================================================================== BUG: KMSAN: uninit-value in update_stack_state+0x673/0xa40 arch/x86/kernel/unwind_frame.c:222 CPU: 1 PID: 6120 Comm: syz-executor4 Not tainted 4.16.0+ #84 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x185/0x1d0 lib/dump_stack.c:53 kmsan_report+0x142/0x240 mm/kmsan/kmsan.c:1067 __msan_warning_32+0x6c/0xb0 mm/kmsan/kmsan_instr.c:676 update_stack_state+0x673/0xa40 arch/x86/kernel/unwind_frame.c:222 unwind_next_frame+0x618/0xe50 arch/x86/kernel/unwind_frame.c:329 __save_stack_trace+0x6d9/0xa80 arch/x86/kernel/stacktrace.c:44 save_stack_trace_tsk+0x258/0x2f0 arch/x86/kernel/stacktrace.c:76 proc_pid_stack+0x26a/0x470 fs/proc/base.c:446 proc_single_show+0x1af/0x300 fs/proc/base.c:747 seq_read+0xc7d/0x2260 fs/seq_file.c:237 do_loop_readv_writev fs/read_write.c:673 [inline] do_iter_read+0x880/0xd70 fs/read_write.c:897 vfs_readv fs/read_write.c:959 [inline] do_preadv+0x3a1/0x580 fs/read_write.c:1043 SYSC_preadv+0xc6/0xe0 fs/read_write.c:1093 SyS_preadv+0x77/0xa0 fs/read_write.c:1088 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x3d/0xa2 RIP: 0033:0x455329 RSP: 002b:00007f00d1948c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000127 RAX: ffffffffffffffda RBX: 00007f00d19496d4 RCX: 0000000000455329 RDX: 0000000000000001 RSI: 0000000020000040 RDI: 0000000000000013 RBP: 000000000072bf58 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 000000000000046f R14: 00000000006f9b08 R15: 0000000000000001 Local variable description: ----flags.i.i.i@rcu_all_qs Variable was created at: rcu_all_qs+0x32/0x1f0 kernel/rcu/tree.c:478 _cond_resched+0x3c/0xd0 kernel/sched/core.c:4935 ==================================================================