On Dec 3, 2020, at 7:45 PM, Marc Zyngier [off-list ref] wrote:

On 2020-12-03 11:25, Rongwei Wang wrote:

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2020年12月3日 下午4:35，Marc Zyngier [off-list ref] 写道：

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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.


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