Re: [PATCH 00/14] powerpc/rtas: various cleanups and improvements

[Laurent Dufour <ldufour@linux.ibm.com>]

Hi Nick,

As this series needs additional work, I just sent a single patch [1] fixing
the MSR[RI] issue addressed in the patch 9/14 of this series.

I did that because that fix is fixing a panic currently seen and this will
ease backport to stable and distro kernel.

I suggest rebasing this series on top of this new patch.

Cheers,
Laurent.

1:
https://lore.kernel.org/linuxppc-dev/20220317110601.86917-1-ldufour@linux.ibm.com/

On 08/03/2022, 14:50:33, Nicholas Piggin wrote:
> I had a bunch of random little fixes and cleanups around and
> was prompted to put them together and make a change to call
> RTAS with MSR[RI] enabled because of a report of the hard
> lockup watchdog NMI IPI hitting in an rtas call which then
> crashed because it's unrecoverable.
> 
> Could possibly move patch 9 earlier if it would help with
> backporting.
> 
> Thanks,
> Nick
> 
> Nicholas Piggin (14):
>   powerpc/rtas: Move rtas entry assembly into its own file
>   powerpc/rtas: Make enter_rtas a nokprobe symbol on 64-bit
>   powerpc/rtas: Fix whitespace in rtas_entry.S
>   powerpc/rtas: Call enter_rtas with MSR[EE] disabled
>   powerpc/rtas: Modernise RI clearing on 64-bit
>   powerpc/rtas: Load rtas entry MSR explicitly
>   powerpc/rtas: PACA can be restored directly from SPRG
>   powerpc/rtas: call enter_rtas in real-mode on 64-bit
>   powerpc/rtas: Leave MSR[RI] enabled over RTAS call
>   powerpc/rtas: replace rtas_call_unlocked with raw_rtas_call
>   powerpc/rtas: tidy __fetch_rtas_last_error
>   powerpc/rtas: Close theoretical memory leak
>   powerpc/rtas: enture rtas_call is called with MMU enabled
>   powerpc/rtas: Consolidate and improve checking for rtas callers
> 
>  arch/powerpc/include/asm/rtas.h              |   4 +-
>  arch/powerpc/kernel/Makefile                 |   2 +-
>  arch/powerpc/kernel/entry_32.S               |  49 ------
>  arch/powerpc/kernel/entry_64.S               | 150 -------------------
>  arch/powerpc/kernel/rtas.c                   | 132 +++++++++-------
>  arch/powerpc/kernel/rtas_entry.S             | 144 ++++++++++++++++++
>  arch/powerpc/platforms/pseries/hotplug-cpu.c |   2 +-
>  arch/powerpc/platforms/pseries/ras.c         |   7 +-
>  arch/powerpc/xmon/xmon.c                     |   2 +-
>  9 files changed, 227 insertions(+), 265 deletions(-)
>  create mode 100644 arch/powerpc/kernel/rtas_entry.S
>