Hi, https://lore.kernel.org/lkml/20190320221534.165ab...@oasis.local.home/ didn't get merged. And the crash it was trying to fix still happens on the latest master branch. If rebasing the patch on the latest top, the following new crash come up.
Sometimes, root@intel-x86-64:~# echo 1 > /sys/kernel/debug/tracing/options/userstacktrace root@intel-x86-64:~# echo 1 > /sys/kernel/debug/tracing/events/preemptirq/irq_disable/enable root@intel-x86-64:~# echo 1 > /proc/sys/kernel/stack_tracer_enabled hangs... Sometimes, root@intel-x86-64:~# echo 1 > /sys/kernel/debug/tracing/options/userstacktrace root@intel-x86-64:~# echo 1 > /sys/kernel/debug/tracing/events/preemptirq/irq_disable/enable root@intel-x86-64:~# echo 1 > /proc/sys/kernel/stack_tracer_enabled PANIC: double fault, error_code: 0x0 CPU: 0 PID: 492 Comm: sh Not tainted 5.2.0-rc2 #1 Hardware name: Intel Corporation Broadwell Client platform/Basking Ridge, BIOS BDW-E2R1.86C.0118.R01.1503110618 03/11/2015 RIP: 0010:error_entry+0x32/0x100 Code: 89 7c 24 08 52 31 d2 51 31 c9 50 41 50 45 31 c0 41 51 45 31 c9 41 52 45 31 d2 41 53 45 31 db 53 31 db 55 31 ed 41 54 45 31 e4 <41> 55 45 31 ed 41 56 45 31 f6 41 57 45 31 ff 56 48 8d 6c 24 09 f6 RSP: 0018:ffff9ab680000000 EFLAGS: 00010046 RAX: 00000000ae200a97 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffffae200ec9 RDI: ffffffffae201176 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 00007f2c078a4740(0000) GS:ffff988fb8a00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffff9ab67ffffff8 CR3: 000000005b8ee003 CR4: 00000000003606f0 Call Trace: <IRQ> ? native_iret+0x7/0x7 ? int3+0x29/0x40 ? error_entry+0x86/0x100 ? trace_hardirqs_off_caller_cr2+0x1/0x20 ? trace_hardirqs_off_caller_cr2+0x1/0x20 ? trace_hardirqs_off_thunk_cr2+0x1a/0x1c ? native_iret+0x7/0x7 ? int3+0x29/0x40 ? error_entry+0x86/0x100 ? error_entry+0x86/0x100 ? int3+0x29/0x40 ? native_iret+0x7/0x7 ? int3+0x29/0x40 ? error_entry+0x86/0x100 ? trace_hardirqs_off_caller_cr2+0x1/0x20 ? trace_hardirqs_off_caller_cr2+0x1/0x20 ? trace_hardirqs_off_thunk_cr2+0x1a/0x1c ? native_iret+0x7/0x7 ? int3+0x29/0x40 ? error_entry+0x86/0x100 ? error_entry+0x86/0x100 ? int3+0x29/0x40 ? native_iret+0x7/0x7 ? int3+0x29/0x40 ? error_entry+0x86/0x100 ? trace_hardirqs_off_caller_cr2+0x1/0x20 ? trace_hardirqs_off_caller_cr2+0x1/0x20 ? trace_hardirqs_off_thunk_cr2+0x1a/0x1c ? native_iret+0x7/0x7 ? int3+0x29/0x40 ? error_entry+0x86/0x100 ? error_entry+0x86/0x100 ? int3+0x29/0x40 ? native_iret+0x7/0x7 ? int3+0x29/0x40 ? error_entry+0x86/0x100 ? trace_hardirqs_off_caller_cr2+0x1/0x20 ? trace_hardirqs_off_caller_cr2+0x1/0x20 ? trace_hardirqs_off_thunk_cr2+0x1a/0x1c ? native_iret+0x7/0x7 ? int3+0x29/0x40 ? error_entry+0x86/0x100 ? error_entry+0x86/0x100 ? int3+0x29/0x40 ? native_iret+0x7/0x7 ? int3+0x29/0x40 ? error_entry+0x86/0x100 ? trace_hardirqs_off_caller_cr2+0x1/0x20 ? trace_hardirqs_off_caller_cr2+0x1/0x20 ? trace_hardirqs_off_thunk_cr2+0x1a/0x1c ? native_iret+0x7/0x7 ? int3+0x29/0x40 ? error_entry+0x86/0x100 ? error_entry+0x86/0x100 ? int3+0x29/0x40 ? native_iret+0x7/0x7 ? int3+0x29/0x40 ? error_entry+0x86/0x100 ? trace_hardirqs_off_caller_cr2+0x1/0x20 ? trace_hardirqs_off_caller_cr2+0x1/0x20 ? trace_hardirqs_off_thunk_cr2+0x1a/0x1c ? native_iret+0x7/0x7 ? int3+0x29/0x40 ? error_entry+0x86/0x100 ? error_entry+0x86/0x100 ? int3+0x29/0x40 ? native_iret+0x7/0x7 ? int3+0x29/0x40 ? error_entry+0x86/0x100 ? trace_hardirqs_off_caller_cr2+0x1/0x20 ? trace_hardirqs_off_caller_cr2+0x1/0x20 ? trace_hardirqs_off_thunk_cr2+0x1a/0x1c ? native_iret+0x7/0x7 ? int3+0x29/0x40 ? error_entry+0x86/0x100 ? error_entry+0x86/0x100 ? int3+0x29/0x40 ? native_iret+0x7/0x7 ? int3+0x29/0x40 ? error_entry+0x86/0x100 ? trace_hardirqs_off_caller_cr2+0x1/0x20 ? trace_hardirqs_off_caller_cr2+0x1/0x20 ? trace_hardirqs_off_thunk_cr2+0x1a/0x1c ? native_iret+0x7/0x7 ? int3+0x29/0x40 ? error_entry+0x86/0x100 ? error_entry+0x86/0x100 ? int3+0x29/0x40 ? native_iret+0x7/0x7 ? int3+0x29/0x40 ? error_entry+0x86/0x100 ? trace_hardirqs_off_caller_cr2+0x1/0x20 ? trace_hardirqs_off_caller_cr2+0x1/0x20 ? trace_hardirqs_off_thunk_cr2+0x1a/0x1c ? native_iret+0x7/0x7 ? int3+0x29/0x40 ? error_entry+0x86/0x100 ? error_entry+0x86/0x100 ? int3+0x29/0x40 ? native_iret+0x7/0x7 ? int3+0x29/0x40 ? error_entry+0x86/0x100 ? trace_hardirqs_off_caller_cr2+0x1/0x20 ? trace_hardirqs_off_caller_cr2+0x1/0x20 ? trace_hardirqs_off_thunk_cr2+0x1a/0x1c ? native_iret+0x7/0x7 ? int3+0x29/0x40 ? error_entry+0x86/0x100 ? error_entry+0x86/0x100 ? int3+0x29/0x40 ? native_iret+0x7/0x7 ? int3+0x29/0x40 ? error_entry+0x86/0x100 ? trace_hardirqs_off_caller_cr2+0x1/0x20 ? trace_hardirqs_off_caller_cr2+0x1/0x20 ? trace_hardirqs_off_thunk_cr2+0x1a/0x1c ? native_iret+0x7/0x7 ? int3+0x29/0x40 ? error_entry+0x86/0x100 ? error_entry+0x86/0x100 ? int3+0x29/0x40 ? native_iret+0x7/0x7 ? int3+0x29/0x40 ? error_entry+0x86/0x100 ? trace_hardirqs_off_caller_cr2+0x1/0x20 ? trace_hardirqs_off_caller_cr2+0x1/0x20 ? trace_hardirqs_off_thunk_cr2+0x1a/0x1c ? native_iret+0x7/0x7 ? int3+0x29/0x40 ? error_entry+0x86/0x100 ? error_entry+0x86/0x100 ? int3+0x29/0x40 ? native_iret+0x7/0x7 ? int3+0x29/0x40 ? error_entry+0x86/0x100 ? trace_hardirqs_off_caller_cr2+0x1/0x20 ? trace_hardirqs_off_caller_cr2+0x1/0x20 ? trace_hardirqs_off_thunk_cr2+0x1a/0x1c ? native_iret+0x7/0x7 ? int3+0x29/0x40 ? error_entry+0x86/0x100 ? error_entry+0x86/0x100 ? int3+0x29/0x40 ? native_iret+0x7/0x7 ? int3+0x29/0x40 ? error_entry+0x86/0x100 ? trace_hardirqs_off_caller_cr2+0x1/0x20 ? trace_hardirqs_off_caller_cr2+0x1/0x20 ? trace_hardirqs_off_thunk_cr2+0x1a/0x1c ? native_iret+0x7/0x7 ? int3+0x29/0x40 ? error_entry+0x86/0x100 ? error_entry+0x86/0x100 ? int3+0x29/0x40 ? native_iret+0x7/0x7 ? int3+0x29/0x40 ? error_entry+0x86/0x100 ? trace_hardirqs_off_caller_cr2+0x1/0x20 ? trace_hardirqs_off_caller_cr2+0x1/0x20 ? trace_hardirqs_off_thunk_cr2+0x1a/0x1c ? native_iret+0x7/0x7 ? int3+0x29/0x40 ? error_entry+0x86/0x100 ? error_entry+0x86/0x100 ? int3+0x29/0x40 ? native_iret+0x7/0x7 ? int3+0x29/0x40 ? error_entry+0x86/0x100 ? trace_hardirqs_off_caller_cr2+0x1/0x20 ? trace_hardirqs_off_caller_cr2+0x1/0x20 ? trace_hardirqs_off_thunk_cr2+0x1a/0x1c ? native_iret+0x7/0x7 ? int3+0x29/0x40 ? error_entry+0x86/0x100 ? error_entry+0x86/0x100 ? int3+0x29/0x40 ? native_iret+0x7/0x7
