Re: [PATCH 0/3] arm64:msr: Add MSR driver

[Rongwei Wang]

> On Dec 3, 2020, at 7:45 PM, Marc Zyngier <maz@xxxxxxxxxx> wrote:
> 
> On 2020-12-03 11:25, Rongwei Wang wrote:
>>> 2020年12月3日 下午4:35，Marc Zyngier <maz@xxxxxxxxxx> 写道：
> 
> [...]
> 
>>> But what does it mean to change random system registers while the kernel
>>> itself is using them in parallel? All you are introducing is a bunch of
>>> uncontrolled, unexpected, and possibly fatal side effects.
>> This problem exists when writing to a register, but it does not exist
>> when reading a register.
> 
> If you're not aware that the ARM architecture does have system registers
> with read side-effects, you really shouldn't be writing this code.
Thanks, Does it make sense to put this feature in the drivers/ directory, likes misc drivers? Whether it can exist as a debugging tool in kernel or not?
When debugging, then enables CONFIG_ARM64_MSR or CONFIG_ARM64_MSR_DEBUG.
> 
>        M.
> -- 
> Jazz is not dead. It just smells funny…
Thanks,
Rongwei Wang.