diff options
author | Guenter Roeck <linux@roeck-us.net> | 2012-08-18 12:29:22 -0400 |
---|---|---|
committer | Mark Brown <broonie@opensource.wolfsonmicro.com> | 2012-08-22 14:26:36 -0400 |
commit | f95e1028e3317a084af955aa0b1c25a6c9213869 (patch) | |
tree | 9d5abf5261e7c8de51c183445671bdae277fab69 | |
parent | 866c0f25d2dc896e647970cf5e371b5083a6e5d5 (diff) |
spi/mpc52xx: Fix device remove function
The call sequence spi_alloc_master/spi_register_master/spi_unregister_master is
complete; it reduces the device reference count to zero, which results in
device memory being freed. An extra call to spi_master_put is unnecessary
and results in an access to free memory.
At the same time, since the call to spi_unregister_master results in device
memory being freed, it must no longer be accessed afterwards.
To fix both problems, call spi_master_get to get an extra reference to the
device, and call spi_master_put only after the last access to device data.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
-rw-r--r-- | drivers/spi/spi-mpc52xx.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/drivers/spi/spi-mpc52xx.c b/drivers/spi/spi-mpc52xx.c index a749589677be..045410650212 100644 --- a/drivers/spi/spi-mpc52xx.c +++ b/drivers/spi/spi-mpc52xx.c | |||
@@ -529,7 +529,7 @@ static int __devinit mpc52xx_spi_probe(struct platform_device *op) | |||
529 | 529 | ||
530 | static int __devexit mpc52xx_spi_remove(struct platform_device *op) | 530 | static int __devexit mpc52xx_spi_remove(struct platform_device *op) |
531 | { | 531 | { |
532 | struct spi_master *master = dev_get_drvdata(&op->dev); | 532 | struct spi_master *master = spi_master_get(dev_get_drvdata(&op->dev)); |
533 | struct mpc52xx_spi *ms = spi_master_get_devdata(master); | 533 | struct mpc52xx_spi *ms = spi_master_get_devdata(master); |
534 | int i; | 534 | int i; |
535 | 535 | ||
@@ -541,8 +541,8 @@ static int __devexit mpc52xx_spi_remove(struct platform_device *op) | |||
541 | 541 | ||
542 | kfree(ms->gpio_cs); | 542 | kfree(ms->gpio_cs); |
543 | spi_unregister_master(master); | 543 | spi_unregister_master(master); |
544 | spi_master_put(master); | ||
545 | iounmap(ms->regs); | 544 | iounmap(ms->regs); |
545 | spi_master_put(master); | ||
546 | 546 | ||
547 | return 0; | 547 | return 0; |
548 | } | 548 | } |