linux-stable.git/fs/ubifs, branch linux-4.2.y

UBIFS: Kill unneeded locking in ubifs_init_security

2015-10-22T21:49:31+00:00

commit cf6f54e3f133229f02a90c04fe0ff9dd9d3264b4 upstream.

Fixes the following lockdep splat:
[    1.244527] =============================================
[    1.245193] [ INFO: possible recursive locking detected ]
[    1.245193] 4.2.0-rc1+ #37 Not tainted
[    1.245193] ---------------------------------------------
[    1.245193] cp/742 is trying to acquire lock:
[    1.245193]  (&sb->s_type->i_mutex_key#9){+.+.+.}, at: [] ubifs_init_security+0x29/0xb0
[    1.245193]
[    1.245193] but task is already holding lock:
[    1.245193]  (&sb->s_type->i_mutex_key#9){+.+.+.}, at: [] path_openat+0x3af/0x1280
[    1.245193]
[    1.245193] other info that might help us debug this:
[    1.245193]  Possible unsafe locking scenario:
[    1.245193]
[    1.245193]        CPU0
[    1.245193]        ----
[    1.245193]   lock(&sb->s_type->i_mutex_key#9);
[    1.245193]   lock(&sb->s_type->i_mutex_key#9);
[    1.245193]
[    1.245193]  *** DEADLOCK ***
[    1.245193]
[    1.245193]  May be due to missing lock nesting notation
[    1.245193]
[    1.245193] 2 locks held by cp/742:
[    1.245193]  #0:  (sb_writers#5){.+.+.+}, at: [] mnt_want_write+0x1f/0x50
[    1.245193]  #1:  (&sb->s_type->i_mutex_key#9){+.+.+.}, at: [] path_openat+0x3af/0x1280
[    1.245193]
[    1.245193] stack backtrace:
[    1.245193] CPU: 2 PID: 742 Comm: cp Not tainted 4.2.0-rc1+ #37
[    1.245193] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.7.5-0-ge51488c-20140816_022509-build35 04/01/2014
[    1.245193]  ffffffff8252d530 ffff88007b023a38 ffffffff814f6f49 ffffffff810b56c5
[    1.245193]  ffff88007c30cc80 ffff88007b023af8 ffffffff810a150d ffff88007b023a68
[    1.245193]  000000008101302a ffff880000000000 00000008f447e23f ffffffff8252d500
[    1.245193] Call Trace:
[    1.245193]  [] dump_stack+0x4c/0x65
[    1.245193]  [] ? console_unlock+0x1c5/0x510
[    1.245193]  [] __lock_acquire+0x1a6d/0x1ea0
[    1.245193]  [] ? __lock_is_held+0x58/0x80
[    1.245193]  [] lock_acquire+0xd3/0x270
[    1.245193]  [] ? ubifs_init_security+0x29/0xb0
[    1.245193]  [] mutex_lock_nested+0x6b/0x3a0
[    1.245193]  [] ? ubifs_init_security+0x29/0xb0
[    1.245193]  [] ? ubifs_init_security+0x29/0xb0
[    1.245193]  [] ubifs_init_security+0x29/0xb0
[    1.245193]  [] ubifs_create+0xa6/0x1f0
[    1.245193]  [] ? path_openat+0x3af/0x1280
[    1.245193]  [] vfs_create+0x95/0xc0
[    1.245193]  [] path_openat+0x7cc/0x1280
[    1.245193]  [] ? __lock_acquire+0x543/0x1ea0
[    1.245193]  [] ? sched_clock_cpu+0x90/0xc0
[    1.245193]  [] ? calc_global_load_tick+0x60/0x90
[    1.245193]  [] ? sched_clock_cpu+0x90/0xc0
[    1.245193]  [] ? __alloc_fd+0xaf/0x180
[    1.245193]  [] do_filp_open+0x75/0xd0
[    1.245193]  [] ? _raw_spin_unlock+0x26/0x40
[    1.245193]  [] ? __alloc_fd+0xaf/0x180
[    1.245193]  [] do_sys_open+0x129/0x200
[    1.245193]  [] SyS_open+0x19/0x20
[    1.245193]  [] entry_SYSCALL_64_fastpath+0x12/0x6f

While the lockdep splat is a false positive, becuase path_openat holds i_mutex
of the parent directory and ubifs_init_security() tries to acquire i_mutex
of a new inode, it reveals that taking i_mutex in ubifs_init_security() is
in vain because it is only being called in the inode allocation path
and therefore nobody else can see the inode yet.

Reported-and-tested-by: Boris Brezillon 
Reviewed-and-tested-by: Dongsheng Yang 
Signed-off-by: Richard Weinberger 
Signed-off-by: dedekind1@gmail.com
Signed-off-by: Greg Kroah-Hartman

Merge tag 'upstream-4.2-rc1' of git://git.infradead.org/linux-ubifs

2015-06-25T21:11:34+00:00

Pull UBI/UBIFS updates from Richard Weinberger:
 "Minor fixes for UBI and UBIFS"

* tag 'upstream-4.2-rc1' of git://git.infradead.org/linux-ubifs:
  UBI: Remove unnecessary `\'
  UBI: Use static class and attribute groups
  UBI: add a helper function for updatting on-flash layout volumes
  UBI: Fastmap: Do not add vol if it already exists
  UBI: Init vol->reserved_pebs by assignment
  UBI: Fastmap: Rename variables to make them meaningful
  UBI: Fastmap: Remove unnecessary `\'
  UBI: Fastmap: Use max() to get the larger value
  ubifs: fix to check error code of register_shrinker
  UBI: block: Dynamically allocate minor numbers

ubifs: fix to check error code of register_shrinker

2015-06-02T09:41:38+00:00

register_shrinker() in ubifs_init() can fail due to fail to call kzalloc.
This patch fixes to check the return value of register_shrinker, otherwise
our shrinker may be unregistered after ubifs initialized successfully.

