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

[Marc Zyngier]

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.

        M.
--
Jazz is not dead. It just smells funny...