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Message-ID: <e72bfef3-53c2-4b82-382f-4a22e864169e@quicinc.com>
Date:   Fri, 8 Apr 2022 11:30:29 -0700
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Subject: Re: [PATCH v2] bus: mhi: host: pci_generic: Flush recovery worker
 during freeze
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To:     Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>,
        <mhi@lists.linux.dev>
CC:     <quic_hemantk@quicinc.com>, <linux-arm-msm@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>, <loic.poulain@linaro.org>,
        <stable@vger.kernel.org>
References: <20220408150039.17297-1-manivannan.sadhasivam@linaro.org>
From:   Bhaumik Vasav Bhatt <quic_bbhatt@quicinc.com>
In-Reply-To: <20220408150039.17297-1-manivannan.sadhasivam@linaro.org>
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On 4/8/2022 8:00 AM, Manivannan Sadhasivam wrote:
> It is possible that the recovery work might be running while the freeze
> gets executed (during hibernation etc.,). Currently, we don't powerdown
> the stack if it is not up but if the recovery work completes after freeze,
> then the device will be up afterwards. This will not be a sane situation.
>
> So let's flush the recovery worker before trying to powerdown the device.
>
> Cc: stable@vger.kernel.org
> Fixes: 5f0c2ee1fe8d ("bus: mhi: pci-generic: Fix hibernation")
> Reported-by: Bhaumik Vasav Bhatt <quic_bbhatt@quicinc.com>
> Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
> ---
Reviewed-by: Bhaumik Vasav Bhatt <quic_bbhatt@quicinc.com>
> Changes in v2:
>
> * Switched to flush_work() as the workqueue used is global one.
>
>   drivers/bus/mhi/host/pci_generic.c | 1 +
>   1 file changed, 1 insertion(+)
>
> diff --git a/drivers/bus/mhi/host/pci_generic.c b/drivers/bus/mhi/host/pci_generic.c
> index ef85dbfb3216..541ced27d941 100644
> --- a/drivers/bus/mhi/host/pci_generic.c
> +++ b/drivers/bus/mhi/host/pci_generic.c
> @@ -1060,6 +1060,7 @@ static int __maybe_unused mhi_pci_freeze(struct device *dev)
>   	 * the intermediate restore kernel reinitializes MHI device with new
>   	 * context.
>   	 */
> +	flush_work(&mhi_pdev->recovery_work);
>   	if (test_and_clear_bit(MHI_PCI_DEV_STARTED, &mhi_pdev->status)) {
>   		mhi_power_down(mhi_cntrl, true);
>   		mhi_unprepare_after_power_down(mhi_cntrl);