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Re: dtracing unlink



On Mon, Oct 30, 2023 at 11:33:24AM +0000, RVP wrote:
> The NetBSD copyinstr() _disables_ SMAP before copying data from
> userspace.  The dtrace version _does not_. I think this is what
> fails on some CPUs. My Intel CPU's more than 10 years old so it
> doesn't support SMAP (only SMEP), dtrace works for me. If you and
> bch tell me that your CPUs support SMAP, then that would be the
> smoking gun.

# cpuctl identify 0 | grep SMAP
cpu0: features5 0xf1bf97a9<AVX512F,AVX512DQ,RDSEED,ADX,SMAP,AVX512_IFMA>

Looks that way!
 Thomas


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