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1.194. strace

1.194.1. RHBA-2010:0047: bug fix update

Note

This update has already been released (prior to the GA of this release) as errata RHBA-2010:0047
An updated strace package that fixes a bug when tracing a program that blocks the SIGTRAP signal is now available.
The strace program intercepts and records the system calls called and received by a running process. Strace can print a record of each system call, its arguments and its return value.
This updated strace package fixes the following bug:
* the kernel does not send SIGTRAP notifications to strace after an execve system call finishes. Consequently, when "strace -f" was executed against a program that blocked the SIGTRAP signal and subsequently called execve, strace sent a "[preattached child 0 of 12166 in weird state!]" message to STD OUT and hung. With this update, strace now checks for this situation and re-synchronizes with system call notifications when necessary. Note: this problem only presents on Itanium-based systems (BZ#548363)
All strace users are advised to upgrade to this updated package, which resolves this issue.

1.194.2. RHBA-2010:0174: bug fix update

Note

This update has already been released (prior to the GA of this release) as errata RHBA-2010:0174
An updated strace package that fixes two bugs is now available.
The strace program intercepts and records the system calls called and received by a running process. Strace can print a record of each system call, its arguments and its return value.
This updated strace package fixes the following bugs:
* when an strace process was terminated by a signal while the tracee was executing a fork or clone system call the tracee was forcefully terminated instead of being cleanly detached. This update corrects this: tracees are now cleanly detached as expected when an strace process is terminated in the circumstance noted above. (BZ#558471)
* RHBA-2010:0047, the strace update released to address BZ#548363, uncovered a race condition on Itanium-based systems. (See References below for a link to this previous release.) The race condition presented when strace attached to a process while said process was executing the execve system call. With this update, strace now reliably detects this post-execve trap and, consequently, avoids the race condition. (BZ#564364)

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