Re: port-amd64/54962 (cannot boot NetBSD-current on VMware player 15 on Ryzen 5 3600X after sys/arch/x86/x86/cpu_topology.c:r1.18)

[Kengo NAKAHARA <k-nakahara%iij.ad.jp@localhost>]

Hi,

Thank you for your comment.

On 2020/02/16 3:01, maxv%NetBSD.org@localhost wrote:
> Synopsis: cannot boot NetBSD-current on VMware player 15 on Ryzen 5 3600X after sys/arch/x86/x86/cpu_topology.c:r1.18
>
> State-Changed-From-To: open->feedback
> State-Changed-By: maxv%NetBSD.org@localhost
> State-Changed-When: Sat, 15 Feb 2020 18:01:49 +0000
> State-Changed-Why:
> I noticed a bug in x86_cpu_topology() some time ago:
>
> 115 		/* Maximum number of LPs sharing a cache (ebx[23:16]). */
> 116 		x86_cpuid(1, descs);
> 117 		lp_max = __SHIFTOUT(descs[1], CPUID_HTT_CORES);
>
> The Intel specification (SDM Volume 1) says:
>
> 	"The nearest power-of-2 integer that is not smaller than EBX[23:16] is the
> 	 number of unique initial APICIDs reserved for addressing different logical
> 	 processors in a physical package"
>
> So here lp_max should be rounded up to the nearest power-of-2.

I try the fix, however the kernel cannot boot on my environment.
Hmm, it may have other bug(s)...


Thanks,

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Kengo NAKAHARA <k-nakahara%iij.ad.jp@localhost>