Hi Bjorn,
On 3/26/20 12:42 AM, Bjorn Andersson wrote:
> On Tue 24 Mar 13:18 PDT 2020, Suman Anna wrote:
>
>> The current name field used in the remoteproc structure is simply
>> a pointer to a name field supplied during the rproc_alloc() call.
>> The pointer passed in by remoteproc drivers during registration is
>> typically a dev_name pointer, but it is possible that the pointer
>> will no longer remain valid if the devices themselves were created
>> at runtime like in the case of of_platform_populate(), and were
>> deleted upon any failures within the respective remoteproc driver
>> probe function.
>>
>> So, allocate and maintain a local copy for this name field to
>> keep it agnostic of the logic used in the remoteproc drivers.
>>
>> Signed-off-by: Suman Anna <s-anna@xxxxxx>
>> ---
>> drivers/remoteproc/remoteproc_core.c | 9 ++++++++-
>> include/linux/remoteproc.h | 2 +-
>> 2 files changed, 9 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c
>> index aca6d022901a..6e0b91fa6f11 100644
>> --- a/drivers/remoteproc/remoteproc_core.c
>> +++ b/drivers/remoteproc/remoteproc_core.c
>> @@ -1989,6 +1989,7 @@ static void rproc_type_release(struct device *dev)
>>
>> kfree(rproc->firmware);
>> kfree(rproc->ops);
>> + kfree(rproc->name);
>> kfree(rproc);
>> }
>>
>> @@ -2061,7 +2062,13 @@ struct rproc *rproc_alloc(struct device *dev, const char *name,
>> }
>>
>> rproc->firmware = p;
>> - rproc->name = name;
>> + rproc->name = kstrdup(name, GFP_KERNEL);
>
> Let's use kstrdup_const() instead here (and kfree_const() instead of
> kfree()), so that the cases where we are passed a constant we won't
> create a duplicate on the heap.
>
> And the "name" in struct rproc can remain const.
Agreed, that's better functions to use for this.
>
>> + if (!rproc->name) {
>> + kfree(p);
>> + kfree(rproc->ops);
>> + kfree(rproc);
>> + return NULL;
>
> Perhaps we can rearrange the hunks here slightly and get to a point
> where we can rely on the release function earlier?
Not sure I understand. I don't see any release function, all failure
paths in rproc_alloc() directly unwind the previous operations. You mean
move this to before the alloc for rproc structure, something similar to
what we are doing with firmware?
regards
Suman
>
> Regards,
> Bjorn
>
>> + }
>> rproc->priv = &rproc[1];
>> rproc->auto_boot = true;
>> rproc->elf_class = ELFCLASS32;
>> diff --git a/include/linux/remoteproc.h b/include/linux/remoteproc.h
>> index ddce7a7775d1..77788a4bb94e 100644
>> --- a/include/linux/remoteproc.h
>> +++ b/include/linux/remoteproc.h
>> @@ -490,7 +490,7 @@ struct rproc_dump_segment {
>> struct rproc {
>> struct list_head node;
>> struct iommu_domain *domain;
>> - const char *name;
>> + char *name;
>> char *firmware;
>> void *priv;
>> struct rproc_ops *ops;
>> --
>> 2.23.0
>>
