From 9b6e63cbf85b89b2dbffa4955dbf2df8250e5375 Mon Sep 17 00:00:00 2001
From: Michal Hocko <mhocko@suse.com>
Date: Tue, 3 Oct 2017 16:16:19 -0700
Subject: [PATCH 2/3] mm, page_alloc: add scheduling point to memmap_init_zone
Git-commit: 9b6e63cbf85b89b2dbffa4955dbf2df8250e5375
Patch-mainline: v4.14-rc4
References: bnc#1057079
memmap_init_zone gets a pfn range to initialize and it can be really
large resulting in a soft lockup on non-preemptible kernels
NMI watchdog: BUG: soft lockup - CPU#31 stuck for 23s! [kworker/u642:5:1720]
[...]
task: ffff88ecd7e902c0 ti: ffff88eca4e50000 task.ti: ffff88eca4e50000
RIP: move_pfn_range_to_zone+0x185/0x1d0
[...]
Call Trace:
devm_memremap_pages+0x2c7/0x430
pmem_attach_disk+0x2fd/0x3f0 [nd_pmem]
nvdimm_bus_probe+0x64/0x110 [libnvdimm]
driver_probe_device+0x1f7/0x420
bus_for_each_drv+0x52/0x80
__device_attach+0xb0/0x130
bus_probe_device+0x87/0xa0
device_add+0x3fc/0x5f0
nd_async_device_register+0xe/0x40 [libnvdimm]
async_run_entry_fn+0x43/0x150
process_one_work+0x14e/0x410
worker_thread+0x116/0x490
kthread+0xc7/0xe0
ret_from_fork+0x3f/0x70
Fix this by adding a scheduling point once per page block.
Link: http://lkml.kernel.org/r/20170918121410.24466-3-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reported-by: Johannes Thumshirn <jthumshirn@suse.de>
Tested-by: Johannes Thumshirn <jthumshirn@suse.de>
Cc: Dan Williams <dan.j.williams@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
mm/page_alloc.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 38d165a87860..77e4d3c5c57b 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -5367,6 +5367,7 @@ void __meminit memmap_init_zone(unsigned long size, int nid, unsigned long zone,
__init_single_page(page, pfn, zone, nid);
set_pageblock_migratetype(page, MIGRATE_MOVABLE);
+ cond_resched();
} else {
__init_single_pfn(pfn, zone, nid);
}
--
1.8.5.6