Re: [PATCH] of: Fix locking when calling of_get_next_available_child()

[Grant Likely]

On Mon, Feb 11, 2013 at 10:27 PM, Rob Herring <robherring2@xxxxxxxxx> wrote:
> On 02/11/2013 04:19 PM, Grant Likely wrote:
>> of_get_next_available_child() obtains the devtree_lock and then calls
>> of_device_is_available() which also attempts to claim the lock. This is
>> obviously incorrect and causes a deadlock on boot. Fix issue by adding
>> an variant of of_device_is_available() which doesn't obtain the lock.
>>
>> Cc: Stephen Warren <swarren@xxxxxxxxxxxxx>
>> Cc: Rob Herring <robherring2@xxxxxxxxx>
>> Signed-off-by: Grant Likely <grant.likely@xxxxxxxxxxxx>
>> ---
>>  drivers/of/base.c |   15 +++++++++++++--
>>  1 file changed, 13 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/of/base.c b/drivers/of/base.c
>> index e8d65af..4af74b7 100644
>> --- a/drivers/of/base.c
>> +++ b/drivers/of/base.c
>> @@ -297,7 +297,7 @@ EXPORT_SYMBOL(of_machine_is_compatible);
>>   *  Returns 1 if the status property is absent or set to "okay" or "ok",
>>   *  0 otherwise
>>   */
>> -int of_device_is_available(const struct device_node *device)
>> +int __of_device_is_available(const struct device_node *device)
>>  {
>>       const char *status;
>>       int statlen;
>> @@ -313,6 +313,17 @@ int of_device_is_available(const struct device_node *device)
>>
>>       return 0;
>>  }
>> +
>> +int of_device_is_available(const struct device_node *device)
>
> Stephen's version wins because he preserved the documentation. :)

Pish. He just cut and paste the documentation so now we have 2 copies.
My version wins because it is already in my tree. So ptfff!

:-)

g.
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