Messages in this thread | | | From | Arnd Bergmann <> | Subject | Re: arm64: kernel v4.6-rc1 hangs on QEMU | Date | Wed, 30 Mar 2016 00:32:42 +0200 |
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On Wednesday 30 March 2016 01:22:17 Yury Norov wrote: > > > > Undefined instruction in cpuinfo_store_boot_cpu() could be related > > to the SYS_ID_AA64MMFR2_EL1 access that was recently added. > > > > What does the architecture say about reading unknown cpuid registers? > > > > Arnd > > ThunderX has some unimplemented system registers. AFAIR, attempt to access it > causes data abort.
Ok, if that is the case, maybe the read_cpuid() macro can be changed so it contains a fixup for the trap? That should handle both data abort and undefinstr.
Arnd
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