Re: [RFC PATCH 2/6] powerpc/64s: Helpers to switch between linear and vmapped stack pointers

2022-11-07 Thread Nicholas Piggin
On Sat Nov 5, 2022 at 6:00 PM AEST, Christophe Leroy wrote: > > > Le 04/11/2022 à 18:27, Andrew Donnellan a écrit : > > powerpc unfortunately has too many places where we run stuff in real mode. > > > > With CONFIG_VMAP_STACK enabled, this means we need to be able to swap the > > stack pointer to

Re: [RFC PATCH 2/6] powerpc/64s: Helpers to switch between linear and vmapped stack pointers

2022-11-05 Thread Christophe Leroy
Le 05/11/2022 à 09:00, Christophe Leroy a écrit : Le 04/11/2022 à 18:27, Andrew Donnellan a écrit : powerpc unfortunately has too many places where we run stuff in real mode. With CONFIG_VMAP_STACK enabled, this means we need to be able to swap the stack pointer to use the linear mapping w

Re: [RFC PATCH 2/6] powerpc/64s: Helpers to switch between linear and vmapped stack pointers

2022-11-05 Thread Christophe Leroy
Le 04/11/2022 à 18:27, Andrew Donnellan a écrit : > powerpc unfortunately has too many places where we run stuff in real mode. > > With CONFIG_VMAP_STACK enabled, this means we need to be able to swap the > stack pointer to use the linear mapping when we enter a real mode section, > and back aft

[RFC PATCH 2/6] powerpc/64s: Helpers to switch between linear and vmapped stack pointers

2022-11-04 Thread Andrew Donnellan
powerpc unfortunately has too many places where we run stuff in real mode. With CONFIG_VMAP_STACK enabled, this means we need to be able to swap the stack pointer to use the linear mapping when we enter a real mode section, and back afterwards. Store the top bits of the stack pointer in both the