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([2402:f000:1:4414:a441:1820:9cbd:367b]) by smtp.gmail.com with ESMTPSA id o24-v6sm36365574pfa.90.2018.10.10.00.31.52 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 10 Oct 2018 00:31:53 -0700 (PDT) Subject: Re: [BUG] mfd: ezx-pcap: Possible sleep-in-atomic-context bugs in pcap_adc_irq() To: Lee Jones Cc: Linux Kernel Mailing List References: <20180917010340.GA3900@dell> <20181009090715.GE4939@dell> From: Jia-Ju Bai Message-ID: <8579fb94-aef5-7782-b062-0dc9bea29e4b@gmail.com> Date: Wed, 10 Oct 2018 15:31:48 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.2.0 MIME-Version: 1.0 In-Reply-To: <20181009090715.GE4939@dell> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2018/10/9 17:07, Lee Jones wrote: > On Mon, 17 Sep 2018, Jia-Ju Bai wrote: > >> >> On 2018/9/17 9:03, Lee Jones wrote: >>> On Sat, 15 Sep 2018, Jia-Ju Bai wrote: >>> >>>> The driver may sleep in an interrupt handler. >>>> The function call paths (from bottom to top) in Linux-4.17 are: >>>> >>>> [FUNC] mutex_lock_nested >>>> drivers/mfd/ezx-pcap.c, 272: >>>> mutex_lock_nested in pcap_adc_irq (interrupt handler) >>>> >>>> [FUNC] mutex_lock_nested >>>> drivers/mfd/ezx-pcap.c, 100: >>>> mutex_lock_nested in ezx_pcap_read >>>> drivers/mfd/ezx-pcap.c, 281: >>>> ezx_pcap_read in pcap_adc_irq (interrupt handler) >>>> >>>> [FUNC] mutex_lock_nested >>>> drivers/mfd/ezx-pcap.c, 85: >>>> mutex_lock_nested in ezx_pcap_write >>>> drivers/mfd/ezx-pcap.c, 285: >>>> ezx_pcap_write in pcap_adc_irq (interrupt handler) >>>> >>>> [FUNC] mutex_lock_nested >>>> drivers/mfd/ezx-pcap.c, 244: >>>> mutex_lock_nested in pcap_adc_trigger >>>> drivers/mfd/ezx-pcap.c, 299: >>>> pcap_adc_trigger in pcap_adc_irq (interrupt handler) >>>> >>>> These bugs are found by my static analysis tool DSAC. >>> Not sure what you want me to do with this. >>> >>> Do you have something in mind? >>> >> I find some possible bugs in this driver, but I do not know how to correctly >> fix them... >> Could you find a good solution? > If you have found bugs and do not intend on fixing them, please report > them via the 'File a Bug' option here: > > https://bugzilla.kernel.org/ > Okay, thanks. Best wishes, Jia-Ju Bai