[PATCH v4] Make instruction dumping work in real mode.

[PATCH v4] Make instruction dumping work in real mode.

[Scott Wood]

On non-book-E-or-4xx, exceptions execute in real mode.  If a fault happens
that leads to a register dump, the kernel currently prints XXXXXXXX because
it doesn't realize that PC is a physical address.

This patch checks the state of the IMMU, and if necessary converts PC into a
virtual address.

Signed-off-by: Scott Wood <scottwood@freescale.com>
---
OK, just CONFIG_BOOKE this time. :-P

 arch/powerpc/kernel/process.c |    8 ++++++++
 1 files changed, 8 insertions(+), 0 deletions(-)

diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index 57c589c..6dbde7f 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -354,6 +354,14 @@ static void show_instructions(struct pt_regs *regs)
 		if (!(i % 8))
 			printk("\n");
 
+#if !defined(CONFIG_BOOKE)
+		/* If executing with the IMMU off, adjust pc rather
+		 * than print XXXXXXXX.
+		 */
+		if (!(regs->msr & MSR_IR))
+			pc = (unsigned long)phys_to_virt(pc);
+#endif
+
 		/* We use __get_user here *only* to avoid an OOPS on a
 		 * bad address because the pc *should* only be a
 		 * kernel address.
-- 
1.5.3.1

Re: [PATCH v4] Make instruction dumping work in real mode.

[Kumar Gala]

On Sep 27, 2007, at 1:38 PM, Scott Wood wrote:

> On non-book-E-or-4xx, exceptions execute in real mode.  If a fault  
> happens
> that leads to a register dump, the kernel currently prints XXXXXXXX  
> because
> it doesn't realize that PC is a physical address.
>
> This patch checks the state of the IMMU, and if necessary converts  
> PC into a
> virtual address.
>
> Signed-off-by: Scott Wood <scottwood@freescale.com>

Acked-by: Kumar Gala <galak@kernel.crashing.org>

- k

Re: [PATCH v4] Make instruction dumping work in real mode.

[Olof Johansson]

On Thu, Sep 27, 2007 at 01:38:55PM -0500, Scott Wood wrote:
> On non-book-E-or-4xx, exceptions execute in real mode.  If a fault happens
> that leads to a register dump, the kernel currently prints XXXXXXXX because
> it doesn't realize that PC is a physical address.
> 
> This patch checks the state of the IMMU, and if necessary converts PC into a
> virtual address.
> 
> Signed-off-by: Scott Wood <scottwood@freescale.com>

Acked-by: Olof Johansson <olof@lixom.net>


-Olof

Re: [PATCH v4] Make instruction dumping work in real mode.

[Michael Ellerman]

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On Thu, 2007-09-27 at 13:38 -0500, Scott Wood wrote:
> On non-book-E-or-4xx, exceptions execute in real mode.  If a fault happens
> that leads to a register dump, the kernel currently prints XXXXXXXX because
> it doesn't realize that PC is a physical address.
> 
> This patch checks the state of the IMMU, and if necessary converts PC into a
> virtual address.

IMMU ?

cheers

-- 
Michael Ellerman
OzLabs, IBM Australia Development Lab

wwweb: http://michael.ellerman.id.au
phone: +61 2 6212 1183 (tie line 70 21183)

We do not inherit the earth from our ancestors,
we borrow it from our children. - S.M.A.R.T Person

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Re: [PATCH v4] Make instruction dumping work in real mode.

[Scott Wood]

Michael Ellerman wrote:
> On Thu, 2007-09-27 at 13:38 -0500, Scott Wood wrote:
>> On non-book-E-or-4xx, exceptions execute in real mode.  If a fault happens
>> that leads to a register dump, the kernel currently prints XXXXXXXX because
>> it doesn't realize that PC is a physical address.
>>
>> This patch checks the state of the IMMU, and if necessary converts PC into a
>> virtual address.
> 
> IMMU ?

Instruction Memory Management Unit.

-Scott

Re: [PATCH v4] Make instruction dumping work in real mode.

[Segher Boessenkool]

> On non-book-E-or-4xx, exceptions execute in real mode.  If a fault 
> happens
> that leads to a register dump, the kernel currently prints XXXXXXXX 
> because
> it doesn't realize that PC is a physical address.
>
> This patch checks the state of the IMMU, and if necessary converts PC 
> into a
> virtual address.
>
> Signed-off-by: Scott Wood <scottwood@freescale.com>
> ---
> OK, just CONFIG_BOOKE this time. :-P

You forgot to fix the commit message ;-P


Segher