4.5.0+ panic when setup loop device

From: Xiong Zhou
Date: Wed Mar 16 2016 - 02:48:43 EST


hi,

This panic was not found on 4.5 final kernel. Now it is reproducible
till commit 710d60cbf .

bisect point to :
commit 1f12e32f4cd5243ae46d8b933181be0d022c6793
Author: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Date: Mon Feb 22 22:19:15 2016 +0000

x86/topology: Create logical package id


It showed on next-20150302 tree firstly, bisect between 0301 tree and
0302 tree went nowhere..
Now it is reproducible on Linus tree.

steps:
fallocate -l 1G test.img
loopdev=$(losetup --find --show test.img)


full log , bisect log and config are attached.

Thanks,
Xiong


[ 503.302458] loop: module loaded
[ 503.322815] BUG: unable to handle kernel paging request at ffffe8f8fca41a14
[ 503.363966] IP: [<ffffffff81340887>] kobject_init+0x17/0x90
[ 503.396755] PGD bbf22067 PUD bbf21067 PMD bbf20067 PTE 0
[ 503.428178] Oops: 0000 [#1] SMP
[ 503.447951] Modules linked in: loop kvm_amd kvm irqbypass
crct10dif_pclmul crc32_pclmul ghash_clmulni_intel aesni_intel lrw
gf128mul ipmi_ssif glue_helper ablk_helper sg amd64_edac_mod nfsd
pcspkr hpilo cryptd ipmi_si edac_mce_amd hpwdt sp5100_tco
ipmi_msghandler edac_core fam15h_power shpchp i2c_piix4 k10temp
acpi_power_meter acpi_cpufreq auth_rpcgss nfs_acl lockd grace sunrpc
ip_tables xfs libcrc32c sd_mod radeon i2c_algo_bit drm_kms_helper
syscopyarea sysfillrect sysimgblt fb_sys_fops ttm ata_generic
pata_acpi ahci drm libahci pata_atiixp hpsa libata crc32c_intel
i2c_core nd_pmem serio_raw bnx2 scsi_transport_sas dm_mirror
dm_region_hash dm_log dm_mod
[ 503.788265] CPU: 13 PID: 12511 Comm: losetup Not tainted 4.5.0-rc6+ #78
[ 503.827285] Hardware name: HP ProLiant DL385 G7, BIOS A18 03/19/2012
[ 503.865452] task: ffff880132fb8000 ti: ffff88083a210000 task.ti:
ffff88083a210000
[ 503.909812] RIP: 0010:[<ffffffff81340887>] [<ffffffff81340887>]
kobject_init+0x17/0x90
[ 503.958992] RSP: 0018:ffff88083a213d28 EFLAGS: 00010282
[ 503.990539] RAX: ffffe8f8fca41900 RBX: ffffe8f8fca419d8 RCX: 0000000000000001
[ 504.033492] RDX: 0000000000000020 RSI: ffffffff81adb040 RDI: ffffe8f8fca419d8
[ 504.075306] RBP: ffff88083a213d38 R08: 0000000000000000 R09: ffffffff813401be
[ 504.115608] R10: ffff88013bb5a400 R11: ffffea0020d61a00 R12: ffffffff81adb040
[ 504.155965] R13: ffff8800ac4f85c8 R14: ffff880836ef8800 R15: ffff880836ef8880
[ 504.195840] FS: 00007ff685dbb740(0000) GS:ffff88013bb40000(0000)
knlGS:0000000000000000
[ 504.241973] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 504.275430] CR2: ffffe8f8fca41a14 CR3: 0000000133a1d000 CR4: 00000000000406e0
[ 504.314203] Stack:
[ 504.325542] 0000000000000001 ffff8800ac4f8000 ffff88083a213d70
ffffffff81320296
[ 504.366429] ffff8800ac4f8000 ffff880836ef8800 ffff880836ef8870
ffff8800ac4f8588
[ 504.410991] ffff880836ef8880 ffff88083a213db0 ffffffff813157d4
ffff880836ef8880
[ 504.455541] Call Trace:
[ 504.469999] [<ffffffff81320296>] blk_mq_register_disk+0xa6/0x160
[ 504.505490] [<ffffffff813157d4>] blk_register_queue+0xb4/0x160
[ 504.540521] [<ffffffff813230fd>] add_disk+0x1dd/0x4a0
[ 504.570938] [<ffffffffa0516f70>] loop_add+0x1f0/0x270 [loop]
[ 504.604979] [<ffffffffa0517222>] loop_control_ioctl+0x112/0x160 [loop]
[ 504.644763] [<ffffffff81226986>] do_vfs_ioctl+0xa6/0x5c0
[ 504.674226] [<ffffffff81226f19>] SyS_ioctl+0x79/0x90
[ 504.702882] [<ffffffff816bb9ee>] entry_SYSCALL_64_fastpath+0x12/0x71
[ 504.737751] Code: e5 ff d0 5d c3 48 c7 c0 fb ff ff ff c3 0f 1f 80
00 00 00 00 55 48 85 ff 48 89 e5 41 54 53 48 89 fb 74 37 48 85 f6 49
89 f4 74 66 <f6> 47 3c 01 75 48 48 8d 43 08 c7 43 38 01 00 00 00 4c 89
63 28
[ 504.843245] RIP [<ffffffff81340887>] kobject_init+0x17/0x90
[ 504.875091] RSP <ffff88083a213d28>
[ 504.894984] CR2: ffffe8f8fca41a14
[ 504.914017] ---[ end trace 1afddf59bf08cc38 ]---

Attachment: looppanic
Description: Binary data