linux-kernel - Re: [PATCH 1/1] iio: imx8qxp-adc: fix irq flood when call imx8qxp_adc_read

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <bbacb73a-6904-d196-ab4a-3e388bcab56c@metafoo.de>
Date:   Tue, 29 Nov 2022 10:23:04 -0800
From:   Lars-Peter Clausen <lars@...afoo.de>
To:     Frank Li <Frank.Li@....com>, Cai Huoqing <cai.huoqing@...ux.dev>,
        Haibo Chen <haibo.chen@....com>,
        Jonathan Cameron <jic23@...nel.org>,
        Shawn Guo <shawnguo@...nel.org>,
        Sascha Hauer <s.hauer@...gutronix.de>,
        Pengutronix Kernel Team <kernel@...gutronix.de>,
        Fabio Estevam <festevam@...il.com>,
        NXP Linux Team <linux-imx@....com>,
        "open list:NXP i.MX 8QXP ADC DRIVER" <linux-iio@...r.kernel.org>,
        "moderated list:ARM/FREESCALE IMX / MXC ARM ARCHITECTURE" 
        <linux-arm-kernel@...ts.infradead.org>,
        open list <linux-kernel@...r.kernel.org>
Cc:     imx@...ts.linux.dev
Subject: Re: [PATCH 1/1] iio: imx8qxp-adc: fix irq flood when call
 imx8qxp_adc_read_raw()

On 11/29/22 08:45, Frank Li wrote:
		       readl(adc->regs + IMX8QXP_ADR_ADC_FCTRL));
> @@ -272,6 +275,10 @@ static irqreturn_t imx8qxp_adc_isr(int irq, void *dev_id)
>   	if (fifo_count)
>   		complete(&adc->completion);

Shouldn't the completion be triggered after the reading of the samples? 
otherwise you have a race condition on a multi-processor system.

>   
> +	for (i = 0; i < fifo_count; i++)
> +		adc->fifo[i] = FIELD_GET(IMX8QXP_ADC_RESFIFO_VAL_MASK,
> +				readl_relaxed(adc->regs + IMX8QXP_ADR_ADC_RESFIFO));
> +
>   	return IRQ_HANDLED;
>   }
>