Subject: Re: linux-next: Tree for May 2

From: "Jain, Ayush" <[email-masked]>
Date: Mon, 5 May 2025 09:20:54 +0530

Hello Stephen,

On 5/2/2025 3:18 PM, Stephen Rothwell wrote:
> Hi all,
> 
> Changes since 20250501:
> 
> I have reverted a commit in the mm-nonmm-unstable tree that was causing
> build failures.
> 
> The scmi tree gained a build failure for which I disabled a CONFIG option.
> 
> The tip tree still had its build failure so I used the version from
> next-20250414.
> 
> The ipmi tree gained conflicts against Linus' tree.
> 
> The char-misc tree still had its build failure so I used the version
> from next-20250428.
> 
> Non-merge commits (relative to Linus' tree): 7260
>  7323 files changed, 304374 insertions(+), 157636 deletions(-)
> 
> ----------------------------------------------------------------------------
> 
> I have created today's linux-next tree at
> git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git
> (patches at http://www.kernel.org/pub/linux/kernel/next/ ).  If you
> are tracking the linux-next tree using git, you should not use "git pull"
> to do so as that will try to merge the new linux-next release with the
> old one.  You should use "git fetch" and checkout or reset to the new
> master.
> 
> You can see which trees have been included by looking in the Next/Trees
> file in the source.  There is also the merge.log file in the Next
> directory.  Between each merge, the tree was built with a ppc64_defconfig
> for powerpc, an allmodconfig for x86_64, a multi_v7_defconfig for arm
> and a native build of tools/perf. After the final fixups (if any), I do
> an x86_64 modules_install followed by builds for x86_64 allnoconfig,
> powerpc allnoconfig (32 and 64 bit), ppc44x_defconfig, allyesconfig
> and pseries_le_defconfig and i386, arm64, s390, sparc and sparc64
> defconfig and htmldocs. And finally, a simple boot test of the powerpc
> pseries_le_defconfig kernel in qemu (with and without kvm enabled).
> 
> Below is a summary of the state of the merge.
> 
> I am currently merging 395 trees (counting Linus' and 150 trees of bug
> fix patches pending for the current release).
> 
> Stats about the size of the tree over time can be seen at
> http://neuling.org/linux-next-size.html .
> 
> Thanks to Randy Dunlap for doing many randconfig builds.  And to Paul
> Gortmaker for triage and bug fixes.
> 

Hitting Kernel Panic on latest-next while running rcutorture tests

37ff6e9a2ce3 ("Add linux-next specific files for 20250502")

Attaching kernel logs below:

