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

From: Matthew Wilcox
Date: Wed Jun 23 2021 - 23:26:20 EST


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?