Subject: Re: [PATCH -next] scsi: efct: don't use GFP_KERNEL under spin lock
To:     Maurizio Lombardi <mlombard@redhat.com>
CC:     <linux-kernel@vger.kernel.org>, <target-devel@vger.kernel.org>,
        <linux-scsi@vger.kernel.org>, <hch@lst.de>,
        <james.smart@broadcom.com>, <martin.petersen@oracle.com>
References: <20220110111838.965480-1-yangyingliang@huawei.com>
 <20220110111921.GA91632@raketa>
From:   Yang Yingliang <yangyingliang@huawei.com>
Message-ID: <ee058886-5bf0-db3e-7d78-8bc34bfd2440@huawei.com>
Date:   Mon, 10 Jan 2022 20:10:41 +0800
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Hi,

On 2022/1/10 19:19, Maurizio Lombardi wrote:
> On Mon, Jan 10, 2022 at 07:18:38PM +0800, Yang Yingliang wrote:
>> +	spin_lock_irqsave(&node->els_ios_lock, flags);
>> +
>>   	if (els) {
>>   		/* initialize fields */
>>   		els->els_retries_remaining = EFC_FC_ELS_DEFAULT_RETRIES;
> If the els pointer is NULL you will lock the spinlock and disable the interrupts
> for no reason, maybe you can just protect the list_add_tail()?
>
> +spin_lock_irqsave(&node->els_ios_lock, flags);
>   list_add_tail(&els->list_entry, &node->els_ios_list);
> +spin_unlock_irqrestore(&node->els_ios_lock, flags);
Yes, it's better, I will send a v2 later.

Thanks,
Yang
>
> Maurizio
>
> .