On Thu, May 30, 2024 at 4:57 PM Zhaoyang Huang <huangzhaoyang@xxxxxxxxx> wrote: > > On Thu, May 30, 2024 at 4:49 PM Yafang Shao <laoar.shao@xxxxxxxxx> wrote: > > > > On Tue, May 21, 2024 at 3:42 AM Marcin Wanat <private@xxxxxxxxxxxxxx> wrote: > > > > > > On 15.04.2024 03:50, Zhaoyang Huang wrote: > > > > On Mon, Apr 15, 2024 at 8:09 AM Dave Chinner <david@xxxxxxxxxxxxx> > wrote: >> >> On Sat, Apr 13, 2024 at 10:01:27AM +0800, Zhaoyang > > > Huang wrote: >>> loop Dave, since he has ever helped set up an > > > reproducer in >>> https://lore.kernel.org/linux- >>> > > > mm/20221101071721.GV2703033@xxxxxxxxxxxxxxxxxxx/ @Dave Chinner , >>> I > > > would like to ask for your kindly help on if you can verify >>> this > > > patch on your environment if convenient. Thanks a lot. >> >> I don't > > > have the test environment from 18 months ago available any >> more. > > > Also, I haven't seen this problem since that specific test >> > > > environment tripped over the issue. Hence I don't have any way of >> > > > confirming that the problem is fixed, either, because first I'd >> have > > > to reproduce it... > Thanks for the information. I noticed that you > > > reported another soft > lockup which is related to xas_load since > > > NOV.2023. This patch is > supposed to be helpful for this. With regard > > > to the version timing, > this commit is actually a revert of <mm/thp: > > > narrow lru locking> > b6769834aac1d467fa1c71277d15688efcbb4d76 which is > > > merged before > v5.15. > > For saving your time, a brief description > > > below. IMO, b6769834aa > introduce a potential stall between freeze the > > > folio's refcnt and > store it back to 2, which have the > > > xas_load->folio_try_get_rcu loops > as livelock if it stalls the > > > lru_lock's holder. > > b6769834aa split_huge_page_to_list - > > > spin_lock(lru_lock) > xas_split(&xas, folio,order) > > > folio_refcnt_freeze(folio, 1 + > folio_nr_pages(folio0) + > > > spin_lock(lru_lock) xas_store(&xas, > offset++, head+i) > > > page_ref_add(head, 2) spin_unlock(lru_lock) > > Sorry in advance if the > > > above doesn't make sense, I am just a > developer who is also suffering > > > from this bug and trying to fix it > > > I am experiencing a similar error on dozens of hosts, with stack traces > > > that are all similar: > > > > > > [627163.727746] watchdog: BUG: soft lockup - CPU#77 stuck for 22s! > > > [file_get:953301] > > > [627163.727778] Modules linked in: xt_set ip_set_hash_net ip_set xt_CT > > > xt_conntrack nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 nft_compat > > > nf_tables nfnetlink sr_mod cdrom rfkill vfat fat intel_rapl_msr > > > intel_rapl_common intel_uncore_frequency intel_uncore_frequency_common > > > isst_if_common skx_edac nfit libnvdimm x86_pkg_temp_thermal > > > intel_powerclamp coretemp ipmi_ssif kvm_intel kvm irqbypass mlx5_ib rapl > > > iTCO_wdt intel_cstate intel_pmc_bxt ib_uverbs iTCO_vendor_support > > > dell_smbios dcdbas i2c_i801 intel_uncore uas ses mei_me ib_core > > > dell_wmi_descriptor wmi_bmof pcspkr enclosure lpc_ich usb_storage > > > i2c_smbus acpi_ipmi mei intel_pch_thermal ipmi_si ipmi_devintf > > > ipmi_msghandler acpi_power_meter joydev tcp_bbr fuse xfs libcrc32c raid1 > > > sd_mod sg mlx5_core crct10dif_pclmul crc32_pclmul crc32c_intel > > > polyval_clmulni mgag200 polyval_generic drm_kms_helper mlxfw > > > drm_shmem_helper ahci nvme mpt3sas tls libahci ghash_clmulni_intel > > > nvme_core psample drm igb t10_pi raid_class pci_hyperv_intf dca libata > > > scsi_transport_sas i2c_algo_bit wmi > > > [627163.727841] CPU: 77 PID: 953301 Comm: file_get Kdump: loaded > > > Tainted: G L 6.6.30.el9 #2 > > > [627163.727844] Hardware name: Dell Inc. PowerEdge R740xd/08D89F, BIOS > > > 2.21.2 02/19/2024 > > > [627163.727847] RIP: 0010:xas_descend+0x1b/0x70 > > > [627163.727857] Code: 57 10 48 89 07 48 c1 e8 20 48 89 57 08 c3 cc 0f b6 > > > 0e 48 8b 47 08 48 d3 e8 48 89 c1 83 e1 3f 89 c8 48 83 c0 04 48 8b 44 c6 > > > 08 <48> 89 77 18 48 89 c2 83 e2 03 48 83 fa 02 74 0a 88 4f 12 c3 48 83 > > > [627163.727859] RSP: 0018:ffffc90034a67978 EFLAGS: 00000206 > > > [627163.727861] RAX: ffff888e4f971242 RBX: ffffc90034a67a98 RCX: > > > 0000000000000020 > > > [627163.727863] RDX: 0000000000000002 RSI: ffff88a454546d80 RDI: > > > ffffc90034a67990 > > > [627163.727865] RBP: fffffffffffffffe R08: fffffffffffffffe R09: > > > 0000000000008820 > > > [627163.727867] R10: 0000000000008820 R11: 0000000000000000 R12: > > > ffffc90034a67a20 > > > [627163.727868] R13: ffffc90034a67a18 R14: ffffea00873e8000 R15: > > > ffffc90034a67a18 > > > [627163.727870] FS: 00007fc5e503b740(0000) GS:ffff88bfefd80000(0000) > > > knlGS:0000000000000000 > > > [627163.727871] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > > > [627163.727873] CR2: 000000005fb87b6e CR3: 00000022875e8006 CR4: > > > 00000000007706e0 > > > [627163.727875] DR0: 0000000000000000 DR1: 0000000000000000 DR2: > > > 0000000000000000 > > > [627163.727876] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: > > > 0000000000000400 > > > [627163.727878] PKRU: 55555554 > > > [627163.727879] Call Trace: > > > [627163.727882] <IRQ> > > > [627163.727886] ? watchdog_timer_fn+0x22a/0x2a0 > > > [627163.727892] ? softlockup_fn+0x70/0x70 > > > [627163.727895] ? __hrtimer_run_queues+0x10f/0x2a0 > > > [627163.727903] ? hrtimer_interrupt+0x106/0x240 > > > [627163.727906] ? __sysvec_apic_timer_interrupt+0x68/0x170 > > > [627163.727913] ? sysvec_apic_timer_interrupt+0x9d/0xd0 > > > [627163.727917] </IRQ> > > > [627163.727918] <TASK> > > > [627163.727920] ? asm_sysvec_apic_timer_interrupt+0x16/0x20 > > > [627163.727927] ? xas_descend+0x1b/0x70 > > > [627163.727930] xas_load+0x2c/0x40 > > > [627163.727933] xas_find+0x161/0x1a0 > > > [627163.727937] find_get_entries+0x77/0x1d0 > > > [627163.727944] truncate_inode_pages_range+0x244/0x3f0 > > > [627163.727950] truncate_pagecache+0x44/0x60 > > > [627163.727955] xfs_setattr_size+0x168/0x490 [xfs] > > > [627163.728074] xfs_vn_setattr+0x78/0x140 [xfs] > > > [627163.728153] notify_change+0x34f/0x4f0 > > > [627163.728158] ? _raw_spin_lock+0x13/0x30 > > > [627163.728165] ? do_truncate+0x80/0xd0 > > > [627163.728169] do_truncate+0x80/0xd0 > > > [627163.728172] do_open+0x2ce/0x400 > > > [627163.728177] path_openat+0x10d/0x280 > > > [627163.728181] do_filp_open+0xb2/0x150 > > > [627163.728186] ? check_heap_object+0x34/0x190 > > > [627163.728189] ? __check_object_size.part.0+0x5a/0x130 > > > [627163.728194] do_sys_openat2+0x92/0xc0 > > > [627163.728197] __x64_sys_openat+0x53/0x90 > > > [627163.728200] do_syscall_64+0x35/0x80 > > > [627163.728206] entry_SYSCALL_64_after_hwframe+0x4b/0xb5 > > > [627163.728210] RIP: 0033:0x7fc5e493e7fb > > > [627163.728213] Code: 25 00 00 41 00 3d 00 00 41 00 74 4b 64 8b 04 25 18 > > > 00 00 00 85 c0 75 67 44 89 e2 48 89 ee bf 9c ff ff ff b8 01 01 00 00 0f > > > 05 <48> 3d 00 f0 ff ff 0f 87 91 00 00 00 48 8b 54 24 28 64 48 2b 14 25 > > > [627163.728215] RSP: 002b:00007ffdd4e300e0 EFLAGS: 00000246 ORIG_RAX: > > > 0000000000000101 > > > [627163.728218] RAX: ffffffffffffffda RBX: 00007ffdd4e30180 RCX: > > > 00007fc5e493e7fb > > > [627163.728220] RDX: 0000000000000241 RSI: 00007ffdd4e30180 RDI: > > > 00000000ffffff9c > > > [627163.728221] RBP: 00007ffdd4e30180 R08: 00007fc5e4600040 R09: > > > 0000000000000001 > > > [627163.728223] R10: 00000000000001b6 R11: 0000000000000246 R12: > > > 0000000000000241 > > > [627163.728224] R13: 0000000000000000 R14: 00007fc5e4662fa8 R15: > > > 0000000000000000 > > > [627163.728227] </TASK> > > > > > > I have around 50 hosts handling high I/O (each with 20Gbps+ uplinks > > > and multiple NVMe drives), running RockyLinux 8/9. The stock RHEL > > > kernel 8/9 is NOT affected, and the long-term kernel 5.15.X is NOT affected. > > > However, with long-term kernels 6.1.XX and 6.6.XX, > > > (tested at least 10 different versions), this lockup always appears > > > after 2-30 days, similar to the report in the original thread. > > > The more load (for example, copying a lot of local files while > > > serving 20Gbps traffic), the higher the chance that the bug will appear. > > > > > > I haven't been able to reproduce this during synthetic tests, > > > but it always occurs in production on 6.1.X and 6.6.X within 2-30 days. > > > > We encountered a similar issue several months ago. Some of our > > production servers crashed within days after deploying the 6.1.y > > stable kernel. The soft lock info as follows, > > > > [282879.612238] watchdog: BUG: soft lockup - CPU#65 stuck for 101s! > > [container-execu:1572375] > > [282879.612513] Modules linked in: ebtable_filter ebtables xt_DSCP > > iptable_mangle iptable_raw xt_CT cls_bpf sch_ingress raw_diag > > unix_diag tcp_diag udp_diag inet_diag iptable_filter bpfilter > > xt_conntrack nf_nat nf_conntrack_netlink nfnetlink nf_conntrack > > nf_defrag_ipv6 nf_defrag_ipv4 bpf_preload binfmt_misc cuse fuse > > overlay af_packet bonding intel_rapl_msr intel_rapl_common > > 64_edac kvm_amd kvm irqbypass crct10dif_pclmul crc32_pclmul > > polyval_clmulni polyval_generic ghash_clmulni_intel sha512_ssse3 > > aesni_intel crypto_simd cryptd rapl pcspkr vfat fat xfs mlx5_ib(O) > > ib_uverbs(O) input_leds ib_core(O) sg ccp ptdma i2c_piix4 k10temp > > acpi_ipmi ipmi_si ipmi_devintf ipmi_msghandler acpi_cpufreq ip_tables > > ext4 mbcache crc32c_intel jbd2 mlx5_core(O) mlxfw(O) pci_hyperv_intf > > psample mlxdevm(O) mlx_compat(O) tls nvme ptp pps_core nvme_core > > sd_mod t10_pi ahci libahci libata > > [282879.612571] CPU: 65 PID: 1572375 Comm: container-execu Kdump: > > loaded Tainted: G W O L 6.1.38-rc3 #rc3.pdd > > [282879.612574] Hardware name: New H3C Technologies Co., Ltd. H3C > > UniServer R4950 G5/RS45M2C9S, BIOS 5.30 06/30/2021 > > [282879.612576] RIP: 0010:xas_descend+0x18/0x80 > > [282879.612583] Code: