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From:   Dexuan-Linux Cui <dexuan.linux@gmail.com>
Date:   Thu, 4 Jun 2020 10:05:26 -0700
Message-ID: <CAA42JLat6Ern5_mztmoBX9-ONtmz=gZE3YUphY+njTa+A=efVw@mail.gmail.com>
Subject: Re: [PATCH] scsi: storvsc: Use kzfree() in storvsc_suspend()
To:     Denis Efremov <efremov@linux.com>,
        Dexuan Cui <decui@microsoft.com>,
        Michael Kelley <mikelley@microsoft.com>
Cc:     "James E.J. Bottomley" <jejb@linux.ibm.com>,
        "Martin K. Petersen" <martin.petersen@oracle.com>,
        linux-hyperv@vger.kernel.org,
        Linux SCSI List <linux-scsi@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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On Thu, Jun 4, 2020 at 6:06 AM Denis Efremov <efremov@linux.com> wrote:
>
> Use kzfree() instead of memset() with 0 followed by kfree().
>
> Signed-off-by: Denis Efremov <efremov@linux.com>
> ---
>  drivers/scsi/storvsc_drv.c | 5 +----
>  1 file changed, 1 insertion(+), 4 deletions(-)
>
> diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c
> index 072ed8728657..e5a19cd8a450 100644
> --- a/drivers/scsi/storvsc_drv.c
> +++ b/drivers/scsi/storvsc_drv.c
> @@ -2035,10 +2035,7 @@ static int storvsc_suspend(struct hv_device *hv_dev)
>
>         vmbus_close(hv_dev->channel);
>
> -       memset(stor_device->stor_chns, 0,
> -              num_possible_cpus() * sizeof(void *));
> -
> -       kfree(stor_device->stor_chns);
> +       kzfree(stor_device->stor_chns);
>         stor_device->stor_chns = NULL;
>
>         cpumask_clear(&stor_device->alloced_cpus);
> --
> 2.26.2

Hi Denis,
When I added the function storvsc_suspend() several months ago, somehow I forgot
to remove the unnecessary memset(). Sorry!

The buffer is recreated in storvsc_resume() -> storvsc_connect_to_vsp() ->
storvsc_channel_init() -> stor_device->stor_chns = kcalloc(...), so I believe
the memset() can be safely removed.  Can you please make a v2 patch for it
and Cc my corporate email "decui" (in To)?

Thanks,
Dexuan