2022-11-10 08:07:28

by Sachin Sant

[permalink] [raw]
Subject: [6.1.0-rc4-next-20221109] Boot time warning kernel/module/main.c:852

While booting 6.1.0-rc4-next-20221109 next kernel on a IBM Power9 LPAR
following warning is seen:

[ 8.808868] ------------[ cut here ]------------
[ 8.808872] WARNING: CPU: 1 PID: 378 at kernel/module/main.c:852 module_put+0x48/0x100
[ 8.808881] Modules linked in: sr_mod(E) cdrom(E) sd_mod(E) sg(E) lpfc(E) nvmet_fc(E) nvmet(E) ibmvscsi(E) scsi_transport_srp(E) ibmveth(E) nvme_fc(E) nvme(E) nvme_fabrics(E) nvme_core(E) t10_pi(E) scsi_transport_fc(E) crc64_rocksoft(E) crc64(E) tg3(E) fuse(E)
[ 8.808912] sd 1:0:0:1: [sdc] Write Protect is off
[ 8.808913] CPU: 1 PID: 378 Comm: kworker/1:3 Tainted: G E 6.1.0-rc4-next-20221109 #1
[ 8.808916] Hardware name: IBM,8375-42A POWER9 (raw) 0x4e0202 0xf000005 of:IBM,FW950.01 (VL950_047) hv:phyp pSeries
[ 8.808924] Workqueue: kaluad alua_rtpg_work
[ 8.808931] NIP: c000000000236c18 LR: c0000000009ee680 CTR: 00000000007088ec
[ 8.808936] REGS: c000000007c37870 TRAP: 0700 Tainted: G E (6.1.0-rc4-next-20221109)
[ 8.808942] MSR: 800000000282b033 <SF,VEC,VSX,EE,FP,ME,IR,DR,RI,LE> CR: 88002884 XER: 20040007
[ 8.808957] CFAR: c000000000236c04 IRQMASK: 0
[ 8.808957] GPR00: c0000000009ee680 c000000007c37b10 c00000000137ec00 c008000001d3a500
[ 8.808957] GPR04: 0000000000000000 0000000000000000 0000000000000000 00000000000000ff
[ 8.808957] GPR08: 0000000000000001 0000000000000001 c008000001d3a8c0 c0000000029674a8
[ 8.808957] GPR12: 0000000000002000 c00000000d5cf300 c00000000018f3d8 c000000003ce4d00
[ 8.808957] GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
[ 8.808957] GPR20: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
[ 8.808957] GPR24: c0000000092b0e00 0000000000000000 c00000008ee81000 c0000000092b0fc0
[ 8.808957] GPR28: c000000007c37c10 c000000007c37c10 c008000001d3a500 c00000008ee81000
[ 8.809018] NIP [c000000000236c18] module_put+0x48/0x100
[ 8.809024] sd 1:0:0:1: [sdc] Write cache: disabled, read cache: enabled, supports DPO and FUA
[ 8.809024] LR [c0000000009ee680] scsi_device_put+0x50/0x70
[ 8.809035] Call Trace:
[ 8.809038] [c000000007c37b10] [c000000007c37b50] 0xc000000007c37b50 (unreliable)
[ 8.809045] [c000000007c37b50] [c0000000009ee674] scsi_device_put+0x44/0x70
[ 8.809053] [c000000007c37b80] [c000000000a10c70] alua_rtpg_work+0x210/0x920
[ 8.809059] [c000000007c37c90] [c000000000182314] process_one_work+0x2b4/0x5b0
[ 8.809066] [c000000007c37d30] [c000000000182688] worker_thread+0x78/0x600
[ 8.809072] [c000000007c37dc0] [c00000000018f4f4] kthread+0x124/0x130
[ 8.809079] [c000000007c37e10] [c00000000000cffc] ret_from_kernel_thread+0x5c/0x64
[ 8.809086] Instruction dump:
[ 8.809090] f821ffc1 41820034 395e03c0 7c0004ac 7d205028 2c090001 3929ffff 41c00010
[ 8.809101] 7d20512d
[ 8.809101] sd 1:0:0:1: [sdc] Preferred minimum I/O size 32768 bytes
[ 8.809102] 40c2ffec 7c0004ac 79290fe2 <0b090000> 60000000 38210040 ebc1fff0
[ 8.809115] ---[ end trace 0000000000000000 ]—

-next-20221108 was good. Git bisect points to following

commit 0b25e17e9018a0ea68a9f0b4787672e8c68fa8d5
Date: Mon Oct 31 15:47:25 2022 -0700
scsi: alua: Move a scsi_device_put() call out of alua_check_vpd()

Reverting this patch gets rid of the warning.

