Re: [PATCH v2] prctl: PR_SET_MM - unify copying of user's auvx

[Cyrill Gorcunov]

On Wed, Sep 29, 2021 at 11:20:23PM +0800, kernel test robot wrote:
...
> sparse warnings: (new ones prefixed by >>)
> >> kernel/sys.c:1997:58: sparse: sparse: incorrect type in argument 3 (different address spaces) @@     expected void const [noderef] __user *addr @@     got unsigned long long [usertype] *[addressable] auxv @@
>    kernel/sys.c:1997:58: sparse:     expected void const [noderef] __user *addr
>    kernel/sys.c:1997:58: sparse:     got unsigned long long [usertype] *[addressable] auxv
>    kernel/sys.c:1068:32: sparse: sparse: incorrect type in argument 1 (different address spaces) @@     expected struct task_struct *p1 @@     got struct task_struct [noderef] __rcu *real_parent @@
>    kernel/sys.c:1068:32: sparse:     expected struct task_struct *p1
>    kernel/sys.c:1068:32: sparse:     got struct task_struct [noderef] __rcu *real_parent
>    kernel/sys.c: note: in included file (through include/linux/rcuwait.h, include/linux/percpu-rwsem.h, include/linux/fs.h, ...):
>    include/linux/sched/signal.h:710:37: sparse: sparse: incorrect type in argument 1 (different address spaces) @@     expected struct spinlock [usertype] *lock @@     got struct spinlock [noderef] __rcu * @@
>    include/linux/sched/signal.h:710:37: sparse:     expected struct spinlock [usertype] *lock
>    include/linux/sched/signal.h:710:37: sparse:     got struct spinlock [noderef] __rcu *
> 
> vim +1997 kernel/sys.c

Thanks for report! I happen to miss Dima's reply in first place as well :(
I'll take a look on this patch. The issie itself is implicit type conversion,
shouldn't be a bug in general but need to address as well. Will do.