[ 16/73] ARM: 7325/1: fix v7 boot with lockdep enabled
From: Greg KH <gregkh@linuxfoundation.org>
Date: 2012-02-28 01:06:14
Also in:
lkml
3.0-stable review patch. If anyone has any objections, please let me know.
------------------
From: Rabin Vincent <redacted>
commit 8e43a905dd574f54c5715d978318290ceafbe275 upstream.
Bootup with lockdep enabled has been broken on v7 since b46c0f74657d
("ARM: 7321/1: cache-v7: Disable preemption when reading CCSIDR").
This is because v7_setup (which is called very early during boot) calls
v7_flush_dcache_all, and the save_and_disable_irqs added by that patch
ends up attempting to call into lockdep C code (trace_hardirqs_off())
when we are in no position to execute it (no stack, MMU off).
Fix this by using a notrace variant of save_and_disable_irqs. The code
already uses the notrace variant of restore_irqs.
Reviewed-by: Nicolas Pitre <redacted>
Acked-by: Stephen Boyd <redacted>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Rabin Vincent <redacted>
Signed-off-by: Russell King <redacted>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
arch/arm/include/asm/assembler.h | 5 +++++
arch/arm/mm/cache-v7.S | 2 +-
2 files changed, 6 insertions(+), 1 deletion(-)
--- a/arch/arm/include/asm/assembler.h
+++ b/arch/arm/include/asm/assembler.h@@ -137,6 +137,11 @@ disable_irq .endm + .macro save_and_disable_irqs_notrace, oldcpsr + mrs \oldcpsr, cpsr + disable_irq_notrace + .endm + /* * Restore interrupt state previously stored in a register. We don't * guarantee that this will preserve the flags. --- a/arch/arm/mm/cache-v7.S +++ b/arch/arm/mm/cache-v7.S
@@ -55,7 +55,7 @@ loop1: cmp r1, #2 @ see what cache we have at this level blt skip @ skip if no cache, or just i-cache #ifdef CONFIG_PREEMPT - save_and_disable_irqs r9 @ make cssr&csidr read atomic + save_and_disable_irqs_notrace r9 @ make cssr&csidr read atomic #endif mcr p15, 2, r10, c0, c0, 0 @ select current cache level in cssr isb @ isb to sych the new cssr&csidr