linux-toradex.git/fs/pstore, branch v4.9.91

pstore: Use dynamic spinlock initializer

2017-08-07T01:59:43+00:00

commit e9a330c4289f2ba1ca4bf98c2b430ab165a8931b upstream.

The per-prz spinlock should be using the dynamic initializer so that
lockdep can correctly track it. Without this, under lockdep, we get a
warning at boot that the lock is in non-static memory.

Fixes: 109704492ef6 ("pstore: Make spinlock per zone instead of global")
Fixes: 76d5692a5803 ("pstore: Correctly initialize spinlock and flags")
Signed-off-by: Kees Cook 
Signed-off-by: Greg Kroah-Hartman

pstore: Correctly initialize spinlock and flags

2017-08-07T01:59:43+00:00

commit 76d5692a58031696e282384cbd893832bc92bd76 upstream.

The ram backend wasn't always initializing its spinlock correctly. Since
it was coming from kzalloc memory, though, it was harmless on
architectures that initialize unlocked spinlocks to 0 (at least x86 and
ARM). This also fixes a possibly ignored flag setting too.

When running under CONFIG_DEBUG_SPINLOCK, the following Oops was visible:

[    0.760836] persistent_ram: found existing buffer, size 29988, start 29988
[    0.765112] persistent_ram: found existing buffer, size 30105, start 30105
[    0.769435] persistent_ram: found existing buffer, size 118542, start 118542
[    0.785960] persistent_ram: found existing buffer, size 0, start 0
[    0.786098] persistent_ram: found existing buffer, size 0, start 0
[    0.786131] pstore: using zlib compression
[    0.790716] BUG: spinlock bad magic on CPU#0, swapper/0/1
[    0.790729]  lock: 0xffffffc0d1ca9bb0, .magic: 00000000, .owner: /-1, .owner_cpu: 0
[    0.790742] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.10.0-rc2+ #913
[    0.790747] Hardware name: Google Kevin (DT)
[    0.790750] Call trace:
[    0.790768] [] dump_backtrace+0x0/0x2bc
[    0.790780] [] show_stack+0x20/0x28
[    0.790794] [] dump_stack+0xa4/0xcc
[    0.790809] [] spin_dump+0xe0/0xf0
[    0.790821] [] spin_bug+0x30/0x3c
[    0.790834] [] do_raw_spin_lock+0x50/0x1b8
[    0.790846] [] _raw_spin_lock_irqsave+0x54/0x6c
[    0.790862] [] buffer_size_add+0x48/0xcc
[    0.790875] [] persistent_ram_write+0x60/0x11c
[    0.790888] [] ramoops_pstore_write_buf+0xd4/0x2a4
[    0.790900] [] pstore_console_write+0xf0/0x134
[    0.790912] [] console_unlock+0x48c/0x5e8
[    0.790923] [] register_console+0x3b0/0x4d4
[    0.790935] [] pstore_register+0x1a8/0x234
[    0.790947] [] ramoops_probe+0x6b8/0x7d4
[    0.790961] [] platform_drv_probe+0x7c/0xd0
[    0.790972] [] driver_probe_device+0x1b4/0x3bc
[    0.790982] [] __device_attach_driver+0xc8/0xf4
[    0.790996] [] bus_for_each_drv+0xb4/0xe4
[    0.791006] [] __device_attach+0xd0/0x158
[    0.791016] [] device_initial_probe+0x24/0x30
[    0.791026] [] bus_probe_device+0x50/0xe4
[    0.791038] [] device_add+0x3a4/0x76c
[    0.791051] [] of_device_add+0x74/0x84
[    0.791062] [] of_platform_device_create_pdata+0xc0/0x100
[    0.791073] [] of_platform_device_create+0x34/0x40
[    0.791086] [] of_platform_default_populate_init+0x58/0x78
[    0.791097] [] do_one_initcall+0x88/0x160
[    0.791109] [] kernel_init_freeable+0x264/0x31c
[    0.791123] [] kernel_init+0x18/0x11c
[    0.791133] [] ret_from_fork+0x10/0x50
[    0.793717] console [pstore-1] enabled
[    0.797845] pstore: Registered ramoops as persistent store backend
[    0.804647] ramoops: attached 0x100000@0xf7edc000, ecc: 0/0

Fixes: 663deb47880f ("pstore: Allow prz to control need for locking")
Fixes: 109704492ef6 ("pstore: Make spinlock per zone instead of global")
Reported-by: Brian Norris 
Signed-off-by: Kees Cook 
Signed-off-by: Greg Kroah-Hartman

pstore: Allow prz to control need for locking

2017-08-07T01:59:43+00:00

commit 663deb47880f2283809669563c5a52ac7c6aef1a upstream.

In preparation of not locking at all for certain buffers depending on if
there's contention, make locking optional depending on the initialization
of the prz.

