Re: [kbuild] fs/fuse/dax.c:113 fuse_setup_one_mapping() warn: should 'start_idx << 21' be a 64 bit type?

[Miklos Szeredi]

On Mon, May 3, 2021 at 3:27 PM Dan Carpenter <dan.carpenter@xxxxxxxxxx> wrote:
>
> tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git  master
> head:   9ccce092fc64d19504fa54de4fd659e279cc92e7
> commit: c2d0ad00d948de73c78f05d2b3e5bdfa605035cc virtiofs: implement dax read/write operations
> config: i386-randconfig-m031-20210503 (attached as .config)
> compiler: gcc-9 (Debian 9.3.0-22) 9.3.0
>
> If you fix the issue, kindly add following tag as appropriate
> Reported-by: kernel test robot <lkp@xxxxxxxxx>
> Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
>
> New smatch warnings:
> fs/fuse/dax.c:113 fuse_setup_one_mapping() warn: should 'start_idx << 21' be a 64 bit type?

Yes.

But does it make any sense to enable virtiofs and/or dax on 32bit
guest? We sure aren't testing it, as seen from this bug report.

Vivek, what do you think?

Thanks,
Miklos