在 2021/6/28 上午9:07, zhanglianjie 写道:
On 2021-06-25 21:39, Thomas Bogendoerfer wrote:
On Thu, Jun 24, 2021 at 11:22:12AM +0800, zhanglianjie wrote:
The cause of the problem is as follows:
1. when cat /sys/devices/system/memory/memory0/valid_zones,
test_pages_in_a_zone() will be called.
2. test_pages_in_a_zone() finds the zone according to stat_pfn = 0.
The smallest pfn of the numa node in the mips architecture is 128,
and the page corresponding to the previous 0~127 pfn is not
initialized (page->flags is 0xFFFFFFFF)
3. The nid and zonenum obtained using page_zone(pfn_to_page(0)) are out
of bounds in the corresponding array,
&NODE_DATA(page_to_nid(page))->node_zones[page_zonenum(page)],
access to the out-of-bounds zone member variables appear abnormal,
resulting in Oops.
Therefore, it is necessary to keep the page between 0 and the minimum
pfn to prevent Oops from appearing.
Signed-off-by: zhanglianjie <zhanglianjie@xxxxxxxxxxxxx>
---
arch/mips/kernel/setup.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/arch/mips/kernel/setup.c b/arch/mips/kernel/setup.c
index 23a140327a0b..f1da2b2ba5e9 100644
--- a/arch/mips/kernel/setup.c
+++ b/arch/mips/kernel/setup.c
@@ -653,6 +653,8 @@ static void __init arch_mem_init(char **cmdline_p)
*/
memblock_set_current_limit(PFN_PHYS(max_low_pfn));
+ memblock_reserve(0, PAGE_SIZE * NODE_DATA(0)->node_start_pfn);
+
which platform needs this ? This look it should be better fixed in
the platform memory registration code.
Thomas.
I have a problem on the loogson platform.
I had checked a Loongson 3A4000 board (Lemote-A1901) with UEFI firmware
and the region is reserved by firmware.
Hmm, you'd better contact vendor to fix the firmware. If it's not
possible then workaround it in arch/mips/loongson64/numa.c
Thanks.
- Jiaxun