b6 e8 ec de 05 00 cc cc cc cc cc cc cc cc cc cc > > cc cc 0f b6 0e 48 8b 57 08 48 d3 ea 83 e2 3f 89 d0 48 83 c0 04 48 8b > > 44 c6 08 <48> 89 77 18 48 89 c1 83 e1 03 48 83 f9 02 75 08 48 3d fd 00 > > 00 00 > > [282879.612586] RSP: 0018:ffffad700b247c40 EFLAGS: 00000202 > > [282879.612588] RAX: ffff91d247a75d8a RBX: fffffffffffffffe RCX: > > 0000000000000006 > > [282879.612589] RDX: 0000000000000026 RSI: ffff91d473cb7b30 RDI: > > ffffad700b247c68 > > [282879.612591] RBP: ffffad700b247c48 R08: 0000000000000003 R09: > > fffffffffffffffe > > [282879.612592] R10: 0000000000001990 R11: 0000000000000003 R12: > > ffffad700b247cf8 > > [282879.612593] R13: ffffad700b247d70 R14: ffffad700b247cf8 R15: > > ffffdfcd2c778000 > > [282879.612594] FS: 00007f5f576fb740(0000) GS:ffff922df0840000(0000) > > knlGS:0000000000000000 > > [282879.612596] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > > [282879.612597] CR2: 00007fe797100600 CR3: 0000002b2468e000 CR4: > > 0000000000350ee0 > > [282879.612599] Call Trace: > > [282879.612601] <IRQ> > > [282879.612605] ? show_regs.cold+0x1a/0x1f > > [282879.612610] ? watchdog_timer_fn+0x1c4/0x220 > > [282879.612614] ? softlockup_fn+0x30/0x30 > > [282879.612616] ? __hrtimer_run_queues+0xa2/0x2b0 > > [282879.612620] ? hrtimer_interrupt+0x109/0x220 > > [282879.612622] ? __sysvec_apic_timer_interrupt+0x5e/0x110 > > [282879.612625] ? sysvec_apic_timer_interrupt+0x7b/0x90 > > [282879.612629] </IRQ> > > [282879.612630] <TASK> > > [282879.612631] ? asm_sysvec_apic_timer_interrupt+0x1b/0x20 > > [282879.612640] ? xas_descend+0x18/0x80 > > [282879.612641] ? xas_load+0x35/0x40 > > [282879.612643] xas_find+0x197/0x1d0 > > [282879.612645] find_get_entries+0x6e/0x170 > > [282879.612649] truncate_inode_pages_range+0x294/0x4c0 > > [282879.612655] ? __xfs_trans_commit+0x13c/0x3e0 [xfs] > > [282879.612787] ? kvfree+0x2c/0x40 > > [282879.612791] ? trace_hardirqs_off+0x36/0xf0 > > [282879.612795] truncate_inode_pages_final+0x44/0x50 > > [282879.612798] evict+0x177/0x190 > > [282879.612802] iput.part.0+0x183/0x1e0 > > [282879.612804] iput+0x1c/0x30 > > [282879.612806] do_unlinkat+0x1c7/0x2c0 > > [282879.612810] __x64_sys_unlinkat+0x38/0x70 > > [282879.612812] do_syscall_64+0x38/0x90 > > [282879.612815] entry_SYSCALL_64_after_hwframe+0x63/0xcd > > [282879.612818] RIP: 0033:0x7f5f56cf120d > > [282879.612827] Code: 69 5c 2d 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e > > 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 63 d2 48 63 ff b8 07 01 00 > > 00 0f 05 <48> 3d 00 f0 ff ff 77 02 f3 c3 48 8b 15 32 5c 2d 00 f7 d8 64 > > 89 02 > > [282879.612828] RSP: 002b:00007fff30375c48 EFLAGS: 00000206 ORIG_RAX: > > 0000000000000107 > > [282879.612830] RAX: ffffffffffffffda RBX: 0000000000000003 RCX: > > 00007f5f56cf120d > > [282879.612831] RDX: 0000000000000000 RSI: 0000000001640403 RDI: > > 0000000000000003 > > [282879.612832] RBP: 0000000001640403 R08: 0000000000000000 R09: > > 0000000001640403 > > [282879.612833] R10: 0000000000000100 R11: 0000000000000206 R12: > > 0000000000000003 > > [282879.612834] R13: 000000000163c5c0 R14: 00007fff30375c80 R15: > > 0000000000000000 > > [282879.612836] </TASK> > > > > > > Unfortunately, we couldn't reproduce the issue on our test servers. We > > worked around it by