[PATCH] ARM: Kconfig: Do not select ARCH_VEXPRESS on ARCH_MULTI_V7

[PATCH] ARM: Kconfig: Do not select ARCH_VEXPRESS on ARCH_MULTI_V7

[Fabio Estevam]

Booting a kernel on a mx53qsb board (built with imx_v6_v7_defconfig) leads to:

Unable to handle kernel NULL pointer dereference at virtual address 00000008
pgd = 80004000
[00000008] *pgd=00000000
Internal error: Oops: 805 [#1] SMP ARM
Modules linked in:
CPU: 0    Not tainted  (3.7.0-rc5-next-20121115+ #715)
PC is at vexpress_sysreg_init_leds+0x30/0xb8
LR is at do_one_initcall+0x3c/0x190
pc : [<8065e170>]    lr : [<800086a0>]    psr: 60000153
sp : df855ef0  ip : df855f18  fp : df855f14
r10: 00000000  r9 : 8067eb5c  r8 : 8065e140
r7 : 80711cac  r6 : 806c2cc0  r5 : 00000000  r4 : 80673850
r3 : 00000000  r2 : 00000000  r1 : df854000  r0 : 8065e140
...

Since commit c5a0d4977 (ARM: imx: enable multi-platform build), imx_v6_v7_defconfig
selects CONFIG_ARCH_MULTI_V7=y, which in turn select ARCH_VEXPRESS.

Do not select ARCH_VEXPRESS on ARCH_MULTI_V7.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
---
 arch/arm/Kconfig |    1 -
 1 file changed, 1 deletion(-)

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 14f8160..d40e9d3 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -1000,7 +1000,6 @@ config ARCH_MULTI_V7
 	bool "ARMv7 based platforms (Cortex-A, PJ4, Krait)"
 	default y
 	select ARCH_MULTI_V6_V7
-	select ARCH_VEXPRESS
 	select CPU_V7
 
 config ARCH_MULTI_V6_V7
-- 
1.7.9.5

[PATCH] ARM: Kconfig: Do not select ARCH_VEXPRESS on ARCH_MULTI_V7

[Pawel Moll]

On Mon, 2012-11-19 at 16:38 +0000, Fabio Estevam wrote:
> Booting a kernel on a mx53qsb board (built with imx_v6_v7_defconfig) leads to:
> 
> Unable to handle kernel NULL pointer dereference at virtual address 00000008
> pgd = 80004000
> [00000008] *pgd=00000000
> Internal error: Oops: 805 [#1] SMP ARM
> Modules linked in:
> CPU: 0    Not tainted  (3.7.0-rc5-next-20121115+ #715)
> PC is at vexpress_sysreg_init_leds+0x30/0xb8
> LR is at do_one_initcall+0x3c/0x190
> pc : [<8065e170>]    lr : [<800086a0>]    psr: 60000153
> sp : df855ef0  ip : df855f18  fp : df855f14
> r10: 00000000  r9 : 8067eb5c  r8 : 8065e140
> r7 : 80711cac  r6 : 806c2cc0  r5 : 00000000  r4 : 80673850
> r3 : 00000000  r2 : 00000000  r1 : df854000  r0 : 8065e140
> ...

It's a bug in vexpress-sysreg driver. 3 hours ago I've posted patch
removing this code...

https://patchwork.kernel.org/patch/1764801/

Apologies about causing the issue in the first place.

Pawel

[PATCH] ARM: Kconfig: Do not select ARCH_VEXPRESS on ARCH_MULTI_V7

[Thomas Petazzoni]

On Mon, 19 Nov 2012 16:44:57 +0000, Pawel Moll wrote:

> It's a bug in vexpress-sysreg driver. 3 hours ago I've posted patch
> removing this code...
> 
> https://patchwork.kernel.org/patch/1764801/
> 
> Apologies about causing the issue in the first place.

But still, the patch that Fabio raises is interesting: why would
ARCH_VEXPRESS be unconditionally enabled when building an ARM
multiplatform kernel for v6/v7 ? I may want to build a kernel with
several platforms, but not necessarily vexpress, no?

Thanks!

Thomas
-- 
Thomas Petazzoni, Free Electrons
Kernel, drivers, real-time and embedded Linux
development, consulting, training and support.
http://free-electrons.com

[PATCH] ARM: Kconfig: Do not select ARCH_VEXPRESS on ARCH_MULTI_V7

[Pawel Moll]

On Mon, 2012-11-19 at 16:54 +0000, Thomas Petazzoni wrote:
> On Mon, 19 Nov 2012 16:44:57 +0000, Pawel Moll wrote:
> 
> > It's a bug in vexpress-sysreg driver. 3 hours ago I've posted patch
> > removing this code...
> > 
> > https://patchwork.kernel.org/patch/1764801/
> > 
> > Apologies about causing the issue in the first place.
> 
> But still, the patch that Fabio raises is interesting: why would
> ARCH_VEXPRESS be unconditionally enabled when building an ARM
> multiplatform kernel for v6/v7 ? I may want to build a kernel with
> several platforms, but not necessarily vexpress, no?

I'm not arguing this. As far as I remember Rob wanted to make vexpress a
default for the multiplatform kernel, but you're right saying that
forcing it with the SELECT was probably a step too far.

Pawe?

[PATCH] ARM: Kconfig: Do not select ARCH_VEXPRESS on ARCH_MULTI_V7

[Thomas Petazzoni]

On Mon, 19 Nov 2012 16:58:59 +0000, Pawel Moll wrote:

> I'm not arguing this. As far as I remember Rob wanted to make vexpress a
> default for the multiplatform kernel, but you're right saying that
> forcing it with the SELECT was probably a step too far.

IIRC, the problem is that we need at least one platform to be enabled,
otherwise it doesn't build, but I might be wrong.

Best regards,

Thomas
-- 
Thomas Petazzoni, Free Electrons
Kernel, drivers, real-time and embedded Linux
development, consulting, training and support.
http://free-electrons.com