Bug 91085
Summary: | strace hangs and gives bad info for NPTL fork() | ||
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Product: | [Retired] Red Hat Linux | Reporter: | John Reiser <jreiser> |
Component: | strace | Assignee: | Roland McGrath <roland> |
Status: | CLOSED RAWHIDE | QA Contact: | Brian Brock <bbrock> |
Severity: | medium | Docs Contact: | |
Priority: | medium | ||
Version: | 9 | CC: | ofudd |
Target Milestone: | --- | ||
Target Release: | --- | ||
Hardware: | i686 | ||
OS: | Linux | ||
Whiteboard: | |||
Fixed In Version: | Doc Type: | Bug Fix | |
Doc Text: | Story Points: | --- | |
Clone Of: | Environment: | ||
Last Closed: | 2003-06-04 18:58:20 UTC | Type: | --- |
Regression: | --- | Mount Type: | --- |
Documentation: | --- | CRM: | |
Verified Versions: | Category: | --- | |
oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
Cloudforms Team: | --- | Target Upstream Version: | |
Embargoed: |
Description
John Reiser
2003-05-17 16:00:32 UTC
I did not see the hanging failure mode, but the bug corrupts syscall arguments and so a variety of failure modes are possible. I've found and fixed the bug in the upstream strace sources. There will be an errata version as soon as possible. Perhaps this is why 'strace -fp <pid>' is failing for me: # ps aux | grep httpd # strace -fp 9627 trace: ptrace(PTRACE_SYSCALL, ...): Operation not permitted detach: ptrace(PTRACE_DETACH, ...): Operation not permitted redhat 9, strace-4.4.95-2, default 2.4.20-8 kernel, updated httpd-2.0.40-21.1 That's very possible. Using strace on strace would show you the PIDs it uses in the ptrace calls that fail. If it is using bogus PID values, then that is probably the same bug. Something I discovered was that if I do strace -fp <pid>, and if I get that error, the process in question is put into 'T' state in a ps listing. Traced or stopped, according to the man page. Something *really* neat occurred when I tried 'strace -fo/tmp/a strace -fp <pid>' (or somesuch)... that httpd process is not only in 'T' state, but it's unkillable, even with a kill -9. Did you say there was a new rpm for strace available somewhere? There is a new strace version now available in rawhide. There will be an errata release for RHL9 at some point as well. |