Re: [Bug fix PATCH v4] Reusing a resource structure allocated by bootmem

[Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>]

2013/04/18 22:42, Johannes Weiner wrote:
> On Thu, Apr 18, 2013 at 05:36:12PM +0900, Yasuaki Ishimatsu wrote:
>> @@ -151,6 +162,39 @@ __initcall(ioresources_init);
>>
>>   #endif /* CONFIG_PROC_FS */
>>
>> +static void free_resource(struct resource *res)
>> +{
>> +	if (!res)
>> +		return;
>> +
>> +	if (PageSlab(virt_to_head_page(res))) {
>> +		spin_lock(&bootmem_resource_lock);
>> +		res->sibling = bootmem_resource.sibling;
>> +		bootmem_resource.sibling = res;
>> +		spin_unlock(&bootmem_resource_lock);
>> +	} else {
>> +		kfree(res);
>> +	}
>

> The branch is mixed up, you are collecting slab objects in
> bootmem_resource and kfreeing bootmem.

Ah. I'm wrong. I'll update soon.

Thanks,
Yasuaki Ishimatsu

>
>> +static struct resource *get_resource(gfp_t flags)
>> +{
>> +	struct resource *res = NULL;
>> +
>> +	spin_lock(&bootmem_resource_lock);
>> +	if (bootmem_resource.sibling) {
>> +		res = bootmem_resource.sibling;
>> +		bootmem_resource.sibling = res->sibling;
>> +		memset(res, 0, sizeof(struct resource));
>> +	}
>> +	spin_unlock(&bootmem_resource_lock);
>> +
>> +	if (!res)
>> +		res = kzalloc(sizeof(struct resource), flags);
>> +
>> +	return res;
>> +}
>> +
>>   /* Return the conflict entry if you can't request it */
>>   static struct resource * __request_resource(struct resource *root, struct resource *new)
>>   {


--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>