Re: [PATCH] misc: sgi-xp: Properly initialize buf in xpc_get_rsvd_page_pa
From: Stephen Hines
Date: Thu May 23 2019 - 12:49:46 EST
Looks good to me. :) Since I don't contribute to the Linux kernel
directly, I appreciate you picking this up.
Thanks,
Steve
On Thu, May 23, 2019 at 9:20 AM Nathan Chancellor
<natechancellor@xxxxxxxxx> wrote:
>
> Clang warns:
>
> drivers/misc/sgi-xp/xpc_partition.c:73:14: warning: variable 'buf' is
> uninitialized when used within its own initialization [-Wuninitialized]
> void *buf = buf;
> ~~~ ^~~
> 1 warning generated.
>
> Initialize it to NULL, which is more deterministic.
>
> Fixes: 279290294662 ("[IA64-SGI] cleanup the way XPC locates the reserved page")
> Link: https://github.com/ClangBuiltLinux/linux/issues/466
> Suggested-by: Stephen Hines <srhines@xxxxxxxxxx>
> Signed-off-by: Nathan Chancellor <natechancellor@xxxxxxxxx>
> ---
>
> Thanks Steve for the suggestion, don't know why that never crossed my
> mind...
>
> I tried to follow buf all the way down in get_partition_rsvd_page to see
> if there would be any dereferences and I didn't see any but I could
> have easily missed something.
>
> drivers/misc/sgi-xp/xpc_partition.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/misc/sgi-xp/xpc_partition.c b/drivers/misc/sgi-xp/xpc_partition.c
> index 3eba1c420cc0..782ce95d3f17 100644
> --- a/drivers/misc/sgi-xp/xpc_partition.c
> +++ b/drivers/misc/sgi-xp/xpc_partition.c
> @@ -70,7 +70,7 @@ xpc_get_rsvd_page_pa(int nasid)
> unsigned long rp_pa = nasid; /* seed with nasid */
> size_t len = 0;
> size_t buf_len = 0;
> - void *buf = buf;
> + void *buf = NULL;
> void *buf_base = NULL;
> enum xp_retval (*get_partition_rsvd_page_pa)
> (void *, u64 *, unsigned long *, size_t *) =
> --
> 2.22.0.rc1
>