[lkml]   [2008]   [Apr]   [21]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [Bug 10489] Kprobe smoke test lockdep warning
Thank you for reporting.

Actually, kprobes tries to fixup thread's flags in post_kprobe_handler
(which is called from kprobe_exceptions_notify) by
trace_hardirqs_fixup_flags(pt_regs->flags). However, even the irq flag
is set in pt_regs->flags, true hardirq is still off until returning
from do_debug. Thus, lockdep assumes that hardirq is off without annotation.

IMHO, one possible solution is that fixing hardirq flags right after
notify_die in do_debug instead of in post_kprobe_handler.


Masami Hiramatsu

Software Engineer
Hitachi Computer Products (America) Inc.
Software Solutions Division


 \ /
  Last update: 2008-04-22 00:57    [W:0.064 / U:1.340 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site