[PATCH] powerpc/idle: Don't corrupt back chain when going idle

[Michael Ellerman]

On Wed, 20 Oct 2021 20:48:26 +1100, Michael Ellerman wrote:
> In isa206_idle_insn_mayloss() we store various registers into the stack
> red zone, which is allowed.
> 
> However inside the IDLE_STATE_ENTER_SEQ_NORET macro we save r2 again,
> to 0(r1), which corrupts the stack back chain.
> 
> We used to do the same in isa206_idle_insn_mayloss() itself, but we
> fixed that in 73287caa9210 ("powerpc64/idle: Fix SP offsets when saving
> GPRs"), however we missed that the macro also corrupts the back chain.
> 
> [...]

Applied to powerpc/fixes.

[1/1] powerpc/idle: Don't corrupt back chain when going idle
      https://git.kernel.org/powerpc/c/496c5fe25c377ddb7815c4ce8ecfb676f051e9b6

cheers