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To:     <sergey.senozhatsky@gmail.com>, <linuxarm@huawei.com>,
        <linux-kernel@vger.kernel.org>
From:   Yao HongBo <yaohongbo@huawei.com>
Subject: possible deadlock in console_unlock
Message-ID: <ebc01f4f-5b1d-4f8a-1d0d-463d5218ee45@huawei.com>
Date:   Sat, 16 Feb 2019 14:36:48 +0800
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Sender: linux-kernel-owner@vger.kernel.org
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hi, sergey:

As shown in that link, https://lkml.org/lkml/2018/6/6/397

On the linux kernel 5.0-rc6, Syzkaller also hit 'possible deadlock in console_unlock'
bug for several times in my environment.

This solution fixes things for me. Do you have a plan to submit patches to
solve this problem.

diff --git a/drivers/tty/tty_buffer.c b/drivers/tty/tty_buffer.c
	__printk_safe_enter();
	kmalloc(sizeof(struct tty_buffer) + 2 * size, GFP_ATOMIC);
	__printk_safe_exit();


Best regards,
Hongbo