- Sachin



2022-11-10 18:35:47

by Bart Van Assche

[permalink] [raw]
Subject: Re: [6.1.0-rc4-next-20221109] Boot time warning kernel/module/main.c:852

On 11/10/22 00:01, Sachin Sant wrote:
> While booting 6.1.0-rc4-next-20221109 next kernel on a IBM Power9 LPAR
> following warning is seen:
>
> [ 8.808868] ------------[ cut here ]------------
> [ 8.808872] WARNING: CPU: 1 PID: 378 at kernel/module/main.c:852 module_put+0x48/0x100
> [ 8.809024] sd 1:0:0:1: [sdc] Write cache: disabled, read cache: enabled, supports DPO and FUA
> [ 8.809024] LR [c0000000009ee680] scsi_device_put+0x50/0x70
> [ 8.809035] Call Trace:
> [ 8.809038] [c000000007c37b10] [c000000007c37b50] 0xc000000007c37b50 (unreliable)
> [ 8.809045] [c000000007c37b50] [c0000000009ee674] scsi_device_put+0x44/0x70
> [ 8.809053] [c000000007c37b80] [c000000000a10c70] alua_rtpg_work+0x210/0x920
> [ 8.809059] [c000000007c37c90] [c000000000182314] process_one_work+0x2b4/0x5b0
> [ 8.809066] [c000000007c37d30] [c000000000182688] worker_thread+0x78/0x600
> [ 8.809072] [c000000007c37dc0] [c00000000018f4f4] kthread+0x124/0x130
> [ 8.809079] [c000000007c37e10] [c00000000000cffc] ret_from_kernel_thread+0x5c/0x64
> [ 8.809086] Instruction dump:
> [ 8.809090] f821ffc1 41820034 395e03c0 7c0004ac 7d205028 2c090001 3929ffff 41c00010
> [ 8.809101] 7d20512d
> [ 8.809101] sd 1:0:0:1: [sdc] Preferred minimum I/O size 32768 bytes
> [ 8.809102] 40c2ffec 7c0004ac 79290fe2 <0b090000> 60000000 38210040 ebc1fff0
> [ 8.809115] ---[ end trace 0000000000000000 ]—
>
> -next-20221108 was good. Git bisect points to following
>
> commit 0b25e17e9018a0ea68a9f0b4787672e8c68fa8d5
> Date: Mon Oct 31 15:47:25 2022 -0700
> scsi: alua: Move a scsi_device_put() call out of alua_check_vpd()
>
> Reverting this patch gets rid of the warning.

Hi Sachin,

Thanks for the detailed report. Does the patch below help?

diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c
index 693cd827e138..d2cf15338724 100644
--- a/drivers/scsi/device_handler/scsi_dh_alua.c
+++ b/drivers/scsi/device_handler/scsi_dh_alua.c
@@ -1025,7 +1025,7 @@ static bool __must_check alua_rtpg_queue(struct alua_port_group *pg,
kref_put(&pg->kref, release_port_group);
}

- return true;
+ return sdev != NULL;
}

/*


2022-11-11 05:18:12

by Sachin Sant

[permalink] [raw]
Subject: Re: [6.1.0-rc4-next-20221109] Boot time warning kernel/module/main.c:852

>> [ 8.809079] [c000000007c37e10] [c00000000000cffc] ret_from_kernel_thread+0x5c/0x64
>> [ 8.809086] Instruction dump:
>> [ 8.809090] f821ffc1 41820034 395e03c0 7c0004ac 7d205028 2c090001 3929ffff 41c00010
>> [ 8.809101] 7d20512d
>> [ 8.809101] sd 1:0:0:1: [sdc] Preferred minimum I/O size 32768 bytes
>> [ 8.809102] 40c2ffec 7c0004ac 79290fe2 <0b090000> 60000000 38210040 ebc1fff0
>> [ 8.809115] ---[ end trace 0000000000000000 ]—
>> -next-20221108 was good. Git bisect points to following
>> commit 0b25e17e9018a0ea68a9f0b4787672e8c68fa8d5
>> Date: Mon Oct 31 15:47:25 2022 -0700
>> scsi: alua: Move a scsi_device_put() call out of alua_check_vpd()
>> Reverting this patch gets rid of the warning.
>
> Hi Sachin,
>
> Thanks for the detailed report. Does the patch below help?
>

Yup, thanks. With this change applied I do not see the warning.

- Sachin

> diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c
> index 693cd827e138..d2cf15338724 100644
> --- a/drivers/scsi/device_handler/scsi_dh_alua.c
> +++ b/drivers/scsi/device_handler/scsi_dh_alua.c
> @@ -1025,7 +1025,7 @@ static bool __must_check alua_rtpg_queue(struct alua_port_group *pg,
> kref_put(&pg->kref, release_port_group);
> }
>
> - return true;
> + return sdev != NULL;
> }
>
> /*
>