Re: [PATCH v2 21/21] arm64: Panic when VHE and non VHE CPUs coexist
From: Marc Zyngier
Date: Tue Jan 26 2016 - 09:34:44 EST
On 26/01/16 14:25, Suzuki K. Poulose wrote:
> On 25/01/16 15:53, Marc Zyngier wrote:
>> Having both VHE and non-VHE capable CPUs in the same system
>> is likely to be a recipe for disaster.
>> diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c
>> index b1adc51..bc7650a 100644
>> --- a/arch/arm64/kernel/smp.c
>> +++ b/arch/arm64/kernel/smp.c
>> @@ -113,6 +113,9 @@ int __cpu_up(unsigned int cpu, struct task_struct *idle)
>> pr_crit("CPU%u: failed to come online\n", cpu);
>> ret = -EIO;
>> + if (is_kernel_mode_mismatched())
>> + panic("CPU%u: incompatible execution level", cpu);
> I have a series which tries to perform some checks for early CPU features,
> like this at  and adds support for early CPU boot failures, passing the error
> status back to the master. May be we could move this check there(once it settles),
> and fail the CPU boot with CPU_PANIC_KERNEL status.
>  http://lists.infradead.org/pipermail/linux-arm-kernel/2016-January/401727.html
Definitely, there is room for consolidation in this area...
Jazz is not dead. It just smells funny...