UTC
Btrfs: pwrite blocked when writing from the mmaped buffer of the same page
Btrfs: pwrite blocked when writing from the mmaped buffer of the same page
Tip revision: 914ee29
| File | Mode | Size |
|---|---|---|
| 9p | ||
| adfs | ||
| affs | ||
| afs | ||
| autofs | ||
| autofs4 | ||
| befs | ||
| bfs | ||
| btrfs | ||
| cachefiles | ||
| ceph | ||
| cifs | ||
| coda | ||
| configfs | ||
| cramfs | ||
| debugfs | ||
| devpts | ||
| dlm | ||
| ecryptfs | ||
| efs | ||
| exofs | ||
| exportfs | ||
| ext2 | ||
| ext3 | ||
| ext4 | ||
| fat | ||
| freevxfs | ||
| fscache | ||
| fuse | ||
| gfs2 | ||
| hfs | ||
| hfsplus | ||
| hostfs | ||
| hpfs | ||
| hppfs | ||
| hugetlbfs | ||
| isofs | ||
| jbd | ||
| jbd2 | ||
| jffs2 | ||
| jfs | ||
| lockd | ||
| logfs | ||
| minix | ||
| ncpfs | ||
| nfs | ||
| nfs_common | ||
| nfsd | ||
| nilfs2 | ||
| nls | ||
| notify | ||
| ntfs | ||
| ocfs2 | ||
| omfs | ||
| openpromfs | ||
| partitions | ||
| proc | ||
| qnx4 | ||
| quota | ||
| ramfs | ||
| reiserfs | ||
| romfs | ||
| smbfs | ||
| squashfs | ||
| sysfs | ||
| sysv | ||
| ubifs | ||
| udf | ||
| ufs | ||
| xfs | ||
| Kconfig | -rw-r--r-- | 5.4 KB |
| Kconfig.binfmt | -rw-r--r-- | 6.4 KB |
| Makefile | -rw-r--r-- | 4.1 KB |
| aio.c | -rw-r--r-- | 46.5 KB |
| anon_inodes.c | -rw-r--r-- | 6.4 KB |
| attr.c | -rw-r--r-- | 6.6 KB |
| bad_inode.c | -rw-r--r-- | 7.7 KB |
| binfmt_aout.c | -rw-r--r-- | 12.4 KB |
| binfmt_elf.c | -rw-r--r-- | 53.7 KB |
| binfmt_elf_fdpic.c | -rw-r--r-- | 48.7 KB |
| binfmt_em86.c | -rw-r--r-- | 2.8 KB |
| binfmt_flat.c | -rw-r--r-- | 26.8 KB |
| binfmt_misc.c | -rw-r--r-- | 15.1 KB |
| binfmt_script.c | -rw-r--r-- | 2.8 KB |
| binfmt_som.c | -rw-r--r-- | 7.4 KB |
| bio-integrity.c | -rw-r--r-- | 21.0 KB |
| bio.c | -rw-r--r-- | 39.2 KB |
| block_dev.c | -rw-r--r-- | 42.6 KB |
| buffer.c | -rw-r--r-- | 87.5 KB |
| char_dev.c | -rw-r--r-- | 13.9 KB |
| compat.c | -rw-r--r-- | 56.2 KB |
| compat_binfmt_elf.c | -rw-r--r-- | 3.5 KB |
| compat_ioctl.c | -rw-r--r-- | 48.4 KB |
| dcache.c | -rw-r--r-- | 62.1 KB |
| dcookies.c | -rw-r--r-- | 6.8 KB |
| direct-io.c | -rw-r--r-- | 35.0 KB |
| drop_caches.c | -rw-r--r-- | 1.3 KB |
| eventfd.c | -rw-r--r-- | 10.9 KB |
| eventpoll.c | -rw-r--r-- | 38.8 KB |
| exec.c | -rw-r--r-- | 47.5 KB |
| fcntl.c | -rw-r--r-- | 17.5 KB |
| fifo.c | -rw-r--r-- | 3.2 KB |
| file.c | -rw-r--r-- | 11.7 KB |
| file_table.c | -rw-r--r-- | 12.1 KB |
| filesystems.c | -rw-r--r-- | 6.3 KB |
| fs-writeback.c | -rw-r--r-- | 32.0 KB |
| fs_struct.c | -rw-r--r-- | 3.2 KB |
| generic_acl.c | -rw-r--r-- | 4.5 KB |
| inode.c | -rw-r--r-- | 40.6 KB |
| internal.h | -rw-r--r-- | 2.4 KB |
| ioctl.c | -rw-r--r-- | 15.7 KB |
| ioprio.c | -rw-r--r-- | 5.2 KB |
| libfs.c | -rw-r--r-- | 24.1 KB |
| locks.c | -rw-r--r-- | 57.7 KB |
| mbcache.c | -rw-r--r-- | 16.6 KB |
| mpage.c | -rw-r--r-- | 20.0 KB |
| namei.c | -rw-r--r-- | 70.5 KB |
| namespace.c | -rw-r--r-- | 59.1 KB |
| nfsctl.c | -rw-r--r-- | 2.4 KB |
| no-block.c | -rw-r--r-- | 663 bytes |
| open.c | -rw-r--r-- | 23.7 KB |
| pipe.c | -rw-r--r-- | 27.8 KB |
| pnode.c | -rw-r--r-- | 9.3 KB |
| pnode.h | -rw-r--r-- | 1.1 KB |
| posix_acl.c | -rw-r--r-- | 8.4 KB |
| read_write.c | -rw-r--r-- | 20.4 KB |
| read_write.h | -rw-r--r-- | 542 bytes |
| readdir.c | -rw-r--r-- | 6.9 KB |
| select.c | -rw-r--r-- | 24.2 KB |
| seq_file.c | -rw-r--r-- | 17.9 KB |
| signalfd.c | -rw-r--r-- | 7.2 KB |
| splice.c | -rw-r--r-- | 47.2 KB |
| stack.c | -rw-r--r-- | 2.7 KB |
| stat.c | -rw-r--r-- | 10.5 KB |
| statfs.c | -rw-r--r-- | 5.2 KB |
| super.c | -rw-r--r-- | 25.5 KB |
| sync.c | -rw-r--r-- | 9.9 KB |
| timerfd.c | -rw-r--r-- | 6.5 KB |
| utimes.c | -rw-r--r-- | 5.6 KB |
| xattr.c | -rw-r--r-- | 15.6 KB |
| xattr_acl.c | -rw-r--r-- | 2.3 KB |
Computing file changes ...
