diff options
| author | Josh Wu <josh.wu@atmel.com> | 2013-11-05 13:59:07 +0400 |
|---|---|---|
| committer | Brian Norris <computersforpeace@gmail.com> | 2013-11-07 22:16:21 +0400 |
| commit | a749d13acd8e079ed4c77a9456d842dc94af8f17 (patch) | |
| tree | a985aec3449dfb56af521cf13237aebf617335a7 | |
| parent | 97de79e02d5e85b4a147b74cc2947b8613d806f7 (diff) | |
| download | linux-a749d13acd8e079ed4c77a9456d842dc94af8f17.tar.xz | |
mtd: atmel_nand: fix bug driver will in a dead lock if no nand detected
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>
Cc: <stable@vger.kernel.org> # 3.12
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
| -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 ef9c9f547c01..469d4e2c450a 100644 --- a/drivers/mtd/nand/atmel_nand.c +++ b/drivers/mtd/nand/atmel_nand.c @@ -2142,7 +2142,6 @@ 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; } |