Subject: Re: [PATCH 4/5] kernel handling of memory DLPAR

From: Nathan Fontenot <[email-masked]>
Date: Mon, 14 Sep 2009 13:18:31 -0500

Andrey Panin wrote:
> On 254, 09 11, 2009 at 04:14:35PM -0500, Nathan Fontenot wrote:
>> This adds the capability to DLPAR add and remove memory from the kernel.  The
>> patch extends the powerpc handling of memory_add_physaddr_to_nid(), which is
>> called from the sysfs memory 'probe' file to first ensure that the memory
>> has been added to the system.  This is done by creating a platform specific
>> callout from the routine.  The pseries implementation of this handles the
>> DLPAR work to add the memory to the system and update the device tree.
>>
>> The patch also creates a pseries only 'release' sys file,
>> /sys/devices/system/memory/release.  This file handles the DLPAR
>> release of
>> memory back to firmware and updating of the device-tree.
>>
>> Signed-off-by: Nathan Fontenot <[email-masked]>
> 
>> +static struct property *clone_property(struct property *old_prop)
>> +{
>> +	struct property *new_prop;
>> +
>> +	new_prop = kzalloc((sizeof *new_prop), GFP_KERNEL);
>> +	if (!new_prop)
>> +		return NULL;
>> +
>> +	new_prop->name = kzalloc(strlen(old_prop->name) + 1, GFP_KERNEL);
>> +	new_prop->value = kzalloc(old_prop->length + 1, GFP_KERNEL);
> 
> Memory leak here. What if one kzalloc() succeeded and another failed ?
> 

This should be fine.  The free_property routine will free the name or value
fields if they are allocated.

-Nathan

>> +	if (!new_prop->name || !new_prop->value) {
>> +		free_property(new_prop);
>> +		return NULL;
>> +	}
>> +
>> +	strcpy(new_prop->name, old_prop->name);
>> +	memcpy(new_prop->value, old_prop->value, old_prop->length);
>> +	new_prop->length = old_prop->length;
>> +
>> +	return new_prop;
>> +}