Allow playing dead in C3 for 5.15.y

[Public]

Hi,

A change went into 5.17 to allow CPUs to play dead in the C3 state which fixed freezes on s2idle entry if a CPU is offlined by a user. This has had some time to bake now, and a regression was identified on an ancient machine that is now fixed.

Can you please backport these commits to 5.15.y to fix that problem and avoid the regression? commit d6b88ce2eb9d2698eb24451eb92c0a1649b17bb1 ("ACPI: processor idle: Allow playing dead in C3 state") commit 0f00b1b00a44bf3b5e905dabfde2d51c490678ad ("ACPI: processor: idle: fix lockup regression on 32-bit ThinkPad T40").

Thank you!