Re: [PATCH v7 5/9] powerpc/pseries: flush SLB contents on SLB MCE errors.

[Nicholas Piggin <npiggin@gmail.com>]

On Tue, 07 Aug 2018 19:47:14 +0530
Mahesh J Salgaonkar <mahesh@linux.vnet.ibm.com> wrote:

> From: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
> 
> On pseries, as of today system crashes if we get a machine check
> exceptions due to SLB errors. These are soft errors and can be fixed by
> flushing the SLBs so the kernel can continue to function instead of
> system crash. We do this in real mode before turning on MMU. Otherwise
> we would run into nested machine checks. This patch now fetches the
> rtas error log in real mode and flushes the SLBs on SLB errors.
> 
> Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
> Signed-off-by: Michal Suchanek <msuchanek@suse.com>
> ---
> 
> Changes in V7:
> - Fold Michal's patch into this patch.
> - Handle MSR_RI=0 and evil context case in MC handler.
> ---


> diff --git a/arch/powerpc/mm/slb.c b/arch/powerpc/mm/slb.c
> index cb796724a6fc..e89f675f1b5e 100644
> --- a/arch/powerpc/mm/slb.c
> +++ b/arch/powerpc/mm/slb.c
> @@ -145,6 +145,12 @@ void slb_flush_and_rebolt(void)
>  	get_paca()->slb_cache_ptr = 0;
>  }
>  
> +void slb_flush_and_rebolt_realmode(void)
> +{
> +	__slb_flush_and_rebolt();
> +	get_paca()->slb_cache_ptr = 0;
> +}
> +
>  void slb_vmalloc_update(void)
>  {
>  	unsigned long vflags;

Can you use this patch for the SLB flush?

https://patchwork.ozlabs.org/patch/953034/

Thanks,
Nick