On Mon, Feb 19, 2024 at 07:25:38PM -0800, Andrew Morton wrote: > From: Byungchul Park <byungchul@xxxxxx> > Subject: mm/vmscan: fix a bug calling wakeup_kswapd() with a wrong zone index > Date: Fri, 16 Feb 2024 20:15:02 +0900 > > With numa balancing on, when a numa system is running where a numa node > doesn't have its local memory so it has no managed zones, the following > oops has been observed. It's because wakeup_kswapd() is called with a > wrong zone index, -1. Fixed it by checking the index before calling > wakeup_kswapd(). ... ... > > Link: https://lkml.kernel.org/r/20240216111502.79759-1-byungchul@xxxxxx > Signed-off-by: Byungchul Park <byungchul@xxxxxx> > Reported-by: Hyeongtak Ji <hyeongtak.ji@xxxxxx> > Fixes: c574bbe917036 ("NUMA balancing: optimize page placement for memory tiering system") > Cc: Baolin Wang <baolin.wang@xxxxxxxxxxxxxxxxx> > Cc: "Huang, Ying" <ying.huang@xxxxxxxxx> > Cc: Johannes Weiner <hannes@xxxxxxxxxxx> > Cc: Oscar Salvador <osalvador@xxxxxxx> > Cc: <stable@xxxxxxxxxxxxxxx> > Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> It's a shame that N_MEMORY can actually have no memory (e.g: memmap consuming all zone's memory), but here we are: Reviewed-by: Oscar Salvador <osalvador@xxxxxxx> -- Oscar Salvador SUSE Labs
