[BUG] arm64: an infinite loop in generic_perform_write()

[Matthew Wilcox]

On Thu, Jun 24, 2021 at 11:10:41AM +0800, Chen Huang wrote:
> In userspace, I perform such operation:
> 
>  	fd = open("/tmp/test", O_RDWR | O_SYNC);
>         access_address = (char *)mmap(NULL, uio_size, PROT_READ, MAP_SHARED, uio_fd, 0);
>         ret = write(fd, access_address + 2, sizeof(long));

... you know that accessing this at unaligned offsets isn't going to
work.  It's completely meaningless.  Why are you trying to do it?