| Summary: | sdt.exp kprobe tests FAIL with SEGV | ||
|---|---|---|---|
| Product: | systemtap | Reporter: | Mark Wielaard <mark> |
| Component: | runtime | Assignee: | Josh Stone <jistone> |
| Status: | RESOLVED FIXED | ||
| Severity: | normal | CC: | jistone, scox |
| Priority: | P2 | ||
| Version: | unspecified | ||
| Target Milestone: | --- | ||
| Host: | Target: | ||
| Build: | Last reconfirmed: | ||
|
Description
Mark Wielaard
2010-03-06 15:46:44 UTC
The crash is in stap itself, has nothing to do with kernel (upgrade).
Program received signal SIGSEGV, Segmentation fault.
operator<< (o=..., t=...) at /home/mark/src/systemtap/parse.cxx:104
104 o << tt2str(t.type);
(gdb) bt
#0 operator<< (o=..., t=...) at /home/mark/src/systemtap/parse.cxx:104
#1 0x000000000047b2d2 in std::basic_string<char, std::char_traits<char>,
std::allocator<char> > lex_cast_qstring<token>(token const&) ()
#2 0x00000000004617f3 in c_unparser::record_actions (this=0x7fffffffbd20,
actions=<value optimized out>, tok=0x0, update=<value optimized out>)
at /home/mark/src/systemtap/translate.cxx:2332
#3 0x0000000000461c23 in c_unparser::visit_next_statement (
this=0x7fffffffbd20, s=0x23415e0)
at /home/mark/src/systemtap/translate.cxx:2874
#4 0x0000000000462513 in c_unparser::visit_if_statement (this=0x7fffffffbd20,
s=0x2341530) at /home/mark/src/systemtap/translate.cxx:2444
#5 0x0000000000457235 in c_unparser::visit_block (this=0x7fffffffbd20,
s=0x2341500) at /home/mark/src/systemtap/translate.cxx:2350
#6 0x0000000000464df4 in c_unparser::emit_probe (this=0x7fffffffbd20, v=
0x2335e80) at /home/mark/src/systemtap/translate.cxx:1702
#7 0x0000000000460732 in translate_pass (s=...)
at /home/mark/src/systemtap/translate.cxx:5418
#8 0x0000000000410012 in main (argc=<value optimized out>,
argv=<value optimized out>) at /home/mark/src/systemtap/main.cxx:1354
go up some frames and find a lex_cast_qstring(NULL) that triggers this (because
tok == NULL):
#2 0x00000000004617f3 in c_unparser::record_actions (this=0x7fffffffbd20,
actions=<value optimized out>, tok=0x0, update=<value optimized out>)
at /home/mark/src/systemtap/translate.cxx:2332
2332 o->newline() << "c->last_stmt = " << lex_cast_qstring(*tok) << ";";
(gdb) list
2327 if ((update && action_counter > 0) || action_counter >= 10/*<-arbitrary*/)
2328 {
2329 o->newline() << "c->actionremaining -= " << action_counter << ";";
2330 o->newline() << "if (unlikely (c->actionremaining <= 0)) {";
2331 o->newline(1) << "c->last_error = \"MAXACTION exceeded\";";
2332 o->newline() << "c->last_stmt = " << lex_cast_qstring(*tok) << ";";
2333 o->newline() << "goto out;";
2334 o->newline(-1) << "}";
2335 action_counter = 0;
2336 }
Introduced by:
commit 54975cd8f5844cca2cc0a32ab26fd2b546a81984
Author: Josh Stone <jistone@redhat.com>
Date: Fri Mar 5 17:24:41 2010 -0800
PR11342: Ensure that last_stmt is always set
* translate.cxx (c_unparser::record_actions): Take a token to fill in
last_stmt for MAXACTION errors.
(c_unparser::*): Pass a token to record_actions.
(c_unparser::visit_try_block): The try/catch blocks are also basic
blocks, so they should flush record_actions when done.
(c_unparser_assignment::c_assignop): Set last_stmt for /= and %=.
(c_unparser::visit_foreach_loop): Set last_stmt for agg. overflow.
(c_unparser::visit_print_format): Set last_stmt for %m errors.
We really should assert that ->tok is always set, which we sometimes have forgotten in manually synthesized elements. I've fixed those I found in SDT, but I also made record_actions lenient for now. commit 63ea4244cd378a756017c66085bdf45d4ce95df4 |