On Fri, Nov 18, 2011 at 8:43 AM, Marek Szyprowski <m.szyprowski@xxxxxxxxxxx> wrote: > Welcome everyone once again, > Please notice that this patch series is aimed to start further > discussion. There are still few issues that need to be resolved before > CMA will be really ready. The most hot problem is the issue with movable > pages that causes migration to fail from time to time. Our investigation > leads us to the point that these rare pages cannot be migrated because > there are some pending io operations on them. I am running a simple test to allocate contiguous regions and write a log on in a file on sdcard simultaneously. I can reproduce this migration failure 100% times with it. when I tracked the pages that failed to migrate, I found them on the buffer head lru list with a reference held on the buffer_head in the page, which causes drop_buffers() to fail. So, i guess my question is, until all the migration failures are tracked down and fixed, is there a plan to retry the contiguous allocation from a new range in the CMA region? ~ sandeep -- 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>