> On Mon 06-05-19 22:06:38, Zhiqiang Liu wrote:
>> From: Kai Shen <shenkai8@xxxxxxxxxx>
>>
>> spinlock recursion happened when do LTP test:
>> #!/bin/bash
>> ./runltp -p -f hugetlb &
>> ./runltp -p -f hugetlb &
>> ./runltp -p -f hugetlb &
>> ./runltp -p -f hugetlb &
>> ./runltp -p -f hugetlb &
>>
>> The dtor returned by get_compound_page_dtor in __put_compound_page
>> may be the function of free_huge_page which will lock the hugetlb_lock,
>> so don't put_page in lock of hugetlb_lock.
>>
>> BUG: spinlock recursion on CPU#0, hugemmap05/1079
>> lock: hugetlb_lock+0x0/0x18, .magic: dead4ead, .owner: hugemmap05/1079, .owner_cpu: 0
>> Call trace:
>> dump_backtrace+0x0/0x198
>> show_stack+0x24/0x30
>> dump_stack+0xa4/0xcc
>> spin_dump+0x84/0xa8
>> do_raw_spin_lock+0xd0/0x108
>> _raw_spin_lock+0x20/0x30
>> free_huge_page+0x9c/0x260
>> __put_compound_page+0x44/0x50
>> __put_page+0x2c/0x60
>> alloc_surplus_huge_page.constprop.19+0xf0/0x140
>> hugetlb_acct_memory+0x104/0x378
>> hugetlb_reserve_pages+0xe0/0x250
>> hugetlbfs_file_mmap+0xc0/0x140
>> mmap_region+0x3e8/0x5b0
>> do_mmap+0x280/0x460
>> vm_mmap_pgoff+0xf4/0x128
>> ksys_mmap_pgoff+0xb4/0x258
>> __arm64_sys_mmap+0x34/0x48
>> el0_svc_common+0x78/0x130
>> el0_svc_handler+0x38/0x78
>> el0_svc+0x8/0xc
>>
>> Fixes: 9980d744a0 ("mm, hugetlb: get rid of surplus page accounting tricks")
>> Signed-off-by: Kai Shen <shenkai8@xxxxxxxxxx>
>> Signed-off-by: Feilong Lin <linfeilong@xxxxxxxxxx>
>> Reported-by: Wang Wang <wangwang2@xxxxxxxxxx>
>> Acked-by: Michal Hocko <mhocko@xxxxxxxx>
>> ---
>> v1->v2: add Acked-by: Michal Hocko <mhocko@xxxxxxxx>
>
> A new version for single ack is usually an overkill and only makes the
> situation more confusing. You have also didn't add Cc: stable as
> suggested during the review. That part is arguably more important.
>
> You also haven't CCed Andrew (now done) and your patch will not get
> merged without him applying it. Anyway, let's wait for Andrew to pick
> this patch up.
>
Thank you for your patience. I am sorry for misunderstanding your advice
in your last mail.
Does adding Cc: stable mean adding Cc: <stable@xxxxxxxxxxxxxxx>
tag in the patch or Ccing stable@xxxxxxxxxxxxxxx when sending the new mail?
You are very nice. Thanks again.
>> mm/hugetlb.c | 3 ++-
>> 1 file changed, 2 insertions(+), 1 deletion(-)
>>
>> diff --git a/mm/hugetlb.c b/mm/hugetlb.c
>> index 6cdc7b2..c1e7b81 100644
>> --- a/mm/hugetlb.c
>> +++ b/mm/hugetlb.c
>> @@ -1574,8 +1574,9 @@ static struct page *alloc_surplus_huge_page(struct hstate *h, gfp_t gfp_mask,
>> */
>> if (h->surplus_huge_pages >= h->nr_overcommit_huge_pages) {
>> SetPageHugeTemporary(page);
>> + spin_unlock(&hugetlb_lock);
>> put_page(page);
>> - page = NULL;
>> + return NULL;
>> } else {
>> h->surplus_huge_pages++;
>> h->surplus_huge_pages_node[page_to_nid(page)]++;
>> --
>> 1.8.3.1
>>
>
