Re: [linus:master] [x86/entry] be5341eb0d: WARNING:CPU:#PID:#at_int80_emulation

From: Linus Torvalds
Date: Thu Dec 21 2023 - 00:39:23 EST


On Wed, 20 Dec 2023 at 15:40, Sami Tolvanen <samitolvanen@xxxxxxxxxx> wrote:
>
> I tested the patch with the 0-day bot reproducer and it does fix the
> warning. My usual arm64 and riscv configs also seem to build and boot
> just fine.

Thanks. I've been running it on my machine too, and still don't see
anything wrong with it..

I suspect all sane people are already on xmas break, which explains
why people are being quiet. They _should_ be.

But since I'm not in that sane group, I decided to just bypass the
normal channels and apply it directly.

It really isn't all that critical, since I don't expect anybody to
actually disable the posix timer subsystem: I think the config
variable came out of the kernel minimization project, and it's
probably much more likely that people turn off CFI (particularly since
you afaik still need to build with clang to get it) than that they'd
turn off the posix timer support.

But I think it's a worthy cleanup of some messy system call macros, so
I wanted to put this behind us whether it truly matters or not.

Linus