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Message-ID: <d84fe574-e6cc-ad77-a44c-1eb8df3f2b6b@alu.unizg.hr>
Date:   Tue, 28 Mar 2023 00:25:38 +0200
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Subject: Re: [PATCH] xhci: Free the command allocated for setting LPM if we
 return early
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To:     Mathias Nyman <mathias.nyman@linux.intel.com>,
        linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org
Cc:     gregkh@linuxfoundation.org, ubuntu-devel-discuss@lists.ubuntu.com,
        stern@rowland.harvard.edu, arnd@arndb.de, Stable@vger.kernel.org
References: <b86fcdbd-f1c6-846f-838f-b7679ec4e2b4@linux.intel.com>
 <20230327095019.1017159-1-mathias.nyman@linux.intel.com>
From:   Mirsad Goran Todorovac <mirsad.todorovac@alu.unizg.hr>
In-Reply-To: <20230327095019.1017159-1-mathias.nyman@linux.intel.com>
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On 27. 03. 2023. 11:50, Mathias Nyman wrote:
> The command allocated to set exit latency LPM values need to be freed in
> case the command is never queued. This would be the case if there is no
> change in exit latency values, or device is missing.
> 
> Fixes: 5c2a380a5aa8 ("xhci: Allocate separate command structures for each LPM command")
> Cc: <Stable@vger.kernel.org>
> Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
> ---
>  drivers/usb/host/xhci.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
> index bdb6dd819a3b..6307bae9cddf 100644
> --- a/drivers/usb/host/xhci.c
> +++ b/drivers/usb/host/xhci.c
> @@ -4442,6 +4442,7 @@ static int __maybe_unused xhci_change_max_exit_latency(struct xhci_hcd *xhci,
>  
>  	if (!virt_dev || max_exit_latency == virt_dev->current_mel) {
>  		spin_unlock_irqrestore(&xhci->lock, flags);
> +		xhci_free_command(xhci, command);
>  		return 0;
>  	}
>  

After more testing, I can confirm that your patch fixes the leak in the original
environment.

And I see that you independently already have bisected the culprit commit, so I
have needlessly duplicated the work.

However, I consider myself still a learner and an absolute beginner in the Linux
kernel world ...

Best regards,
Mirsad

-- 
Mirsad Goran Todorovac
Sistem inženjer
Grafički fakultet | Akademija likovnih umjetnosti
Sveučilište u Zagrebu
 
System engineer
Faculty of Graphic Arts | Academy of Fine Arts
University of Zagreb, Republic of Croatia
The European Union

"I see something approaching fast ... Will it be friends with me?"