WSL2-Linux-Kernel/fs/9p
Al Viro 4ad7862844 9p: ->evict_inode() should kick out ->i_data, not ->i_mapping
For block devices the pagecache is associated with the inode
on bdevfs, not with the aliasing ones on the mountable filesystems.
The latter have its own ->i_data empty and ->i_mapping pointing
to the (unique per major/minor) bdevfs inode.  That guarantees
cache coherence between all block device inodes with the same
device number.

Eviction of an alias inode has no business trying to evict the
pages belonging to bdevfs one; moreover, ->i_mapping is only
safe to access when the thing is opened.  At the time of
->evict_inode() the victim is definitely *not* opened.  We are
about to kill the address space embedded into struct inode
(inode->i_data) and that's what we need to empty of any pages.

9p instance tries to empty inode->i_mapping instead, which is
both unsafe and bogus - if we have several device nodes with
the same device number in different places, closing one of them
should not try to empty the (shared) page cache.

Fortunately, other instances in the tree are OK; they are
evicting from &inode->i_data instead, as 9p one should.

Cc: stable@vger.kernel.org # v2.6.32+, ones prior to 2.6.36 need only half of that
Reported-by: "Suzuki K. Poulose" <Suzuki.Poulose@arm.com>
Tested-by: "Suzuki K. Poulose" <Suzuki.Poulose@arm.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-12-08 14:51:16 -05:00
..
Kconfig fs/9p: xattr: add trusted and security namespaces 2013-07-07 22:02:18 -05:00
Makefile 9p: xattr simplifications 2015-11-13 20:34:33 -05:00
acl.c 9p: xattr simplifications 2015-11-13 20:34:33 -05:00
acl.h 9p: switch v9fs_set_create_acl() to inode+fid, do it before d_instantiate() 2013-02-26 02:46:07 -05:00
cache.c 9p: remove unused 'p9_fid' struct pointer 2013-11-23 16:10:31 -06:00
cache.h fs: 9p: cache.h: Add #define of include guard 2015-11-11 02:19:50 -05:00
fid.c 9p: switch to %p[dD] 2014-10-09 02:39:04 -04:00
fid.h 9p: v9fs_fid_add() can't fail now 2013-02-28 01:18:14 -05:00
v9fs.c 9p: remove unused option Opt_trans 2015-08-23 14:21:16 -05:00
v9fs.h 9p: don't bother with __getname() in ->follow_link() 2015-05-10 22:18:19 -04:00
v9fs_vfs.h 9p: switch p9_client_read() to passing struct iov_iter * 2015-04-11 22:28:27 -04:00
vfs_addr.c 9p: patches for 4.1 merge window 2015-04-18 17:45:30 -04:00
vfs_dentry.c VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
vfs_dir.c fs/9p: fix readdir() 2015-04-24 15:45:03 -04:00
vfs_file.c Merge branch 'akpm' (patches from Andrew) 2015-11-05 23:10:54 -08:00
vfs_inode.c 9p: ->evict_inode() should kick out ->i_data, not ->i_mapping 2015-12-08 14:51:16 -05:00
vfs_inode_dotl.c fs/9p: remove unnecessary new_valid_dev() checks 2015-11-09 15:11:24 -08:00
vfs_super.c v9fs: fix error handling in v9fs_session_init() 2015-06-08 09:05:06 -06:00
xattr.c 9p: xattr simplifications 2015-11-13 20:34:33 -05:00
xattr.h 9p: xattr simplifications 2015-11-13 20:34:33 -05:00