[PATCH] drivers/clocksource/qcom: Add missing iounmap() on error when reading clock frequency.

[PATCH] drivers/clocksource/qcom: Add missing iounmap() on error when reading clock frequency.

[Ankit Agrawal]

Add the missing iounmap() when clock frequency fails to get read by the
of_property_read_u32() call.

Signed-off-by: Ankit Agrawal <agrawal.ag.ankit@gmail.com>
---
 drivers/clocksource/timer-qcom.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/clocksource/timer-qcom.c b/drivers/clocksource/timer-qcom.c
index b4afe3a67..a66fa7f8e 100644
--- a/drivers/clocksource/timer-qcom.c
+++ b/drivers/clocksource/timer-qcom.c
@@ -233,6 +233,7 @@ static int __init msm_dt_timer_init(struct device_node *np)
 	}
 
 	if (of_property_read_u32(np, "clock-frequency", &freq)) {
+		iounmap(cpu0_base);
 		pr_err("Unknown frequency\n");
 		return -EINVAL;
 	}
-- 
2.25.1

Re: [PATCH] drivers/clocksource/qcom: Add missing iounmap() on error when reading clock frequency.

[Konrad Dybcio]

On 10.07.2024 1:08 PM, Ankit Agrawal wrote:
> Add the missing iounmap() when clock frequency fails to get read by the
> of_property_read_u32() call.
> 
> Signed-off-by: Ankit Agrawal <agrawal.ag.ankit@gmail.com>
> ---

Or even better, you can extract:

drivers/platform/x86/intel/pmc/core_ssram.c
32:DEFINE_FREE(pmc_core_iounmap, void __iomem *, iounmap(_T));

into a common header, call it something less intel-specific and use
it with __free() here

Konrad

Re: [PATCH] drivers/clocksource/qcom: Add missing iounmap() on error when reading clock frequency.

[Ankit Agrawal]

On Wed, Jul 10, 2024 at 01:54:01PM +0200, Konrad Dybcio wrote:
> On 10.07.2024 1:08 PM, Ankit Agrawal wrote:
> > Add the missing iounmap() when clock frequency fails to get read by the
> > of_property_read_u32() call.
> > 
> > Signed-off-by: Ankit Agrawal <agrawal.ag.ankit@gmail.com>
> > ---
> 
> Or even better, you can extract:
> 
> drivers/platform/x86/intel/pmc/core_ssram.c
> 32:DEFINE_FREE(pmc_core_iounmap, void __iomem *, iounmap(_T));
> 
> into a common header, call it something less intel-specific and use
> it with __free() here

Can you please give a place where adding it would be appropriate? I am
new to contributing here, so any guidance on where to add the
DEFINE_FREE would be really helpful!

Also, just trying to think out loud. Will the cpu0_base pointer (and
also the source_base pointer) be required once this function exits? If
so, I think I will also need to use no_free_ptr() to ensure that the
memory doesn't get iounmap-ed once the function exits.

Thanks!
Ankit

Re: [PATCH] drivers/clocksource/qcom: Add missing iounmap() on error when reading clock frequency.

[Konrad Dybcio]

On 11.07.2024 7:49 AM, Ankit Agrawal wrote:
> On Wed, Jul 10, 2024 at 01:54:01PM +0200, Konrad Dybcio wrote:
>> On 10.07.2024 1:08 PM, Ankit Agrawal wrote:
>>> Add the missing iounmap() when clock frequency fails to get read by the
>>> of_property_read_u32() call.
>>>
>>> Signed-off-by: Ankit Agrawal <agrawal.ag.ankit@gmail.com>
>>> ---
>>
>> Or even better, you can extract:
>>
>> drivers/platform/x86/intel/pmc/core_ssram.c
>> 32:DEFINE_FREE(pmc_core_iounmap, void __iomem *, iounmap(_T));
>>
>> into a common header, call it something less intel-specific and use
>> it with __free() here
> 
> Can you please give a place where adding it would be appropriate? I am
> new to contributing here, so any guidance on where to add the
> DEFINE_FREE would be really helpful!

I'd say include/linux/io.h sounds alright, but worst case scenario the
maintainer of that file will ask you to move it somewhere else

> Also, just trying to think out loud. Will the cpu0_base pointer (and
> also the source_base pointer) be required once this function exits? If
> so, I think I will also need to use no_free_ptr() to ensure that the
> memory doesn't get iounmap-ed once the function exits.

Ohh right source_base is a global variable.. perhaps the original patch
here makes more sense given we definitely don't wanna unmap that..

So I'd say let's go with this one after all

Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>

Konrad

Re: [PATCH] drivers/clocksource/qcom: Add missing iounmap() on error when reading clock frequency.

[Konrad Dybcio]

On 11.07.2024 10:11 AM, Konrad Dybcio wrote:
> On 11.07.2024 7:49 AM, Ankit Agrawal wrote:
>> On Wed, Jul 10, 2024 at 01:54:01PM +0200, Konrad Dybcio wrote:
>>> On 10.07.2024 1:08 PM, Ankit Agrawal wrote:

[...]

> 
> Ohh right source_base is a global variable.. perhaps the original patch
> here makes more sense given we definitely don't wanna unmap that..
> 
> So I'd say let's go with this one after all
> 
> Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>

We should probably also check if msm_timer_init() succeeds and unmap
if that fails.. we can just check the return value of that function
and if it's non-zero, call iounmap

Konrad

Re: [PATCH] drivers/clocksource/qcom: Add missing iounmap() on error when reading clock frequency.

[Ankit Agrawal]

On Thu, Jul 11, 2024 at 10:13:38AM +0200, Konrad Dybcio wrote:
> On 11.07.2024 10:11 AM, Konrad Dybcio wrote:
> > On 11.07.2024 7:49 AM, Ankit Agrawal wrote:
> >> On Wed, Jul 10, 2024 at 01:54:01PM +0200, Konrad Dybcio wrote:
> >>> On 10.07.2024 1:08 PM, Ankit Agrawal wrote:

[...]

> 
> We should probably also check if msm_timer_init() succeeds and unmap
> if that fails.. we can just check the return value of that function
> and if it's non-zero, call iounmap

Sure. I have updated the patch accordingly. Please find version 2 of the
patch here: https://lore.kernel.org/linux-arm-msm/20240712082747.GA182658@bnew-VirtualBox/

Thanks!
Ankit