Greeting,

FYI, we noticed the following commit (built with gcc-9):

commit: 738b8a92befe6011b8c766e40aa1fbd26ada2695 ("[PATCH v2 3/3] dyndbg: fix problem parsing format="foo bar"")
url: https://github.com/0day-ci/linux/commits/Jim-Cromie/dynamic-debug-fixups-for-5-9/20200826-022923
base: https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git 6a9dc5fd6170d0a41c8a14eb19e63d94bea5705a

in testcase: kernel-selftests
with following parameters:

	group: kselftests-livepatch

test-description: The kernel contains a set of "self tests" under the tools/testing/selftests/ directory. These are intended to be small unit tests to exercise individual code paths in the kernel.
test-url: https://www.kernel.org/doc/Documentation/kselftest.txt


on test machine: qemu-system-x86_64 -enable-kvm -cpu SandyBridge -smp 2 -m 8G

caused below changes (please refer to attached dmesg/kmsg for entire log/backtrace):


+------------------------------------------+------------+------------+
|                                          | 6ed59ab9d5 | 738b8a92be |
+------------------------------------------+------------+------------+
| boot_successes                           | 4          | 0          |
| boot_failures                            | 0          | 4          |
| kernel_BUG_at_lib/dynamic_debug.c        | 0          | 4          |
| invalid_opcode:#[##]                     | 0          | 4          |
| RIP:ddebug_exec_query                    | 0          | 4          |
| Kernel_panic-not_syncing:Fatal_exception | 0          | 4          |
+------------------------------------------+------------+------------+


If you fix the issue, kindly add following tag
Reported-by: kernel test robot <lkp@intel.com>


[   53.159074] kernel BUG at lib/dynamic_debug.c:267!
[   53.163121] invalid opcode: 0000 [#1] PREEMPT SMP PTI
[   53.164809] CPU: 1 PID: 1077 Comm: test-livepatch. Tainted: G              K   5.9.0-rc2-00045-g738b8a92befe6 #1
[   53.167382] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014
[   53.168793] RIP: 0010:ddebug_exec_query+0x676/0x760
[   53.169904] Code: 0f 85 73 08 00 00 4c 89 7c 24 28 e9 2d fc ff ff 4c 89 fe 48 8d 7c 24 10 e8 b7 f8 ff ff 85 c0 0f 84 18 fc ff ff e9 cf 07 00 00 <0f> 0b 8b 15 3a 7b e2 02 85 d2 0f 85 c6 00 00 00 45 31 e4 48 c7 c6
[   53.172910] RSP: 0018:ffffaac6c0e7bd78 EFLAGS: 00010246
[   53.174112] RAX: 000000000000003d RBX: ffff8d1c51300c2c RCX: 0000000000000000
[   53.175451] RDX: 000000000000003d RSI: ffff8d1c51300c28 RDI: ffff8d1c51300c2c
[   53.176814] RBP: 0000000000000004 R08: ffff8d1c51300c2e R09: 0000000000000000
[   53.178156] R10: ffff8d1c488530c0 R11: ffff8d1c48853e08 R12: 0000000000000004
[   53.179496] R13: 0000000000000004 R14: 0000000000000000 R15: 0000000000000000
[   53.180877] FS:  00007f1c428ac740(0000) GS:ffff8d1d37d00000(0000) knlGS:0000000000000000
[   53.182310] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   53.183559] CR2: 0000000000442d70 CR3: 0000000165d2a000 CR4: 00000000000406e0
[   53.186445] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   53.187822] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   53.189151] Call Trace:
[   53.190147]  ddebug_exec_queries+0x6a/0x100
[   53.191251]  ddebug_proc_write+0x4e/0x80
[   53.192355]  full_proxy_write+0x56/0x80
[   53.193421]  vfs_write+0xec/0x240
[   53.194431]  ksys_write+0x68/0xe0
[   53.195431]  do_syscall_64+0x33/0x40
[   53.196462]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[   53.197592] RIP: 0033:0x7f1c42999504
[   53.198621] Code: 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b3 0f 1f 80 00 00 00 00 48 8d 05 f9 61 0d 00 8b 00 85 c0 75 13 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 54 c3 0f 1f 00 41 54 49 89 d4 55 48 89 f5 53
[   53.201660] RSP: 002b:00007fff0d6b6208 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
[   53.203057] RAX: ffffffffffffffda RBX: 00000000000000bc RCX: 00007f1c42999504
[   53.204444] RDX: 00000000000000bc RSI: 0000564b7e8061d0 RDI: 0000000000000001
[   53.205818] RBP: 0000564b7e8061d0 R08: fffffffffffffff0 R09: 00007f1c42a29e80
[   53.207197] R10: 0000564b7e80628c R11: 0000000000000246 R12: 00007f1c42a6b760
[   53.208575] R13: 00000000000000bc R14: 00007f1c42a66760 R15: 00000000000000bc
[   53.209950] Modules linked in: sr_mod cdrom sg snd_pcm intel_rapl_msr ata_generic pata_acpi ppdev ata_piix libata intel_rapl_common crct10dif_pclmul snd_timer crc32_pclmul snd crc32c_intel ghash_clmulni_intel aesni_intel crypto_simd bochs_drm drm_vram_helper cryptd drm_ttm_helper glue_helper joydev soundcore ttm pcspkr serio_raw i2c_piix4 parport_pc ipmi_devintf ipmi_msghandler floppy parport ip_tables [last unloaded: test_klp_atomic_replace]
[   53.217827] ---[ end trace 32d22997ab7e3c2a ]---


To reproduce:

        # build kernel
	cd linux
	cp config-5.9.0-rc2-00045-g738b8a92befe6 .config
	make HOSTCC=gcc-9 CC=gcc-9 ARCH=x86_64 olddefconfig prepare modules_prepare bzImage

        git clone https://github.com/intel/lkp-tests.git
        cd lkp-tests
        bin/lkp qemu -k <bzImage> job-script # job-script is attached in this email



Thanks,
lkp