On Tue, Apr 30, 2024 at 03:43:31PM +0800, Miaohe Lin wrote: > When I did memory failure tests recently, below warning occurs: > > DEBUG_LOCKS_WARN_ON(1) > WARNING: CPU: 8 PID: 1011 at kernel/locking/lockdep.c:232 __lock_acquire+0xccb/0x1ca0 > Modules linked in: mce_inject hwpoison_inject > CPU: 8 PID: 1011 Comm: bash Kdump: loaded Not tainted 6.9.0-rc3-next-20240410-00012-gdb69f219f4be #3 > Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014 > RIP: 0010:__lock_acquire+0xccb/0x1ca0 > RSP: 0018:ffffa7a1c7fe3bd0 EFLAGS: 00000082 > RAX: 0000000000000000 RBX: eb851eb853975fcf RCX: ffffa1ce5fc1c9c8 > RDX: 00000000ffffffd8 RSI: 0000000000000027 RDI: ffffa1ce5fc1c9c0 > RBP: ffffa1c6865d3280 R08: ffffffffb0f570a8 R09: 0000000000009ffb > R10: 0000000000000286 R11: ffffffffb0f2ad50 R12: ffffa1c6865d3d10 > R13: ffffa1c6865d3c70 R14: 0000000000000000 R15: 0000000000000004 > FS: 00007ff9f32aa740(0000) GS:ffffa1ce5fc00000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: 00007ff9f3134ba0 CR3: 00000008484e4000 CR4: 00000000000006f0 > Call Trace: > <TASK> > lock_acquire+0xbe/0x2d0 > _raw_spin_lock_irqsave+0x3a/0x60 > hugepage_subpool_put_pages.part.0+0xe/0xc0 > free_huge_folio+0x253/0x3f0 > dissolve_free_huge_page+0x147/0x210 > __page_handle_poison+0x9/0x70 > memory_failure+0x4e6/0x8c0 > hard_offline_page_store+0x55/0xa0 > kernfs_fop_write_iter+0x12c/0x1d0 > vfs_write+0x380/0x540 > ksys_write+0x64/0xe0 > do_syscall_64+0xbc/0x1d0 > entry_SYSCALL_64_after_hwframe+0x77/0x7f > RIP: 0033:0x7ff9f3114887 > RSP: 002b:00007ffecbacb458 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 > RAX: ffffffffffffffda RBX: 000000000000000c RCX: 00007ff9f3114887 > RDX: 000000000000000c RSI: 0000564494164e10 RDI: 0000000000000001 > RBP: 0000564494164e10 R08: 00007ff9f31d1460 R09: 000000007fffffff > R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000000c > R13: 00007ff9f321b780 R14: 00007ff9f3217600 R15: 00007ff9f3216a00 > </TASK> > Kernel panic - not syncing: kernel: panic_on_warn set ... > CPU: 8 PID: 1011 Comm: bash Kdump: loaded Not tainted 6.9.0-rc3-next-20240410-00012-gdb69f219f4be #3 > Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014 > Call Trace: > <TASK> > panic+0x326/0x350 > check_panic_on_warn+0x4f/0x50 > __warn+0x98/0x190 > report_bug+0x18e/0x1a0 > handle_bug+0x3d/0x70 > exc_invalid_op+0x18/0x70 > asm_exc_invalid_op+0x1a/0x20 > RIP: 0010:__lock_acquire+0xccb/0x1ca0 > RSP: 0018:ffffa7a1c7fe3bd0 EFLAGS: 00000082 > RAX: 0000000000000000 RBX: eb851eb853975fcf RCX: ffffa1ce5fc1c9c8 > RDX: 00000000ffffffd8 RSI: 0000000000000027 RDI: ffffa1ce5fc1c9c0 > RBP: ffffa1c6865d3280 R08: ffffffffb0f570a8 R09: 0000000000009ffb > R10: 0000000000000286 R11: ffffffffb0f2ad50 R12: ffffa1c6865d3d10 > R13: ffffa1c6865d3c70 R14: 0000000000000000 R15: 0000000000000004 > lock_acquire+0xbe/0x2d0 > _raw_spin_lock_irqsave+0x3a/0x60 > hugepage_subpool_put_pages.part.0+0xe/0xc0 > free_huge_folio+0x253/0x3f0 > dissolve_free_huge_page+0x147/0x210 > __page_handle_poison+0x9/0x70 > memory_failure+0x4e6/0x8c0 > hard_offline_page_store+0x55/0xa0 > kernfs_fop_write_iter+0x12c/0x1d0 > vfs_write+0x380/0x540 > ksys_write+0x64/0xe0 > do_syscall_64+0xbc/0x1d0 > entry_SYSCALL_64_after_hwframe+0x77/0x7f > RIP: 0033:0x7ff9f3114887 > RSP: 002b:00007ffecbacb458 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 > RAX: ffffffffffffffda RBX: 000000000000000c RCX: 00007ff9f3114887 > RDX: 000000000000000c RSI: 0000564494164e10 RDI: 0000000000000001 > RBP: 0000564494164e10 R08: 00007ff9f31d1460 R09: 000000007fffffff > R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000000c > R13: 00007ff9f321b780 R14: 00007ff9f3217600 R15: 00007ff9f3216a00 > </TASK> > > After git bisecting and digging into the code, I believe the root cause is > that _deferred_list field of folio is unioned with _hugetlb_subpool field. > In __update_and_free_hugetlb_folio(), folio->_deferred_list is > initialized leading to corrupted folio->_hugetlb_subpool when folio is > hugetlb. Later free_huge_folio() will use _hugetlb_subpool and above > warning happens. > > But it is assumed hugetlb flag must have been cleared when calling > folio_put() in update_and_free_hugetlb_folio(). This assumption is broken > due to below race: > > CPU1 CPU2 > dissolve_free_huge_page update_and_free_pages_bulk > update_and_free_hugetlb_folio hugetlb_vmemmap_restore_folios > folio_clear_hugetlb_vmemmap_optimized > clear_flag = folio_test_hugetlb_vmemmap_optimized > if (clear_flag) <-- False, it's already cleared. > __folio_clear_hugetlb(folio) <-- Hugetlb is not cleared. > folio_put > free_huge_folio <-- free_the_page is expected. > list_for_each_entry() > __folio_clear_hugetlb <-- Too late. > > Fix this issue by checking whether folio is hugetlb directly instead of > checking clear_flag to close the race window. > > Link: https://lkml.kernel.org/r/20240419085819.1901645-1-linmiaohe@xxxxxxxxxx > Fixes: 32c877191e02 ("hugetlb: do not clear hugetlb dtor until allocating vmemmap") > Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx> > Reviewed-by: Oscar Salvador <osalvador@xxxxxxx> > Cc: <stable@xxxxxxxxxxxxxxx> > Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> > (cherry picked from commit 52ccdde16b6540abe43b6f8d8e1e1ec90b0983af) > Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx> > --- > mm/hugetlb.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/mm/hugetlb.c b/mm/hugetlb.c > index a17950160395..3a0f6b78f925 100644 > --- a/mm/hugetlb.c > +++ b/mm/hugetlb.c > @@ -1782,7 +1782,7 @@ static void __update_and_free_hugetlb_folio(struct hstate *h, > * If vmemmap pages were allocated above, then we need to clear the > * hugetlb destructor under the hugetlb lock. > */ > - if (clear_dtor) { > + if (folio_test_hugetlb(folio)) { > spin_lock_irq(&hugetlb_lock); > __clear_hugetlb_destructor(h, folio); > spin_unlock_irq(&hugetlb_lock); > -- > 2.33.0 > > Again, this breaks the build, did you not test it? Always do so before sending it out :( thanks, greg k-h
