Commit da6731e7 authored by Xiongfeng Wang's avatar Xiongfeng Wang Committed by Zheng Zengkai
Browse files

stop_machine: mask sdei before running the callback 

hulk inclusion
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I4JBQ8



----------------------------------------

Kprobes use 'stop_machine' to modify code which could be ran in the
sdei_handler at the same time. This patch mask sdei before running the
stop_machine callback to avoid this race condition.

Signed-off-by: default avatarXiongfeng Wang <wangxiongfeng2@huawei.com>
Reviewed-by: default avatarYang Yingliang <yangyingliang@huawei.com>
Signed-off-by: default avatarWei Li <liwei391@huawei.com>
Reviewed-by: default avatarCheng Jian <cj.chengjian@huawei.com>
Signed-off-by: default avatarZheng Zengkai <zhengzengkai@huawei.com>
parent 02693e3f

kernel/stop_machine.c

+10 −0
Original line number Diff line number Diff line
@@ -23,6 +23,10 @@ 
#include <linux/nmi.h>

#include <linux/sched/wake_q.h>



#ifdef CONFIG_ARM64

#include <linux/arm_sdei.h>

#endif



/*

 * Structure to determine completion condition and record errors.  May

 * be shared by works on different cpus.
@@ -218,6 +222,9 @@ static int multi_cpu_stop(void *data) 
			case MULTI_STOP_DISABLE_IRQ:

				local_irq_disable();

				hard_irq_disable();

#ifdef CONFIG_ARM64

				sdei_mask_local_cpu();

#endif

				break;

			case MULTI_STOP_RUN:

				if (is_active)
@@ -238,6 +245,9 @@ static int multi_cpu_stop(void *data) 
		rcu_momentary_dyntick_idle();

	} while (curstate != MULTI_STOP_EXIT);



#ifdef CONFIG_ARM64

	sdei_unmask_local_cpu();

#endif

	local_irq_restore(flags);

	return err;

}