Description of problem: If you take the following program: #include <stdio.h> #include <stdlib.h> #include <sys/syscall.h> #include <sys/types.h> int main() { int foo; foo = syscall(289); fprintf(stderr, "Error is %d\n",foo); return 0; } and compile and run it on the RHEL 5.2 xen kernel, you will get -1 as the output from the syscall, since 289 is not a valid syscall in RHEL-5. Now, if you take that same program and run it under strace, you will get a return value of 289, which is wrong. This is because of a minor bug in arch/x86_64/kernel/entry-xen.S, where if we are tracing the syscall, we copy that syscall number into the return instead of the appropriate -ENOSYS. This bug is also present in the upstream Xen 2.6.18 kernel, but is fixed in the upstream Linux kernel.
Oh, I should mention that this came out of the discussion of BZ 442352, although I do not believe it is the root cause of that issue. Chris Lalancette
This request was evaluated by Red Hat Product Management for inclusion in a Red Hat Enterprise Linux maintenance release. Product Management has requested further review of this request by Red Hat Engineering, for potential inclusion in a Red Hat Enterprise Linux Update release for currently deployed products. This request is not yet committed for inclusion in an Update release.
in kernel-2.6.18-98.el5 You can download this test kernel from http://people.redhat.com/dzickus/el5
*** Bug 459442 has been marked as a duplicate of this bug. ***
*** Bug 461349 has been marked as a duplicate of this bug. ***
An advisory has been issued which should help the problem described in this bug report. This report is therefore being closed with a resolution of ERRATA. For more information on therefore solution and/or where to find the updated files, please follow the link below. You may reopen this bug report if the solution does not work for you. http://rhn.redhat.com/errata/RHSA-2009-0225.html