diff options
| author | Josh Wu <josh.wu@atmel.com> | 2013-11-05 17:59:07 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-12-04 11:05:25 -0800 |
| commit | 8a631f3a6a650c3445b4463913e9aca50aafdde6 (patch) | |
| tree | 3c2fd385f49351ef17e06e780487a58d30324470 /drivers/mtd | |
| parent | 7524987e3c505dd4e96c1eae5001e06c91d481e9 (diff) | |
mtd: atmel_nand: fix bug driver will in a dead lock if no nand detected
commit a749d13acd8e079ed4c77a9456d842dc94af8f17 upstream.
In the atmel driver probe function, the code shows like following:
atmel_nand_probe(...) {
...
err_nand_ioremap:
platform_driver_unregister(&atmel_nand_nfc_driver);
return res;
}
If no nand flash detected, the driver probe function will goto
err_nand_ioremap label.
Then platform_driver_unregister() will be called. It will get the
lock of atmel_nand device since it is parent of nfc_device. The
problem is the lock is already hold by atmel_nand_probe itself.
So system will be in a dead lock.
This patch just simply removed to platform_driver_unregister() call.
When atmel_nand driver is quit the platform_driver_unregister() will
be called in atmel_nand_remove().
[Brian: the NAND platform probe really has no business
registering/unregistering another driver; this fixes the deadlock, but
we should follow up the likely racy behavior here with a better
architecture]
Signed-off-by: Josh Wu <josh.wu@atmel.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/mtd')
| -rw-r--r-- | drivers/mtd/nand/atmel_nand.c | 1 |
1 files changed, 0 insertions, 1 deletions
diff --git a/drivers/mtd/nand/atmel_nand.c b/drivers/mtd/nand/atmel_nand.c index 060feeaf6b3e..9be079224761 100644 --- a/drivers/mtd/nand/atmel_nand.c +++ b/drivers/mtd/nand/atmel_nand.c @@ -2177,7 +2177,6 @@ err_no_card: if (host->dma_chan) dma_release_channel(host->dma_chan); err_nand_ioremap: - platform_driver_unregister(&atmel_nand_nfc_driver); return res; } |