[ 1070.635450] rcu-torture: rcu_torture_read_exit: End of episode
[ 1074.047617] BUG: kernel NULL pointer dereference, address:
0000000000000498
[ 1074.054577] #PF: supervisor read access in kernel mode
[ 1074.059718] #PF: error_code(0x0000) - not-present page
[ 1074.064856] PGD 0 P4D 0
[ 1074.067395] Oops: Oops: 0000 [#1] SMP NOPTI
[ 1074.071583] CPU: 48 UID: 0 PID: 307 Comm: migration/48 Not tainted
6.15.0-rc4-next-20250502-37ff6e9a2ce3-1746413815614 #1 PREEMPT(voluntary)
[ 1074.084258] Hardware name: Dell Inc. PowerEdge R6515/0R4CNN, BIOS
2.16.0 07/09/2024
[ 1074.091913] Stopper: multi_cpu_stop+0x0/0x130 <- migrate_swap+0xad/0x120
[ 1074.098619] RIP: 0010:__migrate_swap_task+0x2e/0x180
[ 1074.103585] Code: 00 55 48 89 e5 41 57 41 56 41 55 41 54 49 89 fc 53
48 63 de 48 83 87 a0 03 00 00 01 66 90 4c 8b af 50 09 00 00 e8 c2 47 07
00 <49> 8b bd 98 04 00 00 e8 26 11 36 00 48 89 c7 48 85 c0 74 0a be 3b
[ 1074.122332] RSP: 0018:ffffa4bc4d54bdb0 EFLAGS: 00010002
[ 1074.127557] RAX: 0000000000000001 RBX: 0000000000000007 RCX:
0000000000000000
[ 1074.134688] RDX: ffff8d80c01fcec0 RSI: 0000000000000007 RDI:
ffff8d2153c93480
[ 1074.141822] RBP: ffffa4bc4d54bdd8 R08: 000000fa1239fb41 R09:
ffff8d9f3e832380
[ 1074.148955] R10: 0000000000000004 R11: 0000000000000001 R12:
ffff8d2153c93480
[ 1074.156088] R13: 0000000000000000 R14: ffff8d60dc9ac14c R15:
ffff8d2153c9414c
[ 1074.163218] FS:  0000000000000000(0000) GS:ffff8d9f8a626000(0000)
knlGS:0000000000000000
[ 1074.171306] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1074.177051] CR2: 000000000000049op+0x10/0x10
[ 1074.203665]  cpu_stopper_thread+0xa6/0x160
[ 1074.207767]  smpboot_thread_fn+0x122/0x280
[ 1074.211866]  kthread+0x11a/0x230
[ 1074.215098]  ? __pfx_smpboot_thread_fn+0x10/0x10
[ 1074.219717]  ? _raw_spin_unlock_irq+0x28/0x50
[ 1074.224076]  ? __pfx_kthread+0x10/0x10
[ 1074.227829]  ret_from_fork+0x40/0x60
[ 1074.231407]  ? __pfx_kthread+0x10/0x10
[ 1074.235161]  ret_from_fork_asm+0x1a/0x30
[ 1074.239089]  </TASK>
[ 1074.241279] Modules linked in: rcutorture torture xt_tcpudp
nft_compat nft_chain_nat nf_nat nf_conntrack nf_defrag_ipv6
nf_defrag_ipv4 nf_tables nfnetlink binfmt_misc ipmi_ssif nls_iso8859_1
intel_rapl_msr intel_rapl_common amd64_edac edac_mce_amd kvm_amd
dell_smbios wmi_bmof kvm dell_wmi_descriptor dcdbas rapl ccp k10temp
acpi_power_meter ptdma wmi ipmi_si acpi_ipmi ipmi_devintf
ipmi_msghandler mac_hid sch_fq_codel dm_multipath scsi_dh_rdac
scsi_dh_emc scsi_dh_alua msr fuse efi_pstore ip_tables x_tables autofs4
btrfs blake2b_generic raid10 raid456 async_raid6_recov async_memcpy
async_pq async_xor async_tx xor raid6_pq raid1 raid0 mgag200
drm_client_lib i2c_algo_bit drm_shmem_helper drm_kms_helper nvme
ghash_clmulni_intel drm tg3 mpt3sas nvme_core ahci bnxt_en i2c_piix4
raid_class libahci i2c_smbus scsi_transport_sas aesni_intel [last
unloaded: torture]
[ 1074.316817] CR2: 0000000000000498
[ 1074.320135] ---[ end trace 0000000000000000 ]---
[ 1074.418846] pstore: backend (erst) writing error (-28)
[ 1074.423983] RIP: 0010:__migrate_swap_task+0x2e/0x180
[ 1074.428949] Code: 00 55 48 89 e5 41 57 41 56 41 55 41 54 49 89 fc 53
48 63 de 48 83 87 a0 03 00 00 01 66 90 4c 8b af 50 09 00 00 e8 c2 47 07
00 <49> 8b bd 98 04 00 00 e8 26 11 36 00 48 89 c7 48 85 c0 74 0a be 3b
[ 1074.447694] RSP: 0018:ffffa4bc4d54bdb0 EFLAGS: 00010002
[ 1074.452919] RAX: 0000000000000001 RBX: 0000000000000007 RCX:
0000000000000000
[ 1074.460051] RDX: ffff8d80c01fcec0 RSI: 0000000000000007 RDI:
ffff8d2153c93480
[ 1074.467184] RBP: ffffa4bc4d54bdd8 R08: 000000fa1239fb41 R09:
ffff8d9f3e832380
[ 1074.474317] R10: 0000000000000004 R11: 0000000000000001 R12:
ffff8d2153c93480
[ 1074.481450] R13: 0000000000000000 R14: ffff8d60dc9ac14c R15:
ffff8d2153c9414c
[ 1074.488581] FS:  0000000000000000(0000) GS:ffff8d9f8a626000(0000)
knlGS:0000000000000000
[ 1074.496666] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1074.502414] CR2: 0000000000000498 CR3: 000000409341a002 CR4:
0000000000770ef0
[ 1074.509547] PKRU: 55555554
[ 1074.512258] note: migration/48[307] exited with irqs disabled
[ 1084.683268] watchdog: CPU6: Watchdog detected hard LOCKUP on cpu 6
[ 1084.683274] Modules linked in: rcutorture torture xt_tcpudp
nft_compat nft_chain_nat nf_nat nf_conntrack nf_defrag_ipv6
