I added a bit to the patch comments and committed.

On 2023/05/14 16:29, Thomas Frohwein wrote:
> I'm a bit curious if there might be a risk of other Tiger Lake-related
> issues and this could be the canary?

This is about AVX-512. AIUI it requires not just CPU support but also
OS support.  Currently we have

arch/amd64/amd64/mds.S
139:/* we don't support AVX512 yet */

If there's other software using AVX-512 which doesn't check for OS
support then that might hit it too.

The simdutf update added a check to make sure that it's working on the
OS. https://github.com/simdutf/simdutf/issues/242

It's not just Tiger Lake, there are a number of different CPU lines
which have this.

On 12th gen Alder Lake, AVX-512 is present on P cores only, some
older BIOS/microcode would allow using it if E cores are disabled,
but the feature was later disabled in newer microcode and fused
off in newer hardware, so generally not available - more at
https://www.tomshardware.com/news/intel-nukes-alder-lake-avx-512-now-fuses-it-off-in-silicon

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