Greeting, FYI, we noticed the following commit (built with clang-13): commit: 6dafca97803309c3cb5148d449bfa711e41ddef2 ("x86, build: use objtool mcount") https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git master in testcase: trinity version: trinity-x86_64-4d2343bd-1_20210105 with following parameters: group: ["group-00", "group-01", "group-02", "group-03", "group-04"] test-description: Trinity is a linux system call fuzz tester. test-url: http://codemonkey.org.uk/projects/trinity/ 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): +---------------------------------------------------------+------------+------------+ | | 22c8542d7b | 6dafca9780 | +---------------------------------------------------------+------------+------------+ | WARNING:at_arch/x86/kernel/ftrace.c:#ftrace_verify_code | 0 | 18 | | RIP:ftrace_verify_code | 0 | 18 | | WARNING:at_kernel/trace/ftrace.c:#ftrace_bug | 0 | 18 | | RIP:ftrace_bug | 0 | 18 | +---------------------------------------------------------+------------+------------+ If you fix the issue, kindly add following tag Reported-by: kernel test robot [ 4.743393] WARNING: CPU: 0 PID: 1 at arch/x86/kernel/ftrace.c:96 ftrace_verify_code (kbuild/src/consumer/arch/x86/kernel/ftrace.c:96) [ 4.744022] Modules linked in: [ 4.744254] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.11.0-rc2-00022-g6dafca978033 #2 [ 4.744827] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 [ 4.745423] RIP: 0010:ftrace_verify_code (kbuild/src/consumer/arch/x86/kernel/ftrace.c:96) [ 4.745776] Code: 03 33 03 8a 4c 24 07 32 4b 04 0f b6 c9 09 c1 74 41 48 c7 c7 a0 30 22 83 be 01 00 00 00 31 d2 b9 01 00 00 00 e8 4e 23 1b 00 90 <0f> 0b 90 bb ea ff ff ff 48 c7 c7 d0 30 22 83 be 01 00 00 00 31 d2 All code ======== 0: 03 33 add (%rbx),%esi 2: 03 8a 4c 24 07 32 add 0x3207244c(%rdx),%ecx 8: 4b 04 0f rex.WXB add $0xf,%al b: b6 c9 mov $0xc9,%dh d: 09 c1 or %eax,%ecx f: 74 41 je 0x52 11: 48 c7 c7 a0 30 22 83 mov $0xffffffff832230a0,%rdi 18: be 01 00 00 00 mov $0x1,%esi 1d: 31 d2 xor %edx,%edx 1f: b9 01 00 00 00 mov $0x1,%ecx 24: e8 4e 23 1b 00 callq 0x1b2377 29: 90 nop 2a:* 0f 0b ud2 <-- trapping instruction 2c: 90 nop 2d: bb ea ff ff ff mov $0xffffffea,%ebx 32: 48 c7 c7 d0 30 22 83 mov $0xffffffff832230d0,%rdi 39: be 01 00 00 00 mov $0x1,%esi 3e: 31 d2 xor %edx,%edx Code starting with the faulting instruction =========================================== 0: 0f 0b ud2 2: 90 nop 3: bb ea ff ff ff mov $0xffffffea,%ebx 8: 48 c7 c7 d0 30 22 83 mov $0xffffffff832230d0,%rdi f: be 01 00 00 00 mov $0x1,%esi 14: 31 d2 xor %edx,%edx [ 4.747093] RSP: 0000:ffff8881003cbb50 EFLAGS: 00010202 [ 4.747472] RAX: 0000000066227969 RBX: ffffffff82204214 RCX: 0000000000000001 [ 4.748050] RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffffffff832230b8 [ 4.748568] RBP: 0000000000000001 R08: 00000000a0000002 R09: 0000000040000000 [ 4.749081] R10: 0000000000000001 R11: 0000000080000000 R12: 0000000000000000 [ 4.749594] R13: 00000000009aa301 R14: 0000000000000001 R15: ffff88810009f9f0 [ 4.750110] FS: 0000000000000000(0000) GS:ffff88823fa00000(0000) knlGS:0000000000000000 [ 4.750690] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 4.751110] CR2: 0000000000000000 CR3: 0000000002c12000 CR4: 00000000000406b0 [ 4.751625] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 4.752145] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 4.752659] Call Trace: [ 4.754727] ftrace_replace_code (kbuild/src/consumer/arch/x86/kernel/ftrace.c:220) [ 