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Subject: Re: [PATCH v3] dell_rbu: make firmware payload memory uncachable
To:     Takashi Iwai <tiwai@suse.de>
Cc:     linux-kernel@vger.kernel.org, Douglas_Warzecha@Dell.com
References: <26829bed-39e5-c35d-8800-7116adaea603@gmail.com>
 <s5hsh8ayasq.wl-tiwai@suse.de>
From:   Stuart Hayes <stuart.w.hayes@gmail.com>
Message-ID: <e94e085f-6b66-5a2f-9654-0ba47d13249b@gmail.com>
Date:   Fri, 6 Apr 2018 08:02:56 -0500
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On 4/4/2018 3:30 PM, Takashi Iwai wrote:
> On Wed, 28 Mar 2018 17:07:47 +0200,
> Stuart Hayes wrote:
>>
>> @@ -180,6 +181,12 @@ static int create_packet(void *data, size_t length)
>>  			invalid_addr_packet_array[idx++] = packet_data_temp_buf;
>>  			packet_data_temp_buf = NULL;
>>  		}
>> +		/*
>> +		 * set to uncachable or it may never get written back before
>> +		 * reboot
>> +		 */
>> +		set_memory_uc((unsigned long)packet_data_temp_buf,
>> +			1 << ordernum);
> 
> Won't this cause Oops when the if-condition above meets?
> Namely packet_data_temp_buf is set to NULL there.
> 
> Maybe better to try a fault injection to check the error handling.
> 
> 
> thanks,
> 
> Takashi
> 

Yes, thank you for catching my mistake.
Stuart