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Sender: Corey Minyard <tcminyard@gmail.com>
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Date: Fri, 10 Apr 2015 06:47:47 -0500
From: Corey Minyard <minyard@acm.org>
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To: Alistair Popple <alistair@popple.id.au>,
 openipmi-developer@lists.sourceforge.net
Subject: Re: [Openipmi-developer] [PATCH] ipmi/powernv: Fix minor locking bug
References: <1428651140-13665-1-git-send-email-alistair@popple.id.au>
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I should have caught that one.  Thanks.

-corey

On 04/10/2015 02:32 AM, Alistair Popple wrote:
> If ipmi_powernv_recv(...) is called without a current message it
> prints a warning and returns. However it fails to release the message
> lock causing the system to dead lock during any subsequent IPMI
> operations.
>
> This error path should never normally be taken unless there are bugs
> elsewhere in the system.
>
> Signed-off-by: Alistair Popple <alistair@popple.id.au>
> ---
>  drivers/char/ipmi/ipmi_powernv.c | 1 +
>  1 file changed, 1 insertion(+)
>
> diff --git a/drivers/char/ipmi/ipmi_powernv.c b/drivers/char/ipmi/ipmi_powernv.c
> index b3a2224..9b409c0 100644
> --- a/drivers/char/ipmi/ipmi_powernv.c
> +++ b/drivers/char/ipmi/ipmi_powernv.c
> @@ -126,6 +126,7 @@ static int ipmi_powernv_recv(struct ipmi_smi_powernv *smi)
>  	spin_lock_irqsave(&smi->msg_lock, flags);
>  
>  	if (!smi->cur_msg) {
> +		spin_unlock_irqrestore(&smi->msg_lock, flags);
>  		pr_warn("no current message?\n");
>  		return 0;
>  	}