From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753860AbdDLQ4D (ORCPT ); Wed, 12 Apr 2017 12:56:03 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:49573 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752383AbdDLQz6 (ORCPT ); Wed, 12 Apr 2017 12:55:58 -0400 From: "Paul E. McKenney" To: linux-kernel@vger.kernel.org Cc: mingo@kernel.org, jiangshanlai@gmail.com, dipankar@in.ibm.com, akpm@linux-foundation.org, mathieu.desnoyers@efficios.com, josh@joshtriplett.org, tglx@linutronix.de, peterz@infradead.org, rostedt@goodmis.org, dhowells@redhat.com, edumazet@google.com, fweisbec@gmail.com, oleg@redhat.com, bobby.prani@gmail.com, "Paul E. McKenney" Subject: [PATCH tip/core/rcu 02/13] lockdep: Use "WARNING" tag on lockdep splats Date: Wed, 12 Apr 2017 09:55:38 -0700 X-Mailer: git-send-email 2.5.2 In-Reply-To: <20170412165441.GA17149@linux.vnet.ibm.com> References: <20170412165441.GA17149@linux.vnet.ibm.com> X-TM-AS-GCONF: 00 x-cbid: 17041216-0044-0000-0000-0000030303E8 X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00006924; HX=3.00000240; KW=3.00000007; PH=3.00000004; SC=3.00000208; SDB=6.00846589; UDB=6.00417599; IPR=6.00625026; BA=6.00005286; NDR=6.00000001; ZLA=6.00000005; ZF=6.00000009; ZB=6.00000000; ZP=6.00000000; ZH=6.00000000; ZU=6.00000002; MB=3.00015022; XFM=3.00000013; UTC=2017-04-12 16:55:56 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 17041216-0045-0000-0000-000007310686 Message-Id: <1492016149-18834-2-git-send-email-paulmck@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2017-04-12_13:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=1 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1702020001 definitions=main-1704120138 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This commit changes lockdep splats to begin lines with "WARNING" and to use pr_warn() instead of printk(). This change eases scripted analysis of kernel console output. Reported-by: Dmitry Vyukov Reported-by: Ingo Molnar Signed-off-by: Paul E. McKenney Acked-by: Dmitry Vyukov --- kernel/locking/lockdep.c | 86 +++++++++++++++++++++--------------------- kernel/locking/rtmutex-debug.c | 9 +++-- 2 files changed, 48 insertions(+), 47 deletions(-) diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c index a95e5d1f4a9c..e9d4f85b290c 100644 --- a/kernel/locking/lockdep.c +++ b/kernel/locking/lockdep.c @@ -1144,10 +1144,10 @@ print_circular_bug_header(struct lock_list *entry, unsigned int depth, return 0; printk("\n"); - printk("======================================================\n"); - printk("[ INFO: possible circular locking dependency detected ]\n"); + pr_warn("======================================================\n"); + pr_warn("WARNING: possible circular locking dependency detected\n"); print_kernel_ident(); - printk("-------------------------------------------------------\n"); + pr_warn("------------------------------------------------------\n"); printk("%s/%d is trying to acquire lock:\n", curr->comm, task_pid_nr(curr)); print_lock(check_src); @@ -1482,11 +1482,11 @@ print_bad_irq_dependency(struct task_struct *curr, return 0; printk("\n"); - printk("======================================================\n"); - printk("[ INFO: %s-safe -> %s-unsafe lock order detected ]\n", + pr_warn("=====================================================\n"); + pr_warn("WARNING: %s-safe -> %s-unsafe lock order detected\n", irqclass, irqclass); print_kernel_ident(); - printk("------------------------------------------------------\n"); + pr_warn("-----------------------------------------------------\n"); printk("%s/%d [HC%u[%lu]:SC%u[%lu]:HE%u:SE%u] is trying to acquire:\n", curr->comm, task_pid_nr(curr), curr->hardirq_context, hardirq_count() >> HARDIRQ_SHIFT, @@ -1711,10 +1711,10 @@ print_deadlock_bug(struct task_struct *curr, struct held_lock *prev, return 0; printk("\n"); - printk("=============================================\n"); - printk("[ INFO: possible recursive locking detected ]\n"); + pr_warn("============================================\n"); + pr_warn("WARNING: possible recursive locking detected\n"); print_kernel_ident(); - printk("---------------------------------------------\n"); + pr_warn("--------------------------------------------\n"); printk("%s/%d is trying to acquire lock:\n", curr->comm, task_pid_nr(curr)); print_lock(next); @@ -2061,10 +2061,10 @@ static void print_collision(struct task_struct *curr, struct lock_chain *chain) { printk("\n"); - printk("======================\n"); - printk("[chain_key collision ]\n"); + pr_warn("============================\n"); + pr_warn("WARNING: chain_key collision\n"); print_kernel_ident(); - printk("----------------------\n"); + pr_warn("----------------------------\n"); printk("%s/%d: ", current->comm, task_pid_nr(current)); printk("Hash chain already cached but the contents don't match!\n"); @@ -2360,10 +2360,10 @@ print_usage_bug(struct task_struct *curr, struct held_lock *this, return 0; printk("\n"); - printk("=================================\n"); - printk("[ INFO: inconsistent lock state ]\n"); + pr_warn("================================\n"); + pr_warn("WARNING: inconsistent lock state\n"); print_kernel_ident(); - printk("---------------------------------\n"); + pr_warn("--------------------------------\n"); printk("inconsistent {%s} -> {%s} usage.\n", usage_str[prev_bit], usage_str[new_bit]); @@ -2425,10 +2425,10 @@ print_irq_inversion_bug(struct task_struct *curr, return 0; printk("\n"); - printk("=========================================================\n"); - printk("[ INFO: possible irq lock inversion dependency detected ]\n"); + pr_warn("========================================================\n"); + pr_warn("WARNING: possible irq lock inversion dependency detected\n"); print_kernel_ident(); - printk("---------------------------------------------------------\n"); + pr_warn("--------------------------------------------------------\n"); printk("%s/%d just changed the state of lock:\n", curr->comm, task_pid_nr(curr)); print_lock(this); @@ -3170,10 +3170,10 @@ print_lock_nested_lock_not_held(struct task_struct *curr, return 0; printk("\n"); - printk("==================================\n"); - printk("[ BUG: Nested lock was not taken ]\n"); + pr_warn("==================================\n"); + pr_warn("WARNING: Nested lock was not taken\n"); print_kernel_ident(); - printk("----------------------------------\n"); + pr_warn("----------------------------------\n"); printk("%s/%d is trying to lock:\n", curr->comm, task_pid_nr(curr)); print_lock(hlock); @@ -3383,10 +3383,10 @@ print_unlock_imbalance_bug(struct task_struct *curr, struct lockdep_map *lock, return 0; printk("\n"); - printk("=====================================\n"); - printk("[ BUG: bad unlock balance detected! ]\n"); + pr_warn("=====================================\n"); + pr_warn("WARNING: bad unlock balance detected!\n"); print_kernel_ident(); - printk("-------------------------------------\n"); + pr_warn("-------------------------------------\n"); printk("%s/%d is trying to release lock (", curr->comm, task_pid_nr(curr)); print_lockdep_cache(lock); @@ -3880,10 +3880,10 @@ print_lock_contention_bug(struct task_struct *curr, struct lockdep_map *lock, return 0; printk("\n"); - printk("=================================\n"); - printk("[ BUG: bad contention detected! ]\n"); + pr_warn("=================================\n"); + pr_warn("WARNING: bad contention detected!