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Date:   Wed, 04 Apr 2018 22:30:13 +0200
Message-ID: <s5hsh8ayasq.wl-tiwai@suse.de>
From:   Takashi Iwai <tiwai@suse.de>
To:     Stuart Hayes <stuart.w.hayes@gmail.com>
Cc:     linux-kernel@vger.kernel.org, Douglas_Warzecha@Dell.com
Subject: Re: [PATCH v3] dell_rbu: make firmware payload memory uncachable
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References: <26829bed-39e5-c35d-8800-7116adaea603@gmail.com>
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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