Hi Hans,
On 16-Nov-21 19:01, Hans de Goede wrote:
> [CAUTION: External Email]
>
> Hi,
>
> On 10/29/21 19:23, Sanket Goswami wrote:
>> Store the root port information in amd_pmc_probe() so that the
>> information can be used across multiple routines.
>>
>> Signed-off-by: Sanket Goswami <Sanket.Goswami@xxxxxxx>
>> ---
>> Changes in v5:
>> - Remove pci_dev_put() from amd_pmc_remove() as its no longer required.
>>
>> Changes in v4:
>> - No change.
>>
>> Changes in v3:
>> - Add pci_dev_put() in amd_pmc_remove().
>>
>> Changes in v2:
>> - Store the rdev info in amd_pmc_probe() as suggested by Hans.
>>
>> drivers/platform/x86/amd-pmc.c | 2 ++
>> 1 file changed, 2 insertions(+)
>>
>> diff --git a/drivers/platform/x86/amd-pmc.c b/drivers/platform/x86/amd-pmc.c
>> index 9af02860ed59..ea099f7759f2 100644
>> --- a/drivers/platform/x86/amd-pmc.c
>> +++ b/drivers/platform/x86/amd-pmc.c
>> @@ -121,6 +121,7 @@ struct amd_pmc_dev {
>> u16 minor;
>> u16 rev;
>> struct device *dev;
>> + struct pci_dev *rdev;
>> struct mutex lock; /* generic mutex lock */
>> #if IS_ENABLED(CONFIG_DEBUG_FS)
>> struct dentry *dbgfs_dir;
>> @@ -538,6 +539,7 @@ static int amd_pmc_probe(struct platform_device *pdev)
>> }
>>
>> dev->cpu_id = rdev->device;
>> + dev->rdev = rdev;
>> err = pci_write_config_dword(rdev, AMD_PMC_SMU_INDEX_ADDRESS, AMD_PMC_BASE_ADDR_LO);
>> if (err) {
>> dev_err(dev->dev, "error writing to 0x%x\n", AMD_PMC_SMU_INDEX_ADDRESS);
>>
>
>
> I'm afraid this is still not correct:
>
> 1. The pci_dev_put() at line 570 is still there, so after that line
> you no longer have a reference to the pci_dev and the pointer may
> end up pointing to free-ed memory
>
> 2. Once you drop the pci_dev_put() at line 570, all the error-exit
> paths from probe after that, like this one :
>
> dev->regbase = devm_ioremap(dev->dev, base_addr + AMD_PMC_BASE_ADDR_OFFSET,
> AMD_PMC_MAPPING_SIZE);
> if (!dev->regbase)
> return -ENOMEM;
>
> need to be changed to now, put the rdev (since that is now no longer
> done on line 570), so this needs to be changed to:
>
> dev->regbase = devm_ioremap(dev->dev, base_addr + AMD_PMC_BASE_ADDR_OFFSET,
> AMD_PMC_MAPPING_SIZE);
> if (!dev->regbase) {
> err = -ENOMEM;
> goto err_pci_dev_put;
> }
>
> and the same for:
>
> dev->fch_virt_addr = devm_ioremap(dev->dev, fch_phys_addr, FCH_SSC_MAPPING_SIZE);
> if (!dev->fch_virt_addr)
> return -ENOMEM;
>
> 3. Since you now keep the reference on a succesfull probe, you need to add a
>
> pci_dev_put(dev->rdev);
>
> call to amd_pmc_remove()
>
>
> Note that the changelog says you already did 3. in v3 but for some reason you
> have completely dropped that and related changes now again :|
>
> I've already asked for these changes and explained what you needed to do
> several times now; and to be honest this is growing quite tiresome.
Apologies for messing it up. I just sent out v6 for your review. Hope it would address the issues
Thanks,
Sanket
