On 2023/9/17 17:10, Peter Zijlstra wrote:
On Sat, Sep 16, 2023 at 02:55:47PM +0800, Baokun Li wrote:
On 2023/9/13 16:59, Yi Zhang wrote:
The issue still can be reproduced on the latest linux tree[2].
To reproduce I need to run about 1000 times blktests block/001, and
bisect shows it was introduced with commit[1], as it was not 100%
reproduced, not sure if it's the culprit?
[1] 9257959a6e5b locking/atomic: scripts: restructure fallback ifdeffery
Hello, everyone！
We have confirmed that the merge-in of this patch caused hlist_bl_lock
(aka, bit_spin_lock) to fail, which in turn triggered the issue above.
[root@localhost ~]# insmod mymod.ko
[ 37.994787][ T621] >>> a = 725, b = 724
[ 37.995313][ T621] ------------[ cut here ]------------
[ 37.995951][ T621] kernel BUG at fs/mymod/mymod.c:42!
[r[ oo 3t7@.l996o4c61al]h[o s T6t21] ~ ]#Int ernal error: Oops - BUG:
00000000f2000800 [#1] SMP
[ 37.997420][ T621] Modules linked in: mymod(E)
[ 37.997891][ T621] CPU: 9 PID: 621 Comm: bl_lock_thread2 Tainted:
G E 6.4.0-rc2-00034-g9257959a6e5b-dirty #117
[ 37.999038][ T621] Hardware name: linux,dummy-virt (DT)
[ 37.999571][ T621] pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS
BTYPE=--)
[ 38.000344][ T621] pc : increase_ab+0xcc/0xe70 [mymod]
[ 38.000882][ T621] lr : increase_ab+0xcc/0xe70 [mymod]
[ 38.001416][ T621] sp : ffff800008b4be40
[ 38.001822][ T621] x29: ffff800008b4be40 x28: 0000000000000000 x27:
0000000000000000
[ 38.002605][ T621] x26: 0000000000000000 x25: 0000000000000000 x24:
0000000000000000
[ 38.003385][ T621] x23: ffffd9930c698190 x22: ffff800008a0ba38 x21:
0000000000000001
[ 38.004174][ T621] x20: ffffffffffffefff x19: ffffd9930c69a580 x18:
0000000000000000
[ 38.004955][ T621] x17: 0000000000000000 x16: ffffd9933011bd38 x15:
ffffffffffffffff
[ 38.005754][ T621] x14: 0000000000000000 x13: 205d313236542020 x12:
ffffd99332175b80
[ 38.006538][ T621] x11: 0000000000000003 x10: 0000000000000001 x9 :
ffffd9933022a9d8
[ 38.007325][ T621] x8 : 00000000000bffe8 x7 : c0000000ffff7fff x6 :
ffffd993320b5b40
[ 38.008124][ T621] x5 : ffff0001f7d1c708 x4 : 0000000000000000 x3 :
0000000000000000
[ 38.008912][ T621] x2 : 0000000000000000 x1 : 0000000000000000 x0 :
0000000000000015
[ 38.009709][ T621] Call trace:
[ 38.010035][ T621] increase_ab+0xcc/0xe70 [mymod]
[ 38.010539][ T621] kthread+0xdc/0xf0
[ 38.010927][ T621] ret_from_fork+0x10/0x20
[ 38.011370][ T621] Code: 17ffffe0 90000020 91044000 9400000d (d4210000)
[ 38.012067][ T621] ---[ end trace 0000000000000000 ]---
Is this arm64 or something? You seem to have forgotten to mention what
platform you're using.
Sorry for the late reply.
We tested both x86 and arm64, and the problem is only encountered under
arm64.
--
With Best Regards,
Baokun Li
.
