2020-10-30 01:30:46

by Qinglang Miao

Subject: [PATCH] PCI: v3: fix missing clk_disable_unprepare() on error in v3_pci_probe

Fix the missing clk_disable_unprepare() before return
from v3_pci_probe() in the error handling case.

Signed-off-by: Qinglang Miao <[email protected]>
---
drivers/pci/controller/pci-v3-semi.c | 14 +++++++++++---
1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/drivers/pci/controller/pci-v3-semi.c b/drivers/pci/controller/pci-v3-semi.c
index 154a53986..e24abc5b4 100644
--- a/drivers/pci/controller/pci-v3-semi.c
+++ b/drivers/pci/controller/pci-v3-semi.c
@@ -739,8 +739,10 @@ static int v3_pci_probe(struct platform_device *pdev)

regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
v3->base = devm_ioremap_resource(dev, regs);
- if (IS_ERR(v3->base))
+ if (IS_ERR(v3->base)) {
+ clk_disable_unprepare(clk);
return PTR_ERR(v3->base);
+ }
/*
* The hardware has a register with the physical base address
* of the V3 controller itself, verify that this is the same
@@ -754,17 +756,22 @@ static int v3_pci_probe(struct platform_device *pdev)
regs = platform_get_resource(pdev, IORESOURCE_MEM, 1);
if (resource_size(regs) != SZ_16M) {
dev_err(dev, "config mem is not 16MB!\n");
+ clk_disable_unprepare(clk);
return -EINVAL;
}
v3->config_mem = regs->start;
v3->config_base = devm_ioremap_resource(dev, regs);
- if (IS_ERR(v3->config_base))
+ if (IS_ERR(v3->config_base)) {
+ clk_disable_unprepare(clk);
return PTR_ERR(v3->config_base);
+ }

/* Get and request error IRQ resource */
irq = platform_get_irq(pdev, 0);
- if (irq < 0)
+ if (irq < 0) {
+ clk_disable_unprepare(clk);
return irq;
+ }

ret = devm_request_irq(dev, irq, v3_irq, 0,
"PCIv3 error", v3);
@@ -772,6 +779,7 @@ static int v3_pci_probe(struct platform_device *pdev)
dev_err(dev,
"unable to request PCIv3 error IRQ %d (%d)\n",
irq, ret);
+ clk_disable_unprepare(clk);
return ret;
}

--
2.23.0

2020-11-02 13:50:06

by Rob Herring (Arm)

Subject: Re: [PATCH] PCI: v3: fix missing clk_disable_unprepare() on error in v3_pci_probe

On Thu, Oct 29, 2020 at 8:28 PM Qinglang Miao <[email protected]> wrote:
>
> Fix the missing clk_disable_unprepare() before return
> from v3_pci_probe() in the error handling case.
>
> Signed-off-by: Qinglang Miao <[email protected]>
> ---
> drivers/pci/controller/pci-v3-semi.c | 14 +++++++++++---
> 1 file changed, 11 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/pci/controller/pci-v3-semi.c b/drivers/pci/controller/pci-v3-semi.c
> index 154a53986..e24abc5b4 100644
> --- a/drivers/pci/controller/pci-v3-semi.c
> +++ b/drivers/pci/controller/pci-v3-semi.c
> @@ -739,8 +739,10 @@ static int v3_pci_probe(struct platform_device *pdev)
>
> regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> v3->base = devm_ioremap_resource(dev, regs);
> - if (IS_ERR(v3->base))
> + if (IS_ERR(v3->base)) {
> + clk_disable_unprepare(clk);

You can reorder things moving the clock enable later (after mapping
resources, but before devm_request_irq) and avoid some of these. Also
move this check down:

if (readl(v3->base + V3_LB_IO_BASE) != (regs->start >> 16))


