On Mon, Apr 12, 2021 at 3:07 AM Wang Yugui <wangyugui@xxxxxxxxxxxx> wrote:
>
> Hi,
>
> kernel BUG at mm/huge_memory.c:2736(linux 5.10.29) is triggered
> by some files write test.
>
> mm/huge_memory.c:
> if (IS_ENABLED(CONFIG_DEBUG_VM) && mapcount) {
> pr_alert("total_mapcount: %u, page_count(): %u\n",
> mapcount, count);
> if (PageTail(page))
> dump_page(head, NULL);
> dump_page(page, "total_mapcount(head) > 0");
> L2736: BUG();
> }
We just can tell the mapcount of the page is not zero from the current
log, it might mean the unmap_page() call is failed. It seems you have
CONFIG_DEBUG_VM enabled, could you please paste more log? There is
"VM_BUG_ON_PAGE(!unmap_success, page)" in unmap_page(). It should be
able to tell us if unmap_page() is failed or not, or something else
happened.
>
> kernel version:5.10.29
>
> kernel BUG at mm/huge_memory.c:2736
> invalid opcode: 0000 [#1] SMP NOPTI
> CPU:9 pid:351 Comm: kswapd0 Tainted: G S
> RIP: 0010:split_huge_page_to_list.cold.86+0x19/8x1b
> ...
> Call Trace:
> ? shrink_inactive_list+0x241/0x3d0
> deferred_split_scan+0x1ca/0x320
> do_shrink_slab+0x20f/0x2c0
> shrink_node+0x24b/0x6d0
> balanced_pgdat+0x2db/0x550
> kswaped+0x201/0x390
> ? finish_wait+0x80/0x80
> ? balance_pgdat+0x550/0x550
> kthread+0x116/0x130
> ? ktrhead_park+0x80/0x80
> ret_from_fork+0x1f/0x30
>
> see OOPS.jpg for more info.
>
> Best Regards
> Wang Yugui (wangyugui@xxxxxxxxxxxx)
> 2021/04/12
>
