Hello, On Tuesday, February 21, 2012 10:30 PM Aaro Koskinen wrote: > On Fri, 17 Feb 2012, Marek Szyprowski wrote: > > +/** > > + * dma_release_from_contiguous() - release allocated pages > > + * @dev: Pointer to device for which the pages were allocated. > > + * @pages: Allocated pages. > > + * @count: Number of allocated pages. > > + * > > + * This function releases memory allocated by dma_alloc_from_contiguous(). > > + * It returns false when provided pages do not belong to contiguous area and > > + * true otherwise. > > + */ > > +bool dma_release_from_contiguous(struct device *dev, struct page *pages, > > + int count) > > +{ > > + struct cma *cma = dev_get_cma_area(dev); > > + unsigned long pfn; > > + > > + if (!cma || !pages) > > + return false; > > + > > + pr_debug("%s(page %p)\n", __func__, (void *)pages); > > + > > + pfn = page_to_pfn(pages); > > + > > + if (pfn < cma->base_pfn || pfn >= cma->base_pfn + cma->count) > > + return false; > > + > > + VM_BUG_ON(pfn + count > cma->base_pfn); > > Are you sure the VM_BUG_ON() condition is correct here? Thanks for pointing this bug. '+ cma->count' is missing in the second part. Best regards -- Marek Szyprowski Samsung Poland R&D Center -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>