Hi Lei Ming,

在 2018/11/27 21:08, Ming Lei 写道:

On Tue, Nov 27, 2018 at 05:55:45PM +0800, chenxiang (M) wrote:

quoted

Hi all,

There is a issue which may be related to CONFIG_SCSI_MQ_DEFAULT: before we
developed DIF/DIX feature on kernel 4.18 (disable CONFIG_SCSI_MQ_DEFAULT
default), and
it works well.

I guess you are testing hisi_sas_v3_hw, does 4.18 work with
'scsi_mod.use_blk_mq=Y'? If yes, you may run 'git bisect' to figure out
which commit is the 1st bad one.

quoted

But when we switch to kernel 4.19-rc1 and 4.20-rc1, Call
trace as follow occurs when running fio and if disable config
CONFIG_SCSI_MQ_DEFAULT,
then it works well. Also if switch ioengine=libaio to ioengine=psync, it
seems also work well. Do you have any idea or encounter similar issue?

I tested scsi-debug via 'dix=1 dif=1', looks everything is fine, are you
using direct io or not?

quoted

job1: (g=0): rw=rw, bs=4K-4K/4K-4K, ioengine=libaio, iodepth=128
job1: (g=0): rw=rw, bs=4K-4K/4K-4K, ioengine=libaio, iodepth=128
job1: (g=0): rw=rw, bs=4K-4K/4K-4K, ioengine=libaio, iodepth=128
job1: (g=0): rw=rw, bs=4K-4K/4K-4K, ioengine=libaio, iodepth=128
job1: (g=0): rw=rw, bs=4K-4K/4K-4K, ioengine=libaio, iodepth=128
job1: (g=0): rw=rw, bs=4K-4K/4K-4K, ioengine=libaio, iodepth=128
job1: (g=0): rw=rw, bs=4K-4K/4K-4K, ioengine=libaio, iodepth=128
job1: (g=0): rw=rw, bs=4K-4K/4K-4K, ioengine=libaio, iodepth=128
job1: (g=0): rw=rw, bs=4K-4K/4K-4K, ioengine=libaio, iodepth=128
job1: (g=0): rw=rw, bs=4K-4K/4K-4K, ioengine=libaio, iodepth=128
job1: (g=0): rw=rw, bs=4K-4K/4K-4K, ioengine=libaio, iodepth=128
job1: (g=0): rw=rw, bs=4K-4K/4K-4K, ioengine=libaio, iodepth=128
fio 2.0.5
Starting 12 processes
[  629.210506] Unable to handle kernel paging request at virtual address
0000ffff8027e048
[  629.210506] Unable to handle kernel paging request at virtual address
0000ffff8027e048
[  629.226373] Mem abort info:
[  629.226373] Mem abort info:
[  629.231952]   ESR = 0x96000006
[  629.231952]   ESR = 0x96000006
[  629.238052]   Exception class = DABT (current EL), IL = 32 bits
[  629.238052]   Exception class = DABT (current EL), IL = 32 bits
[  629.249898]   SET = 0, FnV = 0
[  629.249898]   SET = 0, FnV = 0
[  629.255998]   EA = 0, S1PTW = 0
[  629.255998]   EA = 0, S1PTW = 0
[  629.262272] Data abort info:
[  629.262272] Data abort info:
[  629.268023]   ISV = 0, ISS = 0x00000006
[  629.268023]   ISV = 0, ISS = 0x00000006
[  629.275690]   CM = 0, WnR = 0
[  629.275690]   CM = 0, WnR = 0
[  629.281617] user pgtable: 4k pages, 48-bit VAs, pgdp = 0000000085c91728
[  629.281617] user pgtable: 4k pages, 48-bit VAs, pgdp = 0000000085c91728
[  629.294857] [0000ffff8027e048] pgd=00000027a8644003,
pud=00000027a85ea003, pmd=0000000000000000
[  629.294857] [0000ffff8027e048] pgd=00000027a8644003,
pud=00000027a85ea003, pmd=0000000000000000
[  629.312278] Internal error: Oops: 96000006 [#1] PREEMPT SMP
[  629.312278] Internal error: Oops: 96000006 [#1] PREEMPT SMP
[  629.323427] Modules linked in: hisi_sas_v3_hw [last unloaded:
hisi_sas_v3_hw]
[  629.323427] Modules linked in: hisi_sas_v3_hw [last unloaded:
hisi_sas_v3_hw]
[  629.337713] CPU: 13 PID: 4465 Comm: fio Not tainted
4.20.0-rc1-15093-ge876dec #1067
[  629.337713] CPU: 13 PID: 4465 Comm: fio Not tainted
4.20.0-rc1-15093-ge876dec #1067
[  629.353040] Hardware name: Huawei D06/D06, BIOS Hisilicon D06 UEFI RC0 -
B601 (V6.01) 11/08/2018
[  629.353040] Hardware name: Huawei D06/D06, BIOS Hisilicon D06 UEFI RC0 -
B601 (V6.01) 11/08/2018
[  629.370633] pstate: 80400009 (Nzcv daif +PAN -UAO)
[  629.370633] pstate: 80400009 (Nzcv daif +PAN -UAO)
[  629.380218] pc : deadline_remove_request+0x2c/0xd0
[  629.380218] pc : deadline_remove_request+0x2c/0xd0

Could you use gdb to find where 'deadline_remove_request+0x2c' points
to?

 From objdump, 'deadline_remove_request+0x2c' is on the function 
__list_del  -> INIT_LIST_HEAD.

Thanks,
Ming

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