nf_defrag_ipv4 nf_tables nfnetlink binfmt_misc ipmi_ssif nls_iso8859_1
intel_rapl_msr intel_rapl_common amd64_edac edac_mce_amd kvm_amd
dell_smbios wmi_bmof kvm dell_wmi_descriptor dcdbas rapl ccp k10temp
acpi_power_meter ptdma wmi ipmi_si acpi_ipmi ipmi_devintf
ipmi_msghandler mac_hid sch_fq_codel dm_multipath scsi_dh_rdac
scsi_dh_emc scsi_dh_alua msr fuse efi_pstore ip_tables x_tables autofs4
btrfs blake2b_generic raid10 raid456 async_raid6_recov async_memcpy
async_pq async_xor async_tx xor raid6_pq raid1 raid0 mgag200
drm_client_lib i2c_algo_bit drm_shmem_helper drm_kms_helper nvme
ghash_clmulni_intel drm tg3 mpt3sas nvme_core ahci bnxt_en i2c_piix4
raid_class libahci i2c_smbus scsi_transport_sas aesni_intel [last
unloaded: torture]
[ 1084.683352] CPU: 6 UID: 0 PID: 83659 Comm: rcu_torture_rea Tainted: G
     D             6.15.0-rc4-next-20250502-37ff6e9a2ce3-1746413815614
#1 PREEMPT(voluntary)
[ 1084.683357] Tainted: [D]=DIE
[ 1084.683358] Hardware name: Dell Inc. PowerEdge R6515/0R4CNN, BIOS
2.16.0 07/09/2024
[ 1084.683360] RIP: 0010:native_queued_spin_lock_slowpath+0x2b4/0x300
[ 1084.683368] Code: 63 ff 4c 8d a8 c0 d1 20 b4 49 81 ff ff 1f 00 00 77
46 4e 03 2c fd e0 5e f7 b2 49 89 5d 00 8b 43 08 85 c0 75 09 f3 90 8b 43
08 <85> c0 74 f7 48 8b 13 48 85 d2 0f 84 5e ff ff ff 0f 0d 0a e9 56 ff
[ 1084.683370] RSP: 0018:ffffa4bc6b503a28 EFLAGS: 00000046
[ 1084.683373] RAX: 0000000000000000 RBX: ffff8d403f9b31c0 RCX:
0000000000000008
[ 1084.683375] RDX: 0000000000000047 RSI: 00000000011c0100 RDI:
ffff8d403f9f2280
[ 1084.683376] RBP: ffffa4bc6b503a50 R08: 0000000000000080 R09:
ffffffffffffff00
[ 1084.683377] R10: 0000000000000000 R11: 0000000000000080 R12:
ffff8d403f9f2280
[ 1084.683379] R13: ffff8d403fdb31c0 R14: 00000000001c0000 R15:
0000000000000046
[ 1084.683380] FS:  0000000000000000(0000) GS:ffff8d408b7a6000(0000)
knlGS:0000000000000000
[ 1084.683382] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1084.683384] CR2: 00007f54f32a3010 CR3: 000000209f547008 CR4:
0000000000770ef0
[ 1084.683385] PKRU: 55555554
[ 1084.683387] Call Trace:
[ 1084.683388]  <TASK>
[ 1084.683395]  _raw_spin_lock+0x3c/0x50
[ 1084.683399]  raw_spin_rq_lock_nested+0x28/0xa0
[ 1084.683404]  _raw_spin_rq_lock_irqsave+0x29/0x60
[ 1084.683408]  sched_balance_rq+0x6c8/0x1430
[ 1084.683412]  ? srso_alias_return_thunk+0x5/0xfbef5
[ 1084.683422]  sched_balance_newidle+0x1ba/0x450
[ 1084.683426]  pick_next_task_fair+0x39/0x500
[ 1084.683429]  ? srso_alias_return_thunk+0x5/0xfbef5
[ 1084.683431]  ? dequeue_task_fair+0xb1/0x1b0
[ 1084.683433]  ? srso_alias_return_thunk+0x5/0xfbef5
[ 1084.683436]  __pick_next_task+0x43/0x1b0
[ 1084.683440]  __schedule+0x20c/0x15b0
[ 1084.683443]  ? trace_preempt_on+0x1f/0x70
[ 1084.683447]  ? srso_alias_return_thunk+0x5/0xfbef5
[ 1084.683450]  ? preempt_count_sub+0x50/0x80
[ 1084.683452]  ? srso_alias_return_thunk+0x5/0xfbef5
[ 1084.683455]  ? hrtimer_start_range_ns+0x137/0x4b0
[ 1084.683459]  ? srso_alias_return_thunk+0x5/0xfbef5
[ 1084.683463]  schedule+0x_us+0x23/0x30 [torture]
[ 1084.683489]  rcu_torture_reader+0x138/0x200 [rcutorture]
[ 1084.683496]  ? __pfx_rcu_torture_timer+0x10/0x10 [rcutorture]
[ 1084.683503]  kthread+0x11a/0x230
[ 1084.683507]  ? __pfx_rcu_torture_reader+0x10/0x10 [rcutorture]
[ 1084.683512]  ? _raw_spin_unlock_irq+0x28/0x50
[ 1084.683516]  ? __pfx_kthread+0x10/0x10
[ 1084.683519]  ret_from_fork+0x40/0x60
[ 1084.683524]  ? __pfx_kthread+0x10/0x10
[ 1084.683527]  ret_from_fork_asm+0x1a/0x30
[ 1084.683535]  </TASK>
[ 1084.683537] Kernel panic - not syncing: Hard LOCKUP
[ 1086.154471] Shutting down cpus with NMI
[ 1086.169269] Kernel Offset: 0x30200000 from 0xffffffff81000000
(relocation range: 0xffffffff80000000-0xffffffffbfffffff)
[ 1086.583614] ---[ end Kernel panic - not syncing: Hard LOCKUP ]---

Test recreate steps:
1. Load rcutorture module to machine
2. Toggle cpu status (Online/offline)

https://github.com/avocado-framework-tests/avocado-misc-tests/blob/master/generic/rcutorture.py

Let me know, if more details are needed from my end

If you fix the issue in a separate patch/commit (i.e. not just a new
version of
the same patch/commit), kindly add following tags
Reported-by: Ayush Jain <[email-masked]>

Thanks and Regards,
Ayush Jain