Re: [PATCH v3 -next 1/9] DMA, CMA: fix possible memory leak
Hi, Joonsoo On Mon, Jun 16, 2014 at 02:40:43PM +0900, Joonsoo Kim wrote: We should free memory for bitmap when we find zone mis-match, otherwise this memory will leak. Additionally, I copy code comment from PPC KVM's CMA code to inform why we need to check zone mis-match. * Note Minchan suggested to add a tag for the stable, but, I don't do it, because I found this possibility during code-review and, IMO, this patch isn't suitable for stable tree. Nice idea to put the comment in here. Thanks Joonsoo. It seems you obey It must fix a real bug that bothers people on Documentation/stable_kernel_rules.txt but it's a really obvious bug and hard to get a report from people because limited user and hard to detect small such small memory leak. In my experince, Andrew perfered stable marking for such a obvious problem but simple fix like this but not sure so let's pass the decision to him and will learn a lesson from him and will follow the decision from now on. Thanks. Acked-by: Minchan Kim minc...@kernel.org Acked-by: Zhang Yanfei zhangyan...@cn.fujitsu.com Reviewed-by: Michal Nazarewicz min...@mina86.com Reviewed-by: Aneesh Kumar K.V aneesh.ku...@linux.vnet.ibm.com Signed-off-by: Joonsoo Kim iamjoonsoo@lge.com diff --git a/drivers/base/dma-contiguous.c b/drivers/base/dma-contiguous.c index 83969f8..6467c91 100644 --- a/drivers/base/dma-contiguous.c +++ b/drivers/base/dma-contiguous.c @@ -176,14 +176,24 @@ static int __init cma_activate_area(struct cma *cma) base_pfn = pfn; for (j = pageblock_nr_pages; j; --j, pfn++) { WARN_ON_ONCE(!pfn_valid(pfn)); + /* + * alloc_contig_range requires the pfn range + * specified to be in the same zone. Make this + * simple by forcing the entire CMA resv range + * to be in the same zone. + */ if (page_zone(pfn_to_page(pfn)) != zone) - return -EINVAL; + goto err; } init_cma_reserved_pageblock(pfn_to_page(base_pfn)); } while (--i); mutex_init(cma-lock); return 0; + +err: + kfree(cma-bitmap); + return -EINVAL; } static struct cma cma_areas[MAX_CMA_AREAS]; -- 1.7.9.5 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majord...@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: a href=mailto:d...@kvack.org; em...@kvack.org /a -- Kind regards, Minchan Kim -- To unsubscribe from this list: send the line unsubscribe kvm in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH v3 -next 1/9] DMA, CMA: fix possible memory leak
On Mon, Jun 16, 2014 at 03:27:19PM +0900, Minchan Kim wrote: Hi, Joonsoo On Mon, Jun 16, 2014 at 02:40:43PM +0900, Joonsoo Kim wrote: We should free memory for bitmap when we find zone mis-match, otherwise this memory will leak. Additionally, I copy code comment from PPC KVM's CMA code to inform why we need to check zone mis-match. * Note Minchan suggested to add a tag for the stable, but, I don't do it, because I found this possibility during code-review and, IMO, this patch isn't suitable for stable tree. Nice idea to put the comment in here. Thanks Joonsoo. It seems you obey It must fix a real bug that bothers people on Documentation/stable_kernel_rules.txt but it's a really obvious bug and hard to get a report from people because limited user and hard to detect small such small memory leak. In my experince, Andrew perfered stable marking for such a obvious problem but simple fix like this but not sure so let's pass the decision to him and will learn a lesson from him and will follow the decision from now on. Yes, I intended to pass the decision to others. :) Thanks. Acked-by: Minchan Kim minc...@kernel.org Thanks. -- To unsubscribe from this list: send the line unsubscribe kvm in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH v3 -next 1/9] DMA, CMA: fix possible memory leak
Hi, Joonsoo On Mon, Jun 16, 2014 at 02:40:43PM +0900, Joonsoo Kim wrote: We should free memory for bitmap when we find zone mis-match, otherwise this memory will leak. Additionally, I copy code comment from PPC KVM's CMA code to inform why we need to check zone mis-match. * Note Minchan suggested to add a tag for the stable, but, I don't do it, because I found this possibility during code-review and, IMO, this patch isn't suitable for stable tree. Nice idea to put the comment in here. Thanks Joonsoo. It seems you obey It must fix a real bug that bothers people on Documentation/stable_kernel_rules.txt but it's a really obvious bug and hard to get a report from people because limited user and hard to detect small such small memory leak. In my experince, Andrew perfered stable marking for such a obvious problem but simple fix like this but not sure so let's pass the decision to him and will learn a lesson from him and will follow the decision from now on. Thanks. Acked-by: Minchan Kim minc...@kernel.org Acked-by: Zhang Yanfei zhangyan...@cn.fujitsu.com Reviewed-by: Michal Nazarewicz min...@mina86.com Reviewed-by: Aneesh Kumar K.V aneesh.ku...@linux.vnet.ibm.com Signed-off-by: Joonsoo Kim iamjoonsoo@lge.com diff --git a/drivers/base/dma-contiguous.c b/drivers/base/dma-contiguous.c index 83969f8..6467c91 100644 --- a/drivers/base/dma-contiguous.c +++ b/drivers/base/dma-contiguous.c @@ -176,14 +176,24 @@ static int __init cma_activate_area(struct cma *cma) base_pfn = pfn; for (j = pageblock_nr_pages; j; --j, pfn++) { WARN_ON_ONCE(!pfn_valid(pfn)); + /* + * alloc_contig_range requires the pfn range + * specified to be in the same zone. Make this + * simple by forcing the entire CMA resv range + * to be in the same zone. + */ if (page_zone(pfn_to_page(pfn)) != zone) - return -EINVAL; + goto err; } init_cma_reserved_pageblock(pfn_to_page(base_pfn)); } while (--i); mutex_init(cma-lock); return 0; + +err: + kfree(cma-bitmap); + return -EINVAL; } static struct cma cma_areas[MAX_CMA_AREAS]; -- 1.7.9.5 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majord...@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: a href=mailto:d...@kvack.org; em...@kvack.org /a -- Kind regards, Minchan Kim -- To unsubscribe from this list: send the line unsubscribe kvm-ppc in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH v3 -next 1/9] DMA, CMA: fix possible memory leak
On Mon, Jun 16, 2014 at 03:27:19PM +0900, Minchan Kim wrote: Hi, Joonsoo On Mon, Jun 16, 2014 at 02:40:43PM +0900, Joonsoo Kim wrote: We should free memory for bitmap when we find zone mis-match, otherwise this memory will leak. Additionally, I copy code comment from PPC KVM's CMA code to inform why we need to check zone mis-match. * Note Minchan suggested to add a tag for the stable, but, I don't do it, because I found this possibility during code-review and, IMO, this patch isn't suitable for stable tree. Nice idea to put the comment in here. Thanks Joonsoo. It seems you obey It must fix a real bug that bothers people on Documentation/stable_kernel_rules.txt but it's a really obvious bug and hard to get a report from people because limited user and hard to detect small such small memory leak. In my experince, Andrew perfered stable marking for such a obvious problem but simple fix like this but not sure so let's pass the decision to him and will learn a lesson from him and will follow the decision from now on. Yes, I intended to pass the decision to others. :) Thanks. Acked-by: Minchan Kim minc...@kernel.org Thanks. -- To unsubscribe from this list: send the line unsubscribe kvm-ppc in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html