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Date: Fri, 19 Apr 2024 13:05:48 +0530
User-Agent: Mozilla Thunderbird
Subject: Re: [bug-report] task info hung problem in fb_deferred_io_work()
To: Nam Cao <namcao@linutronix.de>
Cc: Daniel Vetter <daniel@ffwll.ch>, deller@gmx.de,
        linux-fbdev@vger.kernel.org, dri-devel@lists.freedesktop.org,
        tiwai@suse.de, bigeasy@linutronix.de, patrik.r.jakobsson@gmail.com,
        LKML <linux-kernel@vger.kernel.org>,
        Vegard Nossum
 <vegard.nossum@oracle.com>,
        George Kennedy <george.kennedy@oracle.com>,
        Darren Kenny <darren.kenny@oracle.com>, chuansheng.liu@intel.com
References: <271372d6-e665-4e7f-b088-dee5f4ab341a@oracle.com>
 <20240418160652.68df1a86@namcao>
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From: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
In-Reply-To: <20240418160652.68df1a86@namcao>
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Hi Nam,

On 18/04/24 19:36, Nam Cao wrote:
> On 2024-04-18 Harshit Mogalapalli wrote:
>> While fuzzing 5.15.y kernel with Syzkaller, we noticed a INFO: task hung
>> bug in fb_deferred_io_work()
> 
> Which framebuffer device are you using exactly? It is possible that
> the problem is with the device driver, not core framebuffer.
> 

I am not very sure about the answer, but the C reproducer uses(/dev/fb0)

int fd = open("/dev/fb0", O_RDWR, 0);

Thanks,
Harshit

> Best regards,
> Nam