From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752925Ab1AUCL1 (ORCPT ); Thu, 20 Jan 2011 21:11:27 -0500 Received: from mx3.mail.elte.hu ([157.181.1.138]:60194 "EHLO mx3.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750856Ab1AUCL0 (ORCPT ); Thu, 20 Jan 2011 21:11:26 -0500 Date: Fri, 21 Jan 2011 03:11:17 +0100 From: Ingo Molnar To: Linus Torvalds Cc: linux-kernel@vger.kernel.org, Peter Zijlstra , Tejun Heo , Thomas Gleixner , Andrew Morton Subject: [GIT PULL] core kernel fixes Message-ID: <20110121021117.GA31309@elte.hu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.20 (2009-08-17) X-ELTE-SpamScore: -2.0 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-2.0 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.2.5 -2.0 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Linus, Please pull the latest core-fixes-for-linus git tree from: git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip.git core-fixes-for-linus This fixes the percpu related boot crash that i've reported. Thanks, Ingo ------------------> Tejun Heo (2): lockdep: Move early boot local IRQ enable/disable status to init/main.c smp: Allow on_each_cpu() to be called while early_boot_irqs_disabled status to init/main.c arch/x86/xen/enlighten.c | 2 +- include/linux/kernel.h | 2 ++ include/linux/lockdep.h | 8 -------- init/main.c | 13 +++++++++++-- kernel/lockdep.c | 18 +----------------- kernel/smp.c | 11 +++++++---- kernel/trace/trace_irqsoff.c | 8 -------- 7 files changed, 22 insertions(+), 40 deletions(-) diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c index 7e8d3bc..50542ef 100644 --- a/arch/x86/xen/enlighten.c +++ b/arch/x86/xen/enlighten.c @@ -1194,7 +1194,7 @@ asmlinkage void __init xen_start_kernel(void) per_cpu(xen_vcpu, 0) = &HYPERVISOR_shared_info->vcpu_info[0]; local_irq_disable(); - early_boot_irqs_off(); + early_boot_irqs_disabled = true; memblock_init(); diff --git a/include/linux/kernel.h b/include/linux/kernel.h index 5a9d905..d07d805 100644 --- a/include/linux/kernel.h +++ b/include/linux/kernel.h @@ -243,6 +243,8 @@ extern int test_taint(unsigned flag); extern unsigned long get_taint(void); extern int root_mountflags; +extern bool early_boot_irqs_disabled; + /* Values used for system_state */ extern enum system_states { SYSTEM_BOOTING, diff --git a/include/linux/lockdep.h b/include/linux/lockdep.h index 71c09b2..f638fd7 100644 --- a/include/linux/lockdep.h +++ b/include/linux/lockdep.h @@ -436,16 +436,8 @@ do { \ #endif /* CONFIG_LOCKDEP */ #ifdef CONFIG_TRACE_IRQFLAGS -extern void early_boot_irqs_off(void); -extern void early_boot_irqs_on(void); extern void print_irqtrace_events(struct task_struct *curr); #else -static inline void early_boot_irqs_off(void) -{ -} -static inline void early_boot_irqs_on(void) -{ -} static inline void print_irqtrace_events(struct task_struct *curr) { } diff --git a/init/main.c b/init/main.c index 00799c1..33c37c3 100644 --- a/init/main.c +++ b/init/main.c @@ -96,6 +96,15 @@ static inline void mark_rodata_ro(void) { } extern void tc_init(void); #endif +/* + * Debug helper: via this flag we know that we are in 'early bootup code' + * where only the boot processor is running with IRQ disabled. This means + * two things - IRQ must not be enabled before the flag is cleared and some + * operations which are not allowed with IRQ disabled are allowed while the + * flag is set. + */ +bool early_boot_irqs_disabled __read_mostly; + enum system_states system_state __read_mostly; EXPORT_SYMBOL(system_state); @@ -554,7 +563,7 @@ asmlinkage void __init start_kernel(void) cgroup_init_early(); local_irq_disable(); - early_boot_irqs_off(); + early_boot_irqs_disabled = true; /* * Interrupts are still disabled. Do necessary setups, then @@ -621,7 +630,7 @@ asmlinkage void __init start_kernel(void) if (!irqs_disabled()) printk(KERN_CRIT "start_kernel(): bug: interrupts were " "enabled early\n"); - early_boot_irqs_on(); + early_boot_irqs_disabled = false; local_irq_enable(); /* Interrupts are enabled now so all GFP allocations are safe. */ diff --git a/kernel/lockdep.c b/kernel/lockdep.c index 42ba65d..0d2058d 100644 --- a/kernel/lockdep.c +++ b/kernel/lockdep.c @@ -2292,22 +2292,6 @@ mark_held_locks(struct task_struct *curr, enum mark_type mark) } /* - * Debugging helper: via this flag we know that we are in - * 'early bootup code', and will warn about any invalid irqs-on event: - */ -static int early_boot_irqs_enabled; - -void early_boot_irqs_off(void) -{ - early_boot_irqs_enabled = 0; -} - -void early_boot_irqs_on(void) -{ - early_boot_irqs_enabled = 1; -} - -/* * Hardirqs will be enabled: */ void trace_hardirqs_on_caller(unsigned long ip) @@ -2319,7 +2303,7 @@ void trace_hardirqs_on_caller(unsigned long ip) if (unlikely(!debug_locks || current->lockdep_recursion)) return; - if (DEBUG_LOCKS_WARN_ON(unlikely(!early_boot_irqs_enabled))) + if (DEBUG_LOCKS_WARN_ON(unlikely(early_boot_irqs_disabled))) return; if (unlikely(curr->hardirqs_enabled)) { diff --git a/kernel/smp.c b/kernel/smp.c index 4ec30e0..4b83cd6 100644 --- a/kernel/smp.c +++ b/kernel/smp.c @@ -430,7 +430,7 @@ void smp_call_function_many(const struct cpumask *mask, * can't happen. */ WARN_ON_ONCE(cpu_online(this_cpu) && irqs_disabled() - && !oops_in_progress); + && !oops_in_progress && !early_boot_irqs_disabled); /* So, what's a CPU they want? Ignoring this one. */ cpu = cpumask_first_and(mask, cpu_online_mask); @@ -533,17 +533,20 @@ void ipi_call_unlock_irq(void) #endif /* USE_GENERIC_SMP_HELPERS */ /* - * Call a function on all processors + * Call a function on all processors. May be used during early boot while + * early_boot_irqs_disabled is set. Use local_irq_save/restore() instead + * of local_irq_disable/enable(). */ int on_each_cpu(void (*func) (void *info), void *info, int wait) { + unsigned long flags; int ret = 0; preempt_disable(); ret = smp_call_function(func, info, wait); - local_irq_disable(); + local_irq_save(flags); func(info); - local_irq_enable(); + local_irq_restore(flags); preempt_enable(); return ret; } diff --git a/kernel/trace/trace_irqsoff.c b/kernel/trace/trace_irqsoff.c index 5cf8c60..92b6e1e 100644 --- a/kernel/trace/trace_irqsoff.c +++ b/kernel/trace/trace_irqsoff.c @@ -453,14 +453,6 @@ void time_hardirqs_off(unsigned long a0, unsigned long a1) * Stubs: */ -void early_boot_irqs_off(void) -{ -} - -void early_boot_irqs_on(void) -{ -} - void trace_softirqs_on(unsigned long ip) { }