Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > linux.kernel > #1212791

Re: [PATCH] dma/ipu: change ipu_irq_handler() to remove compile warning

From yalin wang <yalin.wang2010@gmail.com>
Newsgroups linux.kernel
Subject Re: [PATCH] dma/ipu: change ipu_irq_handler() to remove compile warning
Date 2015-08-25 10:20 +0200
Message-ID <q1hCy-P0-21@gated-at.bofh.it> (permalink)
References <q1hCy-P0-17@gated-at.bofh.it> <q1hCx-P0-15@gated-at.bofh.it>
Organization linux.* mail to news gateway

Show all headers | View raw


> On Aug 25, 2015, at 16:07, Thomas Gleixner <tglx@linutronix.de> wrote:
> 
> On Tue, 25 Aug 2015, yalin wang wrote:
>> Change ipu_irq_handler() to avoid gcc warning:
>> 
>> drivers/dma/ipu/ipu_irq.c:305:4: warning: 'irq' may be used
>> uninitialized in this function [-Wmaybe-uninitialized]
>>    generic_handle_irq(irq);
> 
> That's a false positive from GCC. irq is always initialized when
> generic_handle_irq() is called.
> 
>> Signed-off-by: yalin wang <yalin.wang2010@gmail.com>
>> ---
>> drivers/dma/ipu/ipu_irq.c | 6 ++----
>> 1 file changed, 2 insertions(+), 4 deletions(-)
>> 
>> diff --git a/drivers/dma/ipu/ipu_irq.c b/drivers/dma/ipu/ipu_irq.c
>> index 7489d2a..1a74eee 100644
>> --- a/drivers/dma/ipu/ipu_irq.c
>> +++ b/drivers/dma/ipu/ipu_irq.c
>> @@ -286,23 +286,21 @@ static void ipu_irq_handler(unsigned int __irq, struct irq_desc *desc)
>> 		raw_spin_unlock(&bank_lock);
>> 		while ((line = ffs(status))) {
>> 			struct ipu_irq_map *map;
>> -			unsigned int irq;
>> 
>> 			line--;
>> 			status &= ~(1UL << line);
>> 
>> 			raw_spin_lock(&bank_lock);
>> 			map = src2map(32 * i + line);
>> -			if (map)
>> -				irq = map->irq;
>> 			raw_spin_unlock(&bank_lock);
>> 
>> 			if (!map) {
>> 				pr_err("IPU: Interrupt on unmapped source %u bank %d\n",
>> 				       line, i);
>> 				continue;
>> +			} else {
>> +				generic_handle_irq(map->irq);
> 
> So you change that from retrieving the irq number with bank lock held
> to an unprotected access.

i see,
i will send a V2 patch .

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Back to linux.kernel | Previous | Next — Previous in thread | Find similar | Unroll thread


Thread

Re: [PATCH] dma/ipu: change ipu_irq_handler() to remove compile  warning Thomas Gleixner <tglx@linutronix.de> - 2015-08-25 10:20 +0200
  Re: [PATCH] dma/ipu: change ipu_irq_handler() to remove compile warning yalin wang <yalin.wang2010@gmail.com> - 2015-08-25 10:20 +0200

csiph-web