0eae81dc9f
Prohibit probing on IRQ handlers in irqentry_text because if it interrupts user mode, at that point we haven't changed to kernel space yet and which eventually leads a double fault. E.g. # echo p apic_timer_interrupt > kprobe_events # echo 1 > events/kprobes/enable PANIC: double fault, error_code: 0x0 CPU: 1 PID: 814 Comm: less Not tainted 4.20.0-rc3+ #30 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996) RIP: 0010:error_entry+0x12/0xf0 [snip] Call Trace: <ENTRY_TRAMPOLINE> ? native_iret+0x7/0x7 ? async_page_fault+0x8/0x30 ? trace_hardirqs_on_thunk+0x1c/0x1c ? error_entry+0x7c/0xf0 ? async_page_fault+0x8/0x30 ? native_iret+0x7/0x7 ? int3+0xa/0x20 ? trace_hardirqs_on_thunk+0x1c/0x1c ? error_entry+0x7c/0xf0 ? int3+0xa/0x20 ? apic_timer_interrupt+0x1/0x20 </ENTRY_TRAMPOLINE> Kernel panic - not syncing: Machine halted. Kernel Offset: disabled ---[ end Kernel panic - not syncing: Machine halted. ]--- Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andrea Righi <righi.andrea@gmail.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/154998796400.31052.8406236614820687840.stgit@devbox Signed-off-by: Ingo Molnar <mingo@kernel.org>