Re: [PATCH 1/3] remoteproc: fix a bug in rproc_alloc()

[Alex Elder <elder@linaro.org>]

On 4/8/20 5:16 PM, Mathieu Poirier wrote:
> Hi Alex,
> 
> On Fri, 3 Apr 2020 at 11:50, Alex Elder <elder@linaro.org> wrote:
>>
>> If ida_simple_get() returns an error when called in rproc_alloc(),
>> put_device() is called to clean things up.  By this time the rproc
>> device type has been assigned, with rproc_type_release() as the
>> release function.
>>
>> The first thing rproc_type_release() does is call:
>>     idr_destroy(&rproc->notifyids);
>>
>> But at the time the ida_simple_get() call is made, the notifyids
>> field in the remoteproc structure has not been initialized.
>>
>> I'm not actually sure this case causes an observable problem, but
>> it's incorrect.  Fix this by initializing the notifyids field before
>> calling ida_simple_get() in rproc_alloc().
>>
> 
> Both Suman and I are meddling in function rproc_alloc() for our
> respective work [1][2].  I will add this patch to a set that refactors
> rproc_alloc() as soon as v5.7-rc1 comes out.  That way we can all base
> our work on the same foundation and Bjorn doesn't have to fix 3
> different merge conflicts.
> 
> Thanks,
> Mathieu

Fine with me.  Thanks a lot.	-Alex

> [1]. https://patchwork.kernel.org/patch/11456385/
> [2]. https://patchwork.kernel.org/project/linux-remoteproc/list/?series=261069
> 
>> Signed-off-by: Alex Elder <elder@linaro.org>
>> ---
>>  drivers/remoteproc/remoteproc_core.c | 4 ++--
>>  1 file changed, 2 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c
>> index e12a54e67588..59b6eb22f01c 100644
>> --- a/drivers/remoteproc/remoteproc_core.c
>> +++ b/drivers/remoteproc/remoteproc_core.c
>> @@ -2054,6 +2054,8 @@ struct rproc *rproc_alloc(struct device *dev, const char *name,
>>         rproc->dev.class = &rproc_class;
>>         rproc->dev.driver_data = rproc;
>>
>> +       idr_init(&rproc->notifyids);
>> +
>>         /* Assign a unique device index and name */
>>         rproc->index = ida_simple_get(&rproc_dev_index, 0, 0, GFP_KERNEL);
>>         if (rproc->index < 0) {
>> @@ -2078,8 +2080,6 @@ struct rproc *rproc_alloc(struct device *dev, const char *name,
>>
>>         mutex_init(&rproc->lock);
>>
>> -       idr_init(&rproc->notifyids);
>> -
>>         INIT_LIST_HEAD(&rproc->carveouts);
>>         INIT_LIST_HEAD(&rproc->mappings);
>>         INIT_LIST_HEAD(&rproc->traces);
>> --
>> 2.20.1
>>