linux-kernel - Re: [PATCH v1 1/2] ata: libahci_platform: Get rid of dup message when IRQ can't be retrieved

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <cf7b4f8b-3423-0cb3-c765-c2903a5f2e4d@opensource.wdc.com>
Date:   Fri, 10 Dec 2021 07:57:48 +0900
From:   Damien Le Moal <damien.lemoal@...nsource.wdc.com>
To:     Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
        linux-ide@...r.kernel.org, linux-kernel@...r.kernel.org
Cc:     Hans de Goede <hdegoede@...hat.com>, Jens Axboe <axboe@...nel.dk>
Subject: Re: [PATCH v1 1/2] ata: libahci_platform: Get rid of dup message when
 IRQ can't be retrieved

On 2021/12/10 7:49, Damien Le Moal wrote:
> On 2021/12/09 23:59, Andy Shevchenko wrote:
>> platform_get_irq() will print a message when it fails.
>> No need to repeat this.
>>
>> While at it, drop redundant check for 0 as platform_get_irq() spills
>> out a big WARN() in such case.
> 
> The reason you should be able to remove the "if (!irq)" test is that
> platform_get_irq() never returns 0. At least, that is what the function kdoc
> says. But looking at platform_get_irq_optional(), which is called by
> platform_get_irq(), the out label is:
> 
> 	WARN(ret == 0, "0 is an invalid IRQ number\n");
> 	return ret;
> 
> So 0 will be returned as-is. That is rather weird. That should be fixed to
> return -ENXIO:
> 
> 	if (WARN(ret == 0, "0 is an invalid IRQ number\n"))
> 		return -ENXIO;
> 	return ret;
> 
> Otherwise, I do not think that removing the "if (!irq)" hunk is safe. no ?

Replying to myself :)
I replied before reading Sergei replies that points this out.

> 
>>
>> Signed-off-by: Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
>> ---
>>  drivers/ata/libahci_platform.c | 7 +------
>>  1 file changed, 1 insertion(+), 6 deletions(-)
>>
>> diff --git a/drivers/ata/libahci_platform.c b/drivers/ata/libahci_platform.c
>> index 0910441321f7..1af642c84e7b 100644
>> --- a/drivers/ata/libahci_platform.c
>> +++ b/drivers/ata/libahci_platform.c
>> @@ -579,13 +579,8 @@ int ahci_platform_init_host(struct platform_device *pdev,
>>  	int i, irq, n_ports, rc;
>>  
>>  	irq = platform_get_irq(pdev, 0);
>> -	if (irq < 0) {
>> -		if (irq != -EPROBE_DEFER)
>> -			dev_err(dev, "no irq\n");
>> +	if (irq < 0)
>>  		return irq;
>> -	}
>> -	if (!irq)
>> -		return -EINVAL;
>>  
>>  	hpriv->irq = irq;
>>  
> 
> 


-- 
Damien Le Moal
Western Digital Research