[PATCH 3/4][v2] fsl_rio: move machine_check handler into machine_check_e500 & machine_check_e500mc

[Xie Shaohui-B21989]

Best Regards, 
Shaohui Xie 


> -----Original Message-----
> From: Bounine, Alexandre [mailto:Alexandre.Bounine at idt.com]
> Sent: Thursday, November 11, 2010 6:55 AM
> To: Xie Shaohui-B21989; akpm at linux-foundation.org
> Cc: linux-kernel at vger.kernel.org; linuxppc-dev at lists.ozlabs.org; Li
Yang-
> R58472; Gala Kumar-B11780; Zang Roy-R61911
> Subject: RE: [PATCH 3/4][v2] fsl_rio: move machine_check handler into
> machine_check_e500 & machine_check_e500mc
> 
> Shaohui Xie <b21989 at freescale.com> wrote:
> >
> > diff --git a/arch/powerpc/kernel/traps.c
b/arch/powerpc/kernel/traps.c
> > index a45a63c..2a5fb9d 100644
> > --- a/arch/powerpc/kernel/traps.c
> > +++ b/arch/powerpc/kernel/traps.c
> > @@ -55,6 +55,7 @@
> >  #endif
> >  #include <asm/kexec.h>
> >  #include <asm/ppc-opcode.h>
> > +#include <linux/rio.h>
> >
> >  #if defined(CONFIG_DEBUGGER) || defined(CONFIG_KEXEC)  int
> > (*__debugger)(struct pt_regs *regs) __read_mostly; @@ -500,6 +501,13
> > @@ int machine_check_e500mc(struct pt_regs *regs)
> >  		       reason & MCSR_MEA ? "Effective" : "Physical",
> addr);
> >  	}
> >
> > +	if (reason & MCSR_BUS_RBERR) {
> > +		printk("Bus - Read Data Bus Error\n"); #ifdef
CONFIG_RAPIDIO
> > +		recoverable = fsl_rio_mcheck_exception(regs); #endif
> > +	}
> > +
> >  	mtspr(SPRN_MCSR, mcsr);
> >  	return mfspr(SPRN_MCSR) == 0 && recoverable;  } @@ -527,8
+535,12
> @@
> > int machine_check_e500(struct pt_regs *regs)
> >  		printk("Bus - Write Address Error\n");
> >  	if (reason & MCSR_BUS_IBERR)
> >  		printk("Bus - Instruction Data Error\n");
> > -	if (reason & MCSR_BUS_RBERR)
> > +	if (reason & MCSR_BUS_RBERR) {
> >  		printk("Bus - Read Data Bus Error\n");
> > +#ifdef CONFIG_RAPIDIO
> > +		fsl_rio_mcheck_exception(regs);
> > +#endif
> > +	}
> >  	if (reason & MCSR_BUS_WBERR)
> >  		printk("Bus - Read Data Bus Error\n");
> >  	if (reason & MCSR_BUS_IPERR)
> 
> This implementation breaks an intended use of
> fsl_rio_mcheck_exception():
> 1. for e500 it does not check the return value of the rio handler and
> crashes the system even after RIO Mchk was serviced. Looks like e500mc
> version handles it better but I have no HW to test it.
> 2. the RIO Mchk is expected to be handled quietly but here it has many
> printk's. May be it is better to call the fsl_rio_mcheck_exception()
> handler in very beginning and simply exit if it returns 1.
> 
> Alex.
[Xie Shaohui-B21989] Hi Alex, seems your suggestion is some kind of
conflict with Kumar, you can have a look at 
http://patchwork.ozlabs.org/patch/67774/

Thanks
Shaohui

> 
>