> return PTR_ERR(v3->base);
> + }
> /*
> * The hardware has a register with the physical base address
> * of the V3 controller itself, verify that this is the same
> @@ -754,17 +756,22 @@ static int v3_pci_probe(struct platform_device *pdev)
> regs = platform_get_resource(pdev, IORESOURCE_MEM, 1);
> if (resource_size(regs) != SZ_16M) {
> dev_err(dev, "config mem is not 16MB!\n");
> + clk_disable_unprepare(clk);
> return -EINVAL;
> }
> v3->config_mem = regs->start;
> v3->config_base = devm_ioremap_resource(dev, regs);
> - if (IS_ERR(v3->config_base))
> + if (IS_ERR(v3->config_base)) {
> + clk_disable_unprepare(clk);
> return PTR_ERR(v3->config_base);
> + }
>
> /* Get and request error IRQ resource */
> irq = platform_get_irq(pdev, 0);
> - if (irq < 0)
> + if (irq < 0) {
> + clk_disable_unprepare(clk);
> return irq;
> + }
>
> ret = devm_request_irq(dev, irq, v3_irq, 0,
> "PCIv3 error", v3);
> @@ -772,6 +779,7 @@ static int v3_pci_probe(struct platform_device *pdev)
> dev_err(dev,
> "unable to request PCIv3 error IRQ %d (%d)\n",
> irq, ret);
> + clk_disable_unprepare(clk);
> return ret;

You still leave the clock enabled if pci_host_probe() fails.

Rob

2020-11-03 07:29:49

by Qinglang Miao

Subject: Re: [PATCH] PCI: v3: fix missing clk_disable_unprepare() on error in v3_pci_probe

在 2020/11/2 21:48, Rob Herring 写道:
> On Thu, Oct 29, 2020 at 8:28 PM Qinglang Miao <[email protected]> wrote:
>>
>> Fix the missing clk_disable_unprepare() before return
>> from v3_pci_probe() in the error handling case.
>>
>> Signed-off-by: Qinglang Miao <[email protected]>
>> ---
>> drivers/pci/controller/pci-v3-semi.c | 14 +++++++++++---
>> 1 file changed, 11 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/pci/controller/pci-v3-semi.c b/drivers/pci/controller/pci-v3-semi.c
>> index 154a53986..e24abc5b4 100644
>> --- a/drivers/pci/controller/pci-v3-semi.c
>> +++ b/drivers/pci/controller/pci-v3-semi.c
>> @@ -739,8 +739,10 @@ static int v3_pci_probe(struct platform_device *pdev)
>>
>> regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>> v3->base = devm_ioremap_resource(dev, regs);
>> - if (IS_ERR(v3->base))
>> + if (IS_ERR(v3->base)) {
>> + clk_disable_unprepare(clk);
>
> You can reorder things moving the clock enable later (after mapping
> resources, but before devm_request_irq) and avoid some of these. Also
> move this check down:
>
> if (readl(v3->base + V3_LB_IO_BASE) != (regs->start >> 16))
>
Hi Rob,

I've sent a new patch which reorder things and cover all error branches.

But I'm not sure why and where should I move this check down:
if (readl(v3->base + V3_LB_IO_BASE) != (regs->start >> 16)). So I
didn't move it in current version.

If you think it's still necessary, please let me know.

Thanks.
>
>> return PTR_ERR(v3->base);
>> + }
>> /*
>> * The hardware has a register with the physical base address
>> * of the V3 controller itself, verify that this is the same
>> @@ -754,17 +756,22 @@ static int v3_pci_probe(struct platform_device *pdev)
>> regs = platform_get_resource(pdev, IORESOURCE_MEM, 1);
>> if (resource_size(regs) != SZ_16M) {
>> dev_err(dev, "config mem is not 16MB!\n");
>> + clk_disable_unprepare(clk);
>> return -EINVAL;
>> }
>> v3->config_mem = regs->start;
>> v3->config_base = devm_ioremap_resource(dev, regs);
>> - if (IS_ERR(v3->config_base))
>> + if (IS_ERR(v3->config_base)) {
>> + clk_disable_unprepare(clk);
>> return PTR_ERR(v3->config_base);
>> + }
>>
>> /* Get and request error IRQ resource */
>> irq = platform_get_irq(pdev, 0);
>> - if (irq < 0)
>> + if (irq < 0) {
>> + clk_disable_unprepare(clk);
>> return irq;
>> + }
>>
>> ret = devm_request_irq(dev, irq, v3_irq, 0,
>> "PCIv3 error", v3);
>> @@ -772,6 +779,7 @@ static int v3_pci_probe(struct platform_device *pdev)
>> dev_err(dev,
>> "unable to request PCIv3 error IRQ %d (%d)\n",
>> irq, ret);
>> + clk_disable_unprepare(clk);
>> return ret;
>
> You still leave the clock enabled if pci_host_probe() fails.
>
> Rob
> .
>