disabling CONFIG_XARRAY_MULTI. Since then, these > > production servers have been running smoothly for several months. > > > > > If anyone can provide a patch, I can test it on multiple machines > > > over the next few days. > It is highly appreciated that you could help to try below one which > works on my v6.6 based android. However, there is a hard lockup > reported on an ongoing regression test(not sure if caused by this > patch yet). Thank you! I'm sorry to inform you that our users are unwilling to experiment with these changes on our production servers again, and I am unable to reproduce the issue on our test servers. I am reporting this issue to highlight to the community that it is indeed a serious problem, and we should consider it carefully. > > mm/huge_memory.c | 22 ++++++++++++++-------- > 1 file changed, 14 insertions(+), 8 deletions(-) > > diff --git a/mm/huge_memory.c b/mm/huge_memory.c > index 064fbd90822b..5899906c326a 100644 > --- a/mm/huge_memory.c > +++ b/mm/huge_memory.c > @@ -2498,7 +2498,7 @@ static void __split_huge_page(struct page *page, > struct list_head *list, > { > struct folio *folio = page_folio(page); > struct page *head = &folio->page; > - struct lruvec *lruvec; > + struct lruvec *lruvec = folio_lruvec(folio); > struct address_space *swap_cache = NULL; > unsigned long offset = 0; > unsigned int nr = thp_nr_pages(head); > @@ -2513,9 +2513,6 @@ static void __split_huge_page(struct page *page, > struct list_head *list, > xa_lock(&swap_cache->i_pages); > } > > - /* lock lru list/PageCompound, ref frozen by page_ref_freeze */ > - lruvec = folio_lruvec_lock(folio); > - > ClearPageHasHWPoisoned(head); > > for (i = nr - 1; i >= 1; i--) { > @@ -2541,9 +2538,6 @@ static void __split_huge_page(struct page *page, > struct list_head *list, > } > > ClearPageCompound(head); > - unlock_page_lruvec(lruvec); > - /* Caller disabled irqs, so they are still disabled here */ > - > split_page_owner(head, nr); > > /* See comment in __split_huge_page_tail() */ > @@ -2560,7 +2554,6 @@ static void __split_huge_page(struct page *page, > struct list_head *list, > page_ref_add(head, 2); > xa_unlock(&head->mapping->i_pages); > } > - local_irq_enable(); > > if (nr_dropped) > shmem_uncharge(head->mapping->host, nr_dropped); > @@ -2631,6 +2624,7 @@ int split_huge_page_to_list(struct page *page, > struct list_head *list) > int extra_pins, ret; > pgoff_t end; > bool is_hzp; > + struct lruvec *lruvec; > > VM_BUG_ON_FOLIO(!folio_test_locked(folio), folio); > VM_BUG_ON_FOLIO(!folio_test_large(folio), folio); > @@ -2714,6 +2708,14 @@ int split_huge_page_to_list(struct page *page, > struct list_head *list) > > /* block interrupt reentry in xa_lock and spinlock */ > local_irq_disable(); > + > + /* > + * take lruvec's lock before freeze the folio to prevent the folio > + * remains in the page cache with refcnt == 0, which could lead to > + * find_get_entry enters livelock by iterating the xarray. > + */ > + lruvec = folio_lruvec_lock(folio); > + > if (mapping) { > /* > * Check if the folio is present in page cache. > @@ -2748,12 +2750,16 @@ int split_huge_page_to_list(struct page *page, > struct list_head *list) > } > > __split_huge_page(page, list, end); > > > > > > > > > > -- > > Regards > > Yafang -- Regards Yafang
