Commit e35ef639 authored Jul 10, 2017 by Anshuman Khandual Committed by Linus Torvalds Jul 10, 2017

mm/cma.c: warn if the CMA area could not be activated

While activating a CMA area we check to make sure that all the PFNs in
the range are inside the same zone.  This is a requirement for
alloc_contig_range() to work.  Any CMA area failing the check is
disabled for good.  This happens silently right now making all future
cma_alloc() allocations failure inevitable.

Here we add an error message stating that the CMA area could not be
activated which makes it easier to explain any future cma_alloc()
failures on it.  While in there, change the bail out goto label from
'err' to 'not_in_zone' which makes more sense.

Link: http://lkml.kernel.org/r/20170605023729.26303-1-khandual@linux.vnet.ibm.com


Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent 78c72746

mm/cma.c

+3 −2

Original line number	Diff line number	Diff line
		@@ -127,7 +127,7 @@ static int __init cma_activate_area(struct cma *cma)
		* to be in the same zone.
		*/
		if (page_zone(pfn_to_page(pfn)) != zone)
		goto err;
		goto not_in_zone;
		}
		init_cma_reserved_pageblock(pfn_to_page(base_pfn));
		} while (--i);
		@@ -141,7 +141,8 @@ static int __init cma_activate_area(struct cma *cma)

		return 0;

		err:
		not_in_zone:
		pr_err("CMA area %s could not be activated\n", cma->name);
		kfree(cma->bitmap);
		cma->count = 0;
		return -EINVAL;

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