RE: Buggy commit tracked to: "Re: [PATCH 2/9] iov_iter: move rw_copy_check_uvector() into lib/iov_iter.c"
From: David Laight <hidden>
Date: 2020-11-02 09:08:10
Also in:
io-uring, keyrings, linux-arch, linux-arm-kernel, linux-block, linux-fsdevel, linux-mips, linux-mm, linux-s390, linux-scsi, linux-security-module, linuxppc-dev, lkml, sparclinux
From: 'Greg KH'
Sent: 23 October 2020 15:47 On Fri, Oct 23, 2020 at 02:39:24PM +0000, David Laight wrote:quoted
From: David Hildenbrandquoted
Sent: 23 October 2020 15:33...quoted
I just checked against upstream code generated by clang 10 and it properly discards the upper 32bit via a mov w23 w2. So at least clang 10 indeed properly assumes we could have garbage and masks it off. Maybe the issue is somewhere else, unrelated to nr_pages ... or clang 11 behaves differently.We'll need the disassembly from a failing kernel image. It isn't that big to hand annotate.I've worked around the merge at the moment in the android tree, but it is still quite reproducable, and will try to get a .o file to disassemble on Monday or so...
Did this get properly resolved? David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)