From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from gate.crashing.org (gate.crashing.org [63.228.1.57]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id E00F7B6F13 for ; Fri, 16 Mar 2012 09:28:00 +1100 (EST) Received: from [IPv6:::1] (localhost.localdomain [127.0.0.1]) by gate.crashing.org (8.14.1/8.13.8) with ESMTP id q2FMRt76014728 for ; Thu, 15 Mar 2012 17:27:56 -0500 Message-ID: <1331850475.3105.152.camel@pasglop> Subject: [PATCH] powerpc: Fix power4/970 idle code regression with lockdep From: Benjamin Herrenschmidt To: linuxppc-dev Date: Fri, 16 Mar 2012 09:27:55 +1100 Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , in commit 7230c5644188cd9e3fb380cc97dde00c464a3ba7 "powerpc: Rework lazy-interrupt handling" I introduced a regression, accidentally calling irq tracing twice and not properly restoring a clobbered register (r7) later used for writing to the MSR. This caused lockups when booting on a G5 with lockdep enabled. Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/kernel/idle_power4.S | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/arch/powerpc/kernel/idle_power4.S b/arch/powerpc/kernel/idle_power4.S index d8cdba4c2..2c71b0f 100644 --- a/arch/powerpc/kernel/idle_power4.S +++ b/arch/powerpc/kernel/idle_power4.S @@ -50,9 +50,9 @@ END_FTR_SECTION_IFCLR(CPU_FTR_CAN_NAP) addi r1,r1,128 ld r0,16(r1) mtlr r0 + mfmsr r7 #endif /* CONFIG_TRACE_IRQFLAGS */ - TRACE_ENABLE_INTS li r0,1 stb r0,PACASOFTIRQEN(r13) /* we'll hard-enable shortly */ BEGIN_FTR_SECTION -- 1.7.9