On Mon, Jan 30, 2012 at 01:42:50PM +0100, Michal Nazarewicz wrote: > >On Thu, Jan 26, 2012 at 10:00:45AM +0100, Marek Szyprowski wrote: > >>From: Michal Nazarewicz <mina86@xxxxxxxxxx> > >>@@ -313,7 +316,7 @@ static isolate_migrate_t isolate_migratepages(struct zone *zone, > >> } else if (!locked) > >> spin_lock_irq(&zone->lru_lock); > >> > >>- if (!pfn_valid_within(low_pfn)) > >>+ if (!pfn_valid(low_pfn)) > >> continue; > >> nr_scanned++; > >> > > On Mon, 30 Jan 2012 12:24:28 +0100, Mel Gorman <mel@xxxxxxxxx> wrote: > >This chunk looks unrelated to the rest of the patch. > > > >I think what you are doing is patching around a bug that CMA exposed > >which is very similar to the bug report at > >http://www.spinics.net/lists/linux-mm/msg29260.html . Is this true? > > > >If so, I posted a fix that only calls pfn_valid() when necessary. Can > >you check if that works for you and if so, drop this hunk please? If > >the patch does not work for you, then this hunk still needs to be > >in a separate patch and handled separately as it would also be a fix > >for -stable. > > I'll actually never encountered this bug myself and CMA is unlikely to > expose it, since it always operates on continuous memory regions with > no holes. > > I've made this change because looking at the code it seemed like this > may cause problems in some cases. The crash that you linked to looks > like the kind of problem I was thinking about. > > I'll drop this hunk and let you resolve this independently of CMA. > Ok, thanks. -- Mel Gorman SUSE Labs -- 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>