On Sunday, October 10, 2010, James Hogan wrote:
> Lock the pm device list mutex using device_pm_lock() and
> device_pm_unlock() around the list iteration in show_dev_hash().
>
> show_dev_hash() was reverse iterating dpm_list without first locking the
> mutex that the functions in drivers/base/power/main.c lock. I assume
> this was unintentional since there is no comment suggesting why the lock
> might not be necessary.
>
> Signed-off-by: James Hogan <james@xxxxxxxxxxxxx>
Looks good.
> ---
> drivers/base/power/trace.c | 5 ++++-
> 1 files changed, 4 insertions(+), 1 deletions(-)
>
> diff --git a/drivers/base/power/trace.c b/drivers/base/power/trace.c
> index 0a1a2c4..17e24e3 100644
> --- a/drivers/base/power/trace.c
> +++ b/drivers/base/power/trace.c
> @@ -188,8 +188,10 @@ static int show_file_hash(unsigned int value)
> static int show_dev_hash(unsigned int value)
> {
> int match = 0;
> - struct list_head *entry = dpm_list.prev;
> + struct list_head *entry;
>
> + device_pm_lock();
> + entry = dpm_list.prev;
> while (entry != &dpm_list) {
> struct device * dev = to_device(entry);
> unsigned int hash = hash_string(DEVSEED, dev_name(dev), DEVHASH);
> @@ -199,6 +201,7 @@ static int show_dev_hash(unsigned int value)
> }
> entry = entry->prev;
> }
> + device_pm_unlock();
> return match;
> }
>
>
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