Signed-off-by: Joel Fernandes 
[kees: moved locking flag into prz instead of via caller arguments]
Signed-off-by: Kees Cook 
Signed-off-by: Greg Kroah-Hartman

pstore: Make spinlock per zone instead of global

2017-08-07T01:59:39+00:00

commit 109704492ef637956265ec2eb72ae7b3b39eb6f4 upstream.

Currently pstore has a global spinlock for all zones. Since the zones
are independent and modify different areas of memory, there's no need
to have a global lock, so we should use a per-zone lock as introduced
here. Also, when ramoops's ftrace use-case has a FTRACE_PER_CPU flag
introduced later, which splits the ftrace memory area into a single zone
per CPU, it will eliminate the need for locking. In preparation for this,
make the locking optional.

Signed-off-by: Joel Fernandes 
[kees: updated commit message]
Signed-off-by: Kees Cook 
Cc: Leo Yan 
Signed-off-by: Greg Kroah-Hartman

pstore: Shut down worker when unregistering

2017-05-20T12:28:42+00:00

commit 6330d5534786d5315d56d558aa6d20740f97d80a upstream.

When built as a module and running with update_ms >= 0, pstore will Oops
during module unload since the work timer is still running. This makes sure
the worker is stopped before unloading.

Signed-off-by: Kees Cook 
Signed-off-by: Greg Kroah-Hartman

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

2016-10-11T03:16:43+00:00

Pull more vfs updates from Al Viro:
 ">rename2() work from Miklos + current_time() from Deepa"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  fs: Replace current_fs_time() with current_time()
  fs: Replace CURRENT_TIME_SEC with current_time() for inode timestamps
  fs: Replace CURRENT_TIME with current_time() for inode timestamps
  fs: proc: Delete inode time initializations in proc_alloc_inode()
  vfs: Add current_time() api
  vfs: add note about i_op->rename changes to porting
  fs: rename "rename2" i_op to "rename"
  vfs: remove unused i_op->rename
  fs: make remaining filesystems use .rename2
  libfs: support RENAME_NOREPLACE in simple_rename()
  fs: support RENAME_NOREPLACE for local filesystems
  ncpfs: fix unused variable warning

fs: Replace CURRENT_TIME with current_time() for inode timestamps

2016-09-28T01:06:21+00:00

CURRENT_TIME macro is not appropriate for filesystems as it
doesn't use the right granularity for filesystem timestamps.
Use current_time() instead.

CURRENT_TIME is also not y2038 safe.

This is also in preparation for the patch that transitions
vfs timestamps to use 64 bit time and hence make them
y2038 safe. As part of the effort current_time() will be
extended to do range checks. Hence, it is necessary for all
file system timestamps to use current_time(). Also,
current_time() will be transitioned along with vfs to be
y2038 safe.

Note that whenever a single call to current_time() is used
to change timestamps in different inodes, it is because they
share the same time granularity.

Signed-off-by: Deepa Dinamani 
Reviewed-by: Arnd Bergmann 
Acked-by: Felipe Balbi 
Acked-by: Steven Whitehouse 
Acked-by: Ryusuke Konishi 
Acked-by: David Sterba 
Signed-off-by: Al Viro

ramoops: move spin_lock_init after kmalloc error checking

2016-09-08T22:01:13+00:00

If cxt->pstore.buf allocated failed, no need to initialize
cxt->pstore.buf_lock. So this patch moves spin_lock_init() after the
error checking.

Signed-off-by: Geliang Tang 
Signed-off-by: Kees Cook

pstore/ram: Use memcpy_fromio() to save old buffer

2016-09-08T22:01:12+00:00

The ramoops buffer may be mapped as either I/O memory or uncached
memory.  On ARM64, this results in a device-type (strongly-ordered)
mapping.  Since unnaligned accesses to device-type memory will
generate an alignment fault (regardless of whether or not strict
alignment checking is enabled), it is not safe to use memcpy().
memcpy_fromio() is guaranteed to only use aligned accesses, so use
that instead.

Signed-off-by: Andrew Bresticker 
Signed-off-by: Enric Balletbo Serra 
Reviewed-by: Puneet Kumar 
Signed-off-by: Kees Cook 
Cc: stable@vger.kernel.org

pstore/ram: Use memcpy_toio instead of memcpy

2016-09-08T22:01:11+00:00

persistent_ram_update uses vmap / iomap based on whether the buffer is in
memory region or reserved region. However, both map it as non-cacheable
memory. For armv8 specifically, non-cacheable mapping requests use a
memory type that has to be accessed aligned to the request size. memcpy()
doesn't guarantee that.

Signed-off-by: Furquan Shaikh 
Signed-off-by: Enric Balletbo Serra 
Reviewed-by: Aaron Durbin 
Reviewed-by: Olof Johansson 
Tested-by: Furquan Shaikh 
Signed-off-by: Kees Cook 
Cc: stable@vger.kernel.org