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: 2020-10-23 14:39:37
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: David Hildenbrand
Sent: 23 October 2020 15:33
...
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. David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)