Signed-off-by: Chao Yu 
Signed-off-by: Artem Bityutskiy 
Signed-off-by: Richard Weinberger

ubifs: switch to simple_follow_link()

2015-05-11T02:18:25+00:00

Signed-off-by: Al Viro

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2015-04-27T00:22:07+00:00

Pull fourth vfs update from Al Viro:
 "d_inode() annotations from David Howells (sat in for-next since before
  the beginning of merge window) + four assorted fixes"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  RCU pathwalk breakage when running into a symlink overmounting something
  fix I_DIO_WAKEUP definition
  direct-io: only inc/dec inode->i_dio_count for file systems
  fs/9p: fix readdir()
  VFS: assorted d_backing_inode() annotations
  VFS: fs/inode.c helpers: d_inode() annotations
  VFS: fs/cachefiles: d_backing_inode() annotations
  VFS: fs library helpers: d_inode() annotations
  VFS: assorted weird filesystems: d_inode() annotations
  VFS: normal filesystems (and lustre): d_inode() annotations
  VFS: security/: d_inode() annotations
  VFS: security/: d_backing_inode() annotations
  VFS: net/: d_inode() annotations
  VFS: net/unix: d_backing_inode() annotations
  VFS: kernel/: d_inode() annotations
  VFS: audit: d_backing_inode() annotations
  VFS: Fix up some ->d_inode accesses in the chelsio driver
  VFS: Cachefiles should perform fs modifications on the top layer only
  VFS: AF_UNIX sockets should call mknod on the top layer only

Merge tag 'upstream-4.1-rc1' of git://git.infradead.org/linux-ubifs

2015-04-15T20:43:40+00:00

Pull UBI/UBIFS updates from Richard Weinberger:
 "This pull request includes the following UBI/UBIFS changes:

   - powercut emulation for UBI
   - a huge update to UBI Fastmap
   - cleanups and bugfixes all over UBI and UBIFS"

* tag 'upstream-4.1-rc1' of git://git.infradead.org/linux-ubifs: (50 commits)
  UBI: power cut emulation for testing
  UBIFS: fix output format of INUM_WATERMARK
  UBI: Fastmap: Fall back to scanning mode after ECC error
  UBI: Fastmap: Remove is_fm_block()
  UBI: Fastmap: Add blank line after declarations
  UBI: Fastmap: Remove else after return.
  UBI: Fastmap: Introduce may_reserve_for_fm()
  UBI: Fastmap: Introduce ubi_fastmap_init()
  UBI: Fastmap: Wire up WL accessor functions
  UBI: Add accessor functions for WL data structures
  UBI: Move fastmap specific functions out of wl.c
  UBI: Fastmap: Add new module parameter fm_debug
  UBI: Fastmap: Make self_check_eba() depend on fastmap self checking
  UBI: Fastmap: Add self check to detect absent PEBs
  UBI: Fix stale pointers in ubi->lookuptbl
  UBI: Fastmap: Enhance fastmap checking
  UBI: Add initial support for fastmap self checks
  UBI: Fastmap: Rework fastmap error paths
  UBI: Fastmap: Prepare for variable sized fastmaps
  UBI: Fastmap: Locking updates
  ...

VFS: normal filesystems (and lustre): d_inode() annotations

2015-04-15T19:06:57+00:00

that's the bulk of filesystem drivers dealing with inodes of their own

Signed-off-by: David Howells 
Signed-off-by: Al Viro

UBIFS: fix output format of INUM_WATERMARK

2015-04-13T10:37:31+00:00

The INUM_WATERMARK is a unsigned 32bit value, `%d' prints it as negatave:
[  103.682255] UBIFS warning (ubi0:0 pid 691): ubifs_new_inode: running out of inode numbers (current 122763, max -256)

Fix it as:
[  154.422940] UBIFS warning (ubi0:0 pid 688): ubifs_new_inode: running out of inode numbers (current 122765, max 4294967040)

Signed-off-by: Sheng Yong 
Signed-off-by: Artem Bityutskiy

make new_sync_{read,write}() static

2015-04-12T02:29:40+00:00

All places outside of core VFS that checked ->read and ->write for being NULL or
called the methods directly are gone now, so NULL {read,write} with non-NULL
{read,write}_iter will do the right thing in all cases.

Signed-off-by: Al Viro

fs: move struct kiocb to fs.h

2015-03-26T00:28:11+00:00

struct kiocb now is a generic I/O container, so move it to fs.h.
Also do a #include diet for aio.h while we're at it.

Signed-off-by: Christoph Hellwig 
Signed-off-by: Al Viro