On Fri, Aug 05, 2016 at 01:17:04PM +0100, James Hogan wrote:
> The recent commit 599d0c954f91 ("mm, vmscan: move LRU lists to node"),
> changed memory management code so that show_mem() is no longer safe to
> call prior to setup_per_cpu_pageset(), as pgdat->per_cpu_nodestats will
> still be NULL. This causes an oops on metag due to the call to
> show_mem() from mem_init():
>
> node_page_state_snapshot(...) + 0x48
> pgdat_reclaimable(struct pglist_data * pgdat = 0x402517a0)
> show_free_areas(unsigned int filter = 0) + 0x2cc
> show_mem(unsigned int filter = 0) + 0x18
> mem_init()
> mm_init()
> start_kernel() + 0x204
>
> This wasn't a problem before with zone_reclaimable() as zone_pcp_init()
> was already setting zone->pageset to &boot_pageset, via setup_arch() and
> paging_init(), which happens before mm_init():
>
> zone_pcp_init(...)
> free_area_init_core(...) + 0x138
> free_area_init_node(int nid = 0, ...) + 0x1a0
> free_area_init_nodes(...) + 0x440
> paging_init(unsigned long mem_end = 0x4fe00000) + 0x378
> setup_arch(char ** cmdline_p = 0x4024e038) + 0x2b8
> start_kernel() + 0x54
>
> No other arches appear to call show_mem() during boot, and it doesn't
> really add much value to the log, so lets just drop it from mem_init().
>
> Signed-off-by: James Hogan <james.hogan@xxxxxxxxxx>
> Cc: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>
Acked-by: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>
--
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/ .
Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>