Kernel tainted 512 due to WARNING kernel/rcu/tree_plugin.h:318 rcu_note_context_switch+0x256/0x2a0

Solution In Progress - Updated -

Environment

  • Red Hat Enterprise Linux 9.4
  • “Lenovo P14s Gen 5 based on AMD Ryzen 9/7/5 PRO 8000 series (Hawk Point)”
  • "HP ZBook Power 16 inch G11 A Mobile Workstation PC based on AMD Ryzen 9/7/5 PRO 8000 series (Hawk Point)"

Issue

Kernel logged Voluntary context switch within RCU read-side critical section! message followed by WARNING: WARNING: CPU: 0 PID: 20 at kernel/rcu/tree_plugin.h:318 rcu_note_context_switch+0x256/0x2a0

Resolution

  • The "AMD PMF"driver is used to enable the Smart Builder PC solution, but this solution is NOT supported with RHEL9.4 or with AMD Hawk Point platforms. When hardware vendors load the "AMD PMF" driver by default on these platforms, this warning will appear in the system logs.
  • This is a cosmetic, benign kernel warning which is harmless. And customers can use "modprobe.blacklist=amd_pmf" to disable it.
  • This will be fixed in a later Red Hat Enterprise Linux 9.x with a patch that hides the error message.

Diagnostic Steps

  • Verify the loaded module
# cat lsmod |grep pmf
amd_pmf                49152  0
platform_profile       16384  2 amd_pmf,thinkpad_acpi
  • Warning messages are captured in /var/log/dmesg file.
[ 16.467878] Voluntary context switch within RCU read-side critical section!
[ 16.467880] WARNING: CPU: 0 PID: 20 at kernel/rcu/tree_plugin.h:318 rcu_note_context_switch+0x256/0x2a0
[ 16.467889] Modules linked in: nft_fib_inet nft_fib_ipv4 nft_fib_ipv6 nft_fib nft_reject_inet nf_reject_ipv4 nf_reject_ipv6 nft_reject nft_ct nft_chain_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 ip_set nf_tables nfnetlink qrtr bnep sunrpc vfat fat mt7921e snd_sof_amd_vangogh snd_sof_amd_rembrandt snd_hda_codec_realtek mt7921_common snd_sof_amd_renoir snd_sof_amd_acp joydev snd_hda_codec_generic mt792x_lib snd_sof_pci snd_sof_xtensa_dsp ledtrig_audio mt76_connac_lib snd_sof snd_hda_codec_hdmi mt76 snd_hda_intel snd_sof_utils snd_intel_dspcfg mac80211 snd_intel_sdw_acpi snd_soc_core intel_rapl_msr intel_rapl_common snd_hda_codec edac_mce_amd uvcvideo snd_compress snd_hda_core hid_multitouch snd_pci_ps uvc btusb snd_pci_acp6x videobuf2_vmalloc snd_hwdep videobuf2_memops btrtl kvm_amd snd_seq btbcm btintel snd_seq_device videobuf2_v4l2 btmtk libarc4 snd_pcm bluetooth videobuf2_common kvm videodev hp_wmi cfg80211 snd_pci_acp5x snd_timer irqbypass mc rapl sparse_keymap pcspkr
[ 16.467965] wmi_bmof snd_rn_pci_acp3x snd i2c_piix4 snd_acp_config k10temp soundcore rfkill snd_soc_acpi amd_pmf i2c_designware_platform wireless_hotkey platform_profile i2c_designware_core amd_pmc xfs libcrc32c amdgpu nouveau mxm_wmi i2c_algo_bit drm_ttm_helper ttm drm_suballoc_helper amdxcp drm_buddy drm_exec gpu_sched drm_display_helper drm_kms_helper rtsx_pci_sdmmc nvme syscopyarea sysfillrect crct10dif_pclmul sysimgblt fb_sys_fops crc32_pclmul mmc_core crc32c_intel nvme_core drm ccp ghash_clmulni_intel igc amd_sfh sp5100_tco nvme_common r8169 rtsx_pci cec t10_pi realtek video wmi i2c_hid_acpi i2c_hid serio_raw dm_mirror dm_region_hash dm_log dm_mod fuse
[ 16.468030] CPU: 0 PID: 20 Comm: kworker/0:1 Not tainted 5.14.0-427.13.1.el9_4.x86_64 #1
[ 16.468033] Hardware name: HP HP ZBook Power 16 inch G11 A Mobile Workstation PC/8C95, BIOS W85 Ver. 01.01.01 03/21/2024
[ 16.468035] Workqueue: events power_supply_changed_work
[ 16.468041] RIP: 0010:rcu_note_context_switch+0x256/0x2a0