4.755046] ftrace_modify_all_code (kbuild/src/consumer/kernel/trace/ftrace.c:2691) [ 4.755378] ftrace_run_update_code (kbuild/src/consumer/kernel/trace/ftrace.c:2770) [ 4.755709] ftrace_startup (kbuild/src/consumer/kernel/trace/ftrace.c:2897) [ 4.755997] register_ftrace_function (kbuild/src/consumer/kernel/trace/ftrace.c:7516) [ 4.756335] arm_kprobe_ftrace (kbuild/src/consumer/kernel/kprobes.c:1049 kbuild/src/consumer/kernel/kprobes.c:1071) [ 4.756631] enable_kprobe (kbuild/src/consumer/kernel/kprobes.c:2189) [ 4.756904] enable_trace_kprobe (kbuild/src/consumer/kernel/trace/trace_kprobe.c:381) [ 4.757220] __ftrace_event_enable_disable (kbuild/src/consumer/kernel/trace/trace_events.c:457) [ 4.757605] __ftrace_set_clr_event_nolock (kbuild/src/consumer/kernel/trace/trace_events.c:818) [ 4.758002] trace_array_set_clr_event (kbuild/src/consumer/kernel/trace/trace_events.c:833 kbuild/src/consumer/kernel/trace/trace_events.c:924) [ 4.758352] test_gen_kprobe_cmd (kbuild/src/consumer/kernel/trace/kprobe_event_gen_test.c:95) [ 4.758676] ? kprobe_event_cmd_init (kbuild/src/consumer/kernel/trace/trace_kprobe.c:924) [ 4.759007] ? init_trace_printk (kbuild/src/consumer/kernel/trace/kprobe_event_gen_test.c:176) [ 4.759310] kprobe_event_gen_test_init (kbuild/src/consumer/kernel/trace/kprobe_event_gen_test.c:179) [ 4.759654] do_one_initcall (kbuild/src/consumer/init/main.c:1217) [ 4.759947] ? native_sched_clock (kbuild/src/consumer/arch/x86/kernel/tsc.c:243) [ 4.760272] ? sched_clock_cpu (kbuild/src/consumer/kernel/sched/clock.c:273 kbuild/src/consumer/kernel/sched/clock.c:382) [ 4.760571] ? pvclock_clocksource_read (kbuild/src/consumer/arch/x86/kernel/pvclock.c:80) [ 4.760927] ? __fs_reclaim_release (kbuild/src/consumer/mm/page_alloc.c:4328) [ 4.761248] ? kvm_sched_clock_read (kbuild/src/consumer/arch/x86/include/asm/preempt.h:84 kbuild/src/consumer/arch/x86/kernel/kvmclock.c:90 kbuild/src/consumer/arch/x86/kernel/kvmclock.c:101) [ 4.761571] ? sched_clock (kbuild/src/consumer/arch/x86/include/asm/paravirt.h:22 kbuild/src/consumer/arch/x86/kernel/tsc.c:252) [ 4.761834] ? sched_clock_cpu (kbuild/src/consumer/kernel/sched/clock.c:273 kbuild/src/consumer/kernel/sched/clock.c:382) [ 4.762138] ? parse_args (kbuild/src/consumer/kernel/params.c:153 kbuild/src/consumer/kernel/params.c:188) [ 4.762432] do_initcall_level (kbuild/src/consumer/init/main.c:1289) [ 4.762730] do_initcalls (kbuild/src/consumer/init/main.c:1303) [ 4.763019] ? rest_init (kbuild/src/consumer/init/main.c:1412) [ 4.763291] kernel_init_freeable (kbuild/src/consumer/init/main.c:1534) [ 4.763601] kernel_init (kbuild/src/consumer/init/main.c:1417) [ 4.763864] ret_from_fork (kbuild/src/consumer/arch/x86/entry/entry_64.S:302) [ 4.764159] ---[ end trace cde667a4bb4795ca ]--- [ 4.764496] ------------[ ftrace bug ]------------ [ 4.764847] ftrace failed to modify [ 4.764852] do_sys_open (kbuild/src/consumer/fs/open.c:1186) [ 4.765483] actual: 0f:1f:44:00:00 [ 4.765784] Setting ftrace call site to call ftrace function [ 4.766193] ftrace record flags: 50000001 [ 4.766490] (1) R [ 4.766490] expected tramp: ffffffff81037af0 [ 4.766959] ------------[ cut here ]------------ To reproduce: # build kernel cd linux cp config-5.11.0-rc2-00022-g6dafca978033 .config make HOSTCC=clang-13 CC=clang-13 ARCH=x86_64 olddefconfig prepare modules_prepare bzImage git clone https://github.com/intel/lkp-tests.git cd lkp-tests bin/lkp qemu -k job-script # job-script is attached in this email Thanks, Oliver Sang