linux-stable.git/drivers/base/firmware_class.c, branch linux-3.13.y

PM / hibernate: Fix restore hang in freeze_processes()

2014-03-07T06:06:29+00:00

commit f8d5b9e9e5372f0deb7bc1ab1088a9b60b0a793d upstream.

During restore, pm_notifier chain are called with
PM_RESTORE_PREPARE.  The firmware_class driver handler
fw_pm_notify does not have a handler for this.  As a result,
it keeps a reader on the kmod.c umhelper_sem.  During
freeze_processes, the call to __usermodehelper_disable tries to
take a write lock on this semaphore and hangs waiting.

Signed-off-by: Sebastian Capella 
Acked-by: Ming Lei 
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Greg Kroah-Hartman

firmware: Be a bit more verbose about direct firmware loading failure

2013-09-26T22:35:30+00:00

The direct firmware loading interface is a bit quiet about failures.  Failures
that occur during loading are masked if firmware exists in multiple locations,
and may be masked entirely in the event that we fall back to the user mode
helper code.  It would be nice to see some of the more unexpected errors get
logged, so in the event that you expect the direct firmware loader to work (like
if CONFIG_FW_LOADER_USER_HELPER is enabled), and something goes wrong, you can
figure out what happened.

Signed-off-by: Neil Horman 
Acked-by: Ming Lei 
Signed-off-by: Greg Kroah-Hartman

firmware loader: fix pending_fw_head list corruption

2013-08-30T19:04:27+00:00

Got the following oops just before reboot:

Unable to handle kernel NULL pointer dereference at virtual address 00000000
[<8028d300>] (__list_del_entry+0x44/0xac)
[<802e3320>] (__fw_load_abort.part.13+0x1c/0x50)
[<802e337c>] (fw_shutdown_notify+0x28/0x50)
[<80034f80>] (notifier_call_chain.isra.1+0x5c/0x9c)
[<800350ec>] (__blocking_notifier_call_chain+0x44/0x58)
[<80035114>] (blocking_notifier_call_chain+0x14/0x18)
[<80035d64>] (kernel_restart_prepare+0x14/0x38)
[<80035d94>] (kernel_restart+0xc/0x50)

The following race condition triggers here:

  _request_firmware_load()
  device_create_file(...)
  kobject_uevent(...)
  (schedule)
                                       (resume)
                                       firmware_loading_store(1)
                                       firmware_loading_store(0)
                                       list_del_init(&buf->pending_list)
                                       (schedule)
  (resume)
  list_add(&buf->pending_list, &pending_fw_head);
  wait_for_completion(&buf->completion);

causing an oops later when walking pending_list after the firmware has
been released.

The proposed fix is to move the list_add() before sysfs attribute
creation.

Signed-off-by: Maxime Bizon 
Acked-by: Ming Lei 
Cc: stable 
Signed-off-by: Greg Kroah-Hartman

driver core: firmware: use __ATTR_RW()

2013-08-24T00:08:48+00:00

Use __ATTR_RW() instead of __ATTR() to make it more obvious what the
type of attribute is being created.

Signed-off-by: Greg Kroah-Hartman

firmware loader: fix another compile warning with PM_SLEEP unset

2013-06-26T04:04:22+00:00

This patch fixes another compiling warning with PM_SLEEP unset:

drivers/base/firmware_class.c:221:29: warning: 'fw_lookup_buf' defined
but not used [-Wunused-function]

This time I do build kernel with both PM_SLEEP set and unset, and no
warning found any more with the patch.

Reported-by: Stephen Rothwell 
Signed-off-by: Ming Lei 
Signed-off-by: Greg Kroah-Hartman

firmware loader: fix compile warning with PM_SLEEP set

2013-06-21T21:09:47+00:00

This patch fixes the below compile warning:

drivers/base/firmware_class.c:1254:12: warning: 'cache_firmware' defined
but not used [-Wunused-function]
 static int cache_firmware(const char *fw_name)
            ^
drivers/base/firmware_class.c:1281:12: warning: 'uncache_firmware'
defined but not used [-Wunused-function]
 static int uncache_firmware(const char *fw_name)
            ^

Reported-by: Stephen Rothwell 
Signed-off-by: Ming Lei 
Signed-off-by: Greg Kroah-Hartman

Merge branch 'driver-core-linus' into driver-core-next

2013-06-20T03:26:43+00:00

This resolves the merge issues with drivers/base/firmware_class.c

Thanks to Ming Lei for the patch and hints on how to resolve it.

Signed-off-by: Greg Kroah-Hartman

firmware loader: fix use-after-free by double abort

2013-06-18T17:41:55+00:00

fw_priv->buf is accessed in both request_firmware_load() and
writing to sysfs file of 'loading' context, but not protected
by 'fw_lock' entirely. The patch makes sure that access on
'fw_priv->buf' is protected by the lock.

So fixes the double abort problem reported by nirinA raseliarison:

	http://lkml.org/lkml/2013/6/14/188

Reported-and-tested-by: nirinA raseliarison 
Cc: Guenter Roeck 
Cc: Bjorn Helgaas 
Cc: stable  # 3.9
Signed-off-by: Ming Lei 
Signed-off-by: Greg Kroah-Hartman

firmware loader: simplify holding module for request_firmware

2013-06-06T19:41:57+00:00

module reference doesn't cover direct loading path, so this patch
simply holds the module in the whole life time of request_firmware()
to fix the problem.

Signed-off-by: Ming Lei 
Signed-off-by: Greg Kroah-Hartman

firmware loader: don't export cache_firmware and uncache_firmware

2013-06-06T19:41:57+00:00

Looks no driver has the explict requirement for the two exported
API, just don't export them anymore.

Signed-off-by: Ming Lei 
Signed-off-by: Greg Kroah-Hartman