BUG: soft lockup in kvm_vm

BUG: soft lockup in kvm_vm_ioctl
Status: upstream: reported syz repro on 2019/05/01 14:36
Reported-by: syzbot+8d9bb6157e7b379f740e@syzkaller.appspotmail.com
First crash: 903d, last: 791d

Cause bisection: introduced by (bisect log) :
commit 252153ba518ac0bcde6b7152c63380d4415bfe5d
Author: Eric Biggers <ebiggers@google.com>
Date: Wed Nov 29 20:43:17 2017 +0000

ubifs: switch to fscrypt_prepare_setattr()

Crash: INFO: rcu detected stall in corrupted (log)
Repro: syz .config

Fix bisection: fixed by (bisect log) :
commit 8b515be512a2435bb8aedc6390cbe140167f9eb9
Author: Farhan Ali <alifm@linux.ibm.com>
Date: Thu Jul 11 14:28:52 2019 +0000

vfio-ccw: Fix memory leak and don't call cp_free in cp_init

Sample crash report:

watchdog: BUG: soft lockup - CPU#0 stuck for 123s! [syz-executor.3:22023]
Modules linked in:
irq event stamp: 26556
hardirqs last  enabled at (26555): [<ffffffff81006673>] trace_hardirqs_on_thunk+0x1a/0x1c
hardirqs last disabled at (26556): [<ffffffff8100668f>] trace_hardirqs_off_thunk+0x1a/0x1c
softirqs last  enabled at (596): [<ffffffff87400662>] __do_softirq+0x662/0x95a kernel/softirq.c:320
softirqs last disabled at (517): [<ffffffff8144e4e0>] invoke_softirq kernel/softirq.c:374 [inline]
softirqs last disabled at (517): [<ffffffff8144e4e0>] irq_exit+0x180/0x1d0 kernel/softirq.c:414
CPU: 0 PID: 22023 Comm: syz-executor.3 Not tainted 5.1.0-rc6+ #89
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:csd_lock_wait kernel/smp.c:108 [inline]
RIP: 0010:smp_call_function_single+0x13e/0x420 kernel/smp.c:302
Code: 00 48 8b 4c 24 08 48 8b 54 24 10 48 8d 74 24 40 8b 7c 24 1c e8 23 fa ff ff 41 89 c5 eb 07 e8 e9 87 0a 00 f3 90 44 8b 64 24 58 <31> ff 41 83 e4 01 44 89 e6 e8 54 89 0a 00 45 85 e4 75 e1 e8 ca 87
RSP: 0018:ffff88809277f3e0 EFLAGS: 00000293 ORIG_RAX: ffffffffffffff13
RAX: ffff8880a8bfc040 RBX: 1ffff110124efe80 RCX: ffffffff8166051c
RDX: 0000000000000000 RSI: ffffffff81660507 RDI: 0000000000000005
RBP: ffff88809277f4b8 R08: ffff8880a8bfc040 R09: ffffed1015d25be9
R10: ffffed1015d25be8 R11: ffff8880ae92df47 R12: 0000000000000003
R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000000
FS:  00007fd569980700(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd56997e178 CR3: 00000000a4fd2000 CR4: 00000000001426f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 smp_call_function_many+0x750/0x8c0 kernel/smp.c:434
 smp_call_function+0x42/0x90 kernel/smp.c:492
 on_each_cpu+0x31/0x200 kernel/smp.c:602
 text_poke_bp+0x107/0x19b arch/x86/kernel/alternative.c:821
 __jump_label_transform+0x263/0x330 arch/x86/kernel/jump_label.c:91
 arch_jump_label_transform+0x2b/0x40 arch/x86/kernel/jump_label.c:99
 __jump_label_update+0x16a/0x210 kernel/jump_label.c:389
 jump_label_update kernel/jump_label.c:752 [inline]
 jump_label_update+0x1ce/0x3d0 kernel/jump_label.c:731
 static_key_slow_inc_cpuslocked+0x1c1/0x250 kernel/jump_label.c:129
 static_key_slow_inc+0x1b/0x30 kernel/jump_label.c:144
 kvm_arch_vcpu_init+0x6b7/0x870 arch/x86/kvm/x86.c:9068
 kvm_vcpu_init+0x272/0x370 arch/x86/kvm/../../../virt/kvm/kvm_main.c:320
 vmx_create_vcpu+0x191/0x2540 arch/x86/kvm/vmx/vmx.c:6577
 kvm_arch_vcpu_create+0x80/0x120 arch/x86/kvm/x86.c:8755
 kvm_vm_ioctl_create_vcpu arch/x86/kvm/../../../virt/kvm/kvm_main.c:2569 [inline]
 kvm_vm_ioctl+0x5ce/0x19c0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3105
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:509 [inline]
 do_vfs_ioctl+0xd6e/0x1390 fs/ioctl.c:696
 ksys_ioctl+0xab/0xd0 fs/ioctl.c:713
 __do_sys_ioctl fs/ioctl.c:720 [inline]
 __se_sys_ioctl fs/ioctl.c:718 [inline]
 __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:718
 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x458da9
Code: ad b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fd56997fc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000458da9
RDX: 0000000000000000 RSI: 000000000000ae41 RDI: 0000000000000005
RBP: 000000000073bfa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fd5699806d4
R13: 00000000004c1905 R14: 00000000004d40d0 R15: 00000000ffffffff
Sending NMI from CPU 0 to CPUs 1:

Crashes (2):
Manager	Time	Kernel	Commit	Syzkaller	Config	Log	Report	Syz repro	C repro	VM info	Title
ci-upstream-kasan-gce	2019/04/27 13:30	upstream	baf76f0c58ae	b617407b	.config	log	report	syz
ci-upstream-kasan-gce	2019/08/17 11:28	upstream	6e625a1a3f47	8fd428a1	.config	log	report