[ 16.468044] Code: 08 f0 83 44 24 fc 00 48 89 de 4c 89 ef e8 f2 8e ff ff e9 36 fe ff ff 48 c7 c7 28 e9 f2 9c c6 05 50 a8 f7 01 01 e8 5a 37 f5 ff <0f> 0b e9 f2 fd ff ff a9 ff ff ff 7f 0f 84 8d fe ff ff 65 48 8b 3c
[ 16.468046] RSP: 0018:ffffbd83c01e7788 EFLAGS: 00010086
[ 16.468048] RAX: 0000000000000000 RBX: ffff98f6ae833ec0 RCX: 0000000000000027
[ 16.468050] RDX: 0000000000000027 RSI: 00000000ffff868b RDI: ffff98f6ae820848
[ 16.468052] RBP: 0000000000000000 R08: 00000000000013a1 R09: ffffbd83c01e7710
[ 16.468053] R10: 0000000000000001 R11: 0000000000000040 R12: ffff98f34089c680
[ 16.468055] R13: 0000000000000001 R14: 0000000000000000 R15: ffff98f3410f8f60
[ 16.468056] FS: 0000000000000000(0000) GS:ffff98f6ae800000(0000) knlGS:0000000000000000
[ 16.468058] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 16.468060] CR2: 00007ffff03a0084 CR3: 000000023a210000 CR4: 0000000000750ef0
[ 16.468062] PKRU: 55555554
[ 16.468063] Call Trace:
[ 16.468066] <TASK>
[ 16.468067] ? srso_alias_return_thunk+0x5/0xfbef5
[ 16.468072] ? show_trace_log_lvl+0x26e/0x2df
[ 16.468079] ? show_trace_log_lvl+0x26e/0x2df
[ 16.468084] ? __schedule+0x6e/0x550
[ 16.468089] ? rcu_note_context_switch+0x256/0x2a0
[ 16.468091] ? __warn+0x81/0x110
[ 16.468095] ? rcu_note_context_switch+0x256/0x2a0
[ 16.468097] ? report_bug+0x10a/0x140
[ 16.468102] ? handle_bug+0x3c/0x70
[ 16.468105] ? exc_invalid_op+0x14/0x70
[ 16.468107] ? asm_exc_invalid_op+0x16/0x20
[ 16.468113] ? rcu_note_context_switch+0x256/0x2a0
[ 16.468115] ? rcu_note_context_switch+0x256/0x2a0
[ 16.468118] __schedule+0x6e/0x550
[ 16.468121] ? srso_alias_return_thunk+0x5/0xfbef5
[ 16.468123] ? __mod_timer+0x286/0x3d0
[ 16.468127] schedule+0x2d/0x70
[ 16.468130] schedule_timeout+0x88/0x160
[ 16.468134] ? __pfx_process_timeout+0x10/0x10
[ 16.468138] ec_guard+0x1b3/0x200
[ 16.468142] ? __pfx_autoremove_wake_function+0x10/0x10
[ 16.468146] acpi_ec_transaction_unlocked+0x119/0x320
[ 16.468151] acpi_ec_transaction+0x6c/0x150
[ 16.468153] ? srso_alias_return_thunk+0x5/0xfbef5
[ 16.468156] acpi_ec_space_handler+0x187/0x280
[ 16.468160] acpi_ev_address_space_dispatch+0x16b/0x3c0
[ 16.468163] ? __pfx_acpi_ec_space_handler+0x10/0x10
[ 16.468166] acpi_ex_access_region+0x5b/0xd0
[ 16.468170] acpi_ex_field_datum_io+0x73/0x2e0
[ 16.468173] acpi_ex_write_with_update_rule+0x94/0xf0
[ 16.468176] ? kmem_cache_alloc+0x17d/0x340
[ 16.468180] acpi_ex_insert_into_field+0x282/0x370
[ 16.468183] acpi_ex_write_data_to_field+0x7c/0x170
[ 16.468186] acpi_ex_store_object_to_node+0x160/0x210
[ 16.468190] acpi_ex_opcode_1A_1T_1R+0x24e/0x620
[ 16.468194] acpi_ds_exec_end_op+0x284/0x510
[ 16.468197] acpi_ps_parse_loop+0xf4/0x680
[ 16.468200] acpi_ps_parse_aml+0x17a/0x3d0
[ 16.468203] acpi_ps_execute_method+0x137/0x270
[ 16.468206] acpi_ns_evaluate+0x1f4/0x2e0
[ 16.468209] acpi_evaluate_object+0x134/0x2f0
[ 16.468211] ? srso_alias_return_thunk+0x5/0xfbef5
[ 16.468215] apmf_if_call+0xb2/0x100 [amd_pmf]
[ 16.468221] apmf_os_power_slider_update+0x4c/0x90 [amd_pmf]
[ 16.468225] amd_pmf_power_slider_update_event+0x31/0x70 [amd_pmf]
[ 16.468229] amd_pmf_pwr_src_notify_call+0xab/0xc0 [amd_pmf]
[ 16.468232] atomic_notifier_call_chain+0x4e/0x80
[ 16.468235] ? srso_alias_return_thunk+0x5/0xfbef5
[ 16.468237] power_supply_changed_work+0x81/0xf0
[ 16.468240] process_one_work+0x1e2/0x3b0
[ 16.468243] ? __pfx_worker_thread+0x10/0x10
[ 16.468245] worker_thread+0x50/0x3a0
[ 16.468247] ? __pfx_worker_thread+0x10/0x10
[ 16.468249] kthread+0xdd/0x100
[ 16.468252] ? __pfx_kthread+0x10/0x10
[ 16.468254] ret_from_fork+0x29/0x50
[ 16.468261] </TASK>
[ 16.468262] ---[ end trace fd9ce2d5d382050c ]---

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