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Message-ID: <b5819922-60e0-4701-84d4-05c76d2ea5ec@acm.org>
Date:   Wed, 6 Dec 2023 14:59:00 -1000
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Subject: Re: [PATCH v3 2/3] scsi: ufs: core: Add UFS RTC support
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To:     Bean Huo <beanhuo@iokpp.de>, avri.altman@wdc.com,
        alim.akhtar@samsung.com, jejb@linux.ibm.com,
        martin.petersen@oracle.com, mani@kernel.org, quic_cang@quicinc.com,
        quic_asutoshd@quicinc.com, beanhuo@micron.com, thomas@t-8ch.de
Cc:     linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org,
        mikebi@micron.com, lporzio@micron.com
References: <20231202160227.766529-1-beanhuo@iokpp.de>
 <20231202160227.766529-3-beanhuo@iokpp.de>
From:   Bart Van Assche <bvanassche@acm.org>
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On 12/2/23 06:02, Bean Huo wrote:
> +static int ufshcd_update_rtc(struct ufs_hba *hba)
> +{
> +	int err;
> +	u32 val;
> +	struct timespec64 ts64;
> +
> +	ktime_get_real_ts64(&ts64);
> +	val = ts64.tv_sec - hba->dev_info.rtc_time_baseline;

A 64-bit value is truncated to a 32-bit value. What should happen if the
right hand side is larger than what fits into a 32-bit integer? Should
a comment perhaps be added that uptimes of more than 136 years are not
supported and also for absolute times that the above code fails after
the year 2010 + 136 = 2146?

Thanks,

Bart.