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Subject: Re: [PATCH 0/3] arm64:msr: Add MSR driver
From:   wangrongwei <rongwei.wang@linux.alibaba.com>
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 <5e7f7225982b2df63e62ea60ec632376@misterjones.org>
To:     Marc Zyngier <maz@kernel.org>
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Hi
We have validate this driver in vm and physical machine, and works fine.
Actually, we used existing interfaces to realize this driver, likes aarch64_insn_read and aarch64_insn_patch_text. These existing intefaces had validated a CPU. 

> 2020年12月1日 上午2:05，Marc Zyngier <maz@kernel.org> 写道：
> 
> On 2020-11-30 17:48, Rongwei Wang wrote:
> 
>> The interfaces of this module is same as MSR module in user space, and to solve
>> the problem that ARM platform has no similar MSR module. Using this interface,
>> we did some pressure tests to test the stability and security of MSR driver. The
>> test results show that the driver will not cause system panic if various
>> illegal values and multithreading concurrent access are passed through the
>> interface.
> 
> It would certainly help if you described what problem you are trying
> to solve here. In general, giving userspace access to random system
> registers is a pretty bad idea.
> 
> Are you trying to validate a CPU? a hypervisor? Or is it just a fun way
> to check how many things you can poke before something catches fire?
> 
> Thanks,
> 
>        M.
> -- 
> Jazz is not dead. It just smells funny...