\n"); print_kernel_ident(); - printk("---------------------------------\n"); + pr_warn("---------------------------------\n"); printk("%s/%d is trying to contend lock (", curr->comm, task_pid_nr(curr)); print_lockdep_cache(lock); @@ -4244,10 +4244,10 @@ print_freed_lock_bug(struct task_struct *curr, const void *mem_from, return; printk("\n"); - printk("=========================\n"); - printk("[ BUG: held lock freed! ]\n"); + pr_warn("=========================\n"); + pr_warn("WARNING: held lock freed!\n"); print_kernel_ident(); - printk("-------------------------\n"); + pr_warn("-------------------------\n"); printk("%s/%d is freeing memory %p-%p, with a lock still held there!\n", curr->comm, task_pid_nr(curr), mem_from, mem_to-1); print_lock(hlock); @@ -4302,11 +4302,11 @@ static void print_held_locks_bug(void) return; printk("\n"); - printk("=====================================\n"); - printk("[ BUG: %s/%d still has locks held! ]\n", + pr_warn("====================================\n"); + pr_warn("WARNING: %s/%d still has locks held!\n", current->comm, task_pid_nr(current)); print_kernel_ident(); - printk("-------------------------------------\n"); + pr_warn("------------------------------------\n"); lockdep_print_held_locks(current); printk("\nstack backtrace:\n"); dump_stack(); @@ -4371,7 +4371,7 @@ void debug_show_all_locks(void) } while_each_thread(g, p); printk("\n"); - printk("=============================================\n\n"); + pr_warn("=============================================\n\n"); if (unlock) read_unlock(&tasklist_lock); @@ -4401,10 +4401,10 @@ asmlinkage __visible void lockdep_sys_exit(void) if (!debug_locks_off()) return; printk("\n"); - printk("================================================\n"); - printk("[ BUG: lock held when returning to user space! ]\n"); + pr_warn("================================================\n"); + pr_warn("WARNING: lock held when returning to user space!\n"); print_kernel_ident(); - printk("------------------------------------------------\n"); + pr_warn("------------------------------------------------\n"); printk("%s/%d is leaving the kernel with locks still held!\n", curr->comm, curr->pid); lockdep_print_held_locks(curr); @@ -4421,13 +4421,13 @@ void lockdep_rcu_suspicious(const char *file, const int line, const char *s) #endif /* #ifdef CONFIG_PROVE_RCU_REPEATEDLY */ /* Note: the following can be executed concurrently, so be careful. */ printk("\n"); - pr_err("===============================\n"); - pr_err("[ ERR: suspicious RCU usage. ]\n"); + pr_warn("=============================\n"); + pr_warn("WARNING: suspicious RCU usage\n"); print_kernel_ident(); - pr_err("-------------------------------\n"); - pr_err("%s:%d %s!\n", file, line, s); - pr_err("\nother info that might help us debug this:\n\n"); - pr_err("\n%srcu_scheduler_active = %d, debug_locks = %d\n", + pr_warn("-----------------------------\n"); + printk("%s:%d %s!\n", file, line, s); + printk("\nother info that might help us debug this:\n\n"); + printk("\n%srcu_scheduler_active = %d, debug_locks = %d\n", !rcu_lockdep_current_cpu_online() ? "RCU used illegally from offline CPU!\n" : !rcu_is_watching() diff --git a/kernel/locking/rtmutex-debug.c b/kernel/locking/rtmutex-debug.c index 97ee9df32e0f..db4f55211b04 100644 --- a/kernel/locking/rtmutex-debug.c +++ b/kernel/locking/rtmutex-debug.c @@ -102,10 +102,11 @@ void debug_rt_mutex_print_deadlock(struct rt_mutex_waiter *waiter) return; } - printk("\n============================================\n"); - printk( "[ BUG: circular locking deadlock detected! ]\n"); - printk("%s\n", print_tainted()); - printk( "--------------------------------------------\n"); + pr_warn("\n"); + pr_warn("============================================\n"); + pr_warn("WARNING: circular locking deadlock detected!\n"); + pr_warn("%s\n", print_tainted()); + pr_warn("--------------------------------------------\n"); printk("%s/%d is deadlocking current task %s/%d\n\n", task->comm, task_pid_nr(task), current->comm, task_pid_nr(current)); -- 2.5.2