Re: Patch "MIPS: kernel: cps-vec: Replace mips32r2 ISA level with mips64r2" has been added to the 4.1-stable tree

[Paul Burton <paul.burton@imgtec.com>]

On Thu, Aug 06, 2015 at 04:30:01PM -0700, gregkh@linuxfoundation.org wrote:
> 
> This is a note to let you know that I've just added the patch titled
> 
>     MIPS: kernel: cps-vec: Replace mips32r2 ISA level with mips64r2
> 
> to the 4.1-stable tree which can be found at:
>     http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
> 
> The filename of the patch is:
>      mips-kernel-cps-vec-replace-mips32r2-isa-level-with-mips64r2.patch
> and it can be found in the queue-4.1 subdirectory.
> 
> If you, or anyone else, feels it should not be added to the stable tree,
> please let <stable@vger.kernel.org> know about it.

Hi Greg,

This patch breaks the boot of SMP kernels on Imagination's current
MIPS32 systems. This & the other MIPS64 related patches that were
submitted as part of the same series do not improve things for any CPUs
that Linux supports even as of the v4.2 cycle, so I do not believe they
should have been marked for backport.

So please either drop this patch (& preferrably the other MIPS64 CPS SMP
ones too) or also backport the series I've just submitted:

    http://marc.info/?l=linux-mips&m=143881461431570&w=2

My preference would be for not backporting any of these:

> queue-4.1/mips-kernel-cps-vec-replace-mips32r2-isa-level-with-mips64r2.patch
> queue-4.1/mips-kernel-cps-vec-use-ta0-ta3-pseudo-registers-for-64-bit.patch
> queue-4.1/revert-mips-kconfig-disable-smp-cps-for-64-bit.patch
> queue-4.1/mips-kernel-cps-vec-replace-la-macro-with-ptr_la.patch
> queue-4.1/mips-kernel-smp-cps-fix-64-bit-compatibility-errors-due-to-pointer-casting.patch
> queue-4.1/mips-kernel-cps-vec-replace-kseg0-with-ckseg0.patch
> queue-4.1/mips-cps-vec-use-macros-for-various-arithmetics-and-memory-operations.patch

Thanks,
    Paul

> 
> From 977e043d5ea1270ce985e4c165724ff91dc3c3e2 Mon Sep 17 00:00:00 2001
> From: Markos Chandras <markos.chandras@imgtec.com>
> Date: Wed, 1 Jul 2015 09:13:30 +0100
> Subject: MIPS: kernel: cps-vec: Replace mips32r2 ISA level with mips64r2
> 
> From: Markos Chandras <markos.chandras@imgtec.com>
> 
> commit 977e043d5ea1270ce985e4c165724ff91dc3c3e2 upstream.
> 
> mips32r2 is a subset of mips64r2, so we replace mips32r2 with mips64r2
> in preparation for 64-bit CPS support.
> 
> Reviewed-by: Paul Burton <paul.burton@imgtec.com>
> Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
> Cc: linux-mips@linux-mips.org
> Patchwork: https://patchwork.linux-mips.org/patch/10588/
> Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> 
> ---
>  arch/mips/kernel/cps-vec.S |    4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> --- a/arch/mips/kernel/cps-vec.S
> +++ b/arch/mips/kernel/cps-vec.S
> @@ -229,7 +229,7 @@ LEAF(mips_cps_core_init)
>  	 nop
>  
>  	.set	push
> -	.set	mips32r2
> +	.set	mips64r2
>  	.set	mt
>  
>  	/* Only allow 1 TC per VPE to execute... */
> @@ -346,7 +346,7 @@ LEAF(mips_cps_boot_vpes)
>  	 nop
>  
>  	.set	push
> -	.set	mips32r2
> +	.set	mips64r2
>  	.set	mt
>  
>  1:	/* Enter VPE configuration state */
> 
> 
> Patches currently in stable-queue which might be from markos.chandras@imgtec.com are
> 
> queue-4.1/mips-kernel-cps-vec-replace-mips32r2-isa-level-with-mips64r2.patch
> queue-4.1/mips-kernel-cps-vec-use-ta0-ta3-pseudo-registers-for-64-bit.patch
> queue-4.1/revert-mips-kconfig-disable-smp-cps-for-64-bit.patch
> queue-4.1/mips-require-o32-fp64-support-for-mips64-with-o32-compat.patch
> queue-4.1/mips-fpu.h-allow-64-bit-fpu-on-a-64-bit-mips-r6-cpu.patch
> queue-4.1/mips-kernel-cps-vec-replace-la-macro-with-ptr_la.patch
> queue-4.1/mips-c-r4k-fix-cache-flushing-for-mt-cores.patch
> queue-4.1/mips-kernel-smp-cps-fix-64-bit-compatibility-errors-due-to-pointer-casting.patch
> queue-4.1/mips-kernel-cps-vec-replace-kseg0-with-ckseg0.patch
> queue-4.1/mips-fix-erroneous-jr-emulation-for-mips-r6.patch
> queue-4.1/mips-cps-vec-use-macros-for-various-arithmetics-and-memory-operations.patch