lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Mon, 23 Nov 2015 15:19:38 +0800 From: <jianchuan.wang@...driver.com> To: <rostedt@...dmis.org>, <bigeasy@...utronix.de>, <tglx@...utronix.de>, <yang.shi@...driver.com> CC: <linux-rt-users@...r.kernel.org>, <linux-kernel@...r.kernel.org> Subject: [PATCH] locking_selftest: Save/restore migrate_disable_atomic in locking selftest From: Jianchuan Wang <jianchuan.wang@...driver.com> System will hang when enabling the kernel option CONFIG_DEBUG_LOCKING_API_SELFTESTS and CONFIG_SCHED_CONFIG in the preempt-rt kernel. In the preempt-rt kernel, migrate_enable()/migrage_disable() are called in the spinlock and read/write lock; The lock()/unlock() aren't used in pairs in the selftest processing changes the migrate_disable_atomic so that the system will hang in the dotest(), the calltrace is : printk() ..-> vprintk_emit() -> migrage_disable() -> WARN_ON_ONCE() ..-> warn_slowpath_common() ..-> printk() For fixing it, we need save the migrate_disable_atomic before self-testing and restore migrate_disable_atomic after self-testing. Signed-off-by: Jianchuan Wang <jianchuan.wang@...driver.com> --- lib/locking-selftest.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/lib/locking-selftest.c b/lib/locking-selftest.c index b93a610..61798da 100644 --- a/lib/locking-selftest.c +++ b/lib/locking-selftest.c @@ -997,10 +997,23 @@ static int unexpected_testcase_failures; static void dotest(void (*testcase_fn)(void), int expected, int lockclass_mask) { unsigned long saved_preempt_count = preempt_count(); +#ifdef CONFIG_SCHED_DEBUG + struct task_struct *p = current; + int save_migrate_atomic; +#endif WARN_ON(irqs_disabled()); +#ifdef CONFIG_SCHED_DEBUG + save_migrate_atomic = p->migrate_disable_atomic; +#endif + testcase_fn(); + +#ifdef CONFIG_SCHED_DEBUG + p->migrate_disable_atomic = save_migrate_atomic; +#endif + /* * Filter out expected failures: */ -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists