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Message-ID: <f945b683-dc1e-df50-adb1-5bbe41562d1e@broadcom.com>
Date:   Mon, 26 Jun 2023 10:18:15 -0700
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Subject: Re: [PATCH] i2c: bcm-iproc: Fix bcm_iproc_i2c_isr deadlock issue
To:     YE Chengfeng <cyeaa@connect.ust.hk>
Cc:     "andi.shyti@kernel.org" <andi.shyti@kernel.org>,
        "rjui@broadcom.com" <rjui@broadcom.com>,
        "sbranden@broadcom.com" <sbranden@broadcom.com>,
        "linux-i2c@vger.kernel.org" <linux-i2c@vger.kernel.org>,
        Linux ARM <linux-arm-kernel@lists.infradead.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "bcm-kernel-feedback-list@broadcom.com" 
        <bcm-kernel-feedback-list@broadcom.com>
References: <TYCP286MB1188708B1CE64D95FBACF9E78A20A@TYCP286MB1188.JPNP286.PROD.OUTLOOK.COM>
 <b68ad6c4-f5e6-9bb7-0ac8-2cd08ce04c7a@broadcom.com>
 <60931201-FD2A-4579-861E-E9573B7C2B38@connect.ust.hk>
From:   Ray Jui <ray.jui@broadcom.com>
In-Reply-To: <60931201-FD2A-4579-861E-E9573B7C2B38@connect.ust.hk>
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On 6/26/2023 10:05 AM, YE Chengfeng wrote:
>> This fix looks good to me. Thanks. Just curious, did you actually see a
>> race condition issue as a result of this, or the fix is done completely
>> based on the analysis of the code?
> 
> Thanks for the reply!
> 
> This bug is detected by a static analysis tool built by me, I just notice I should 
> mention this in the commit message and sorry for not have made it clear. I noticed 
> lockdep occasionally reported such similar deadlocks in other place thus built the 
> static tool to locate such bugs.
> 
> Just feel free to let me know if anything in the patch should be improved.
> 
> Best Regards,
> Chengfeng

This sounds good. Thanks again, Chengfeng!

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