From Bugzilla Helper: User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.7.10) Gecko/20050720 Fedora/1.0.6-1.1.fc4 Firefox/1.0.6 Description of problem: When using the PTRACE_SETIOPTIONS function of ptrace() and setting the PTRACE_O_TRACEEXIT flag, the register values the debugger sees reported by the kernel for the child process are bogus when hitting the "about to exit" SIGTRAP. I suspect no one saved the registers in the user area ptrace looks for them in, they appear to be some random previous register set value leftover from the last actual save. I will attach the exitbug2.c program and exitbug2.results file demonstrating the problem. Version-Release number of selected component (if applicable): kernel-2.6.9-5.EL How reproducible: Always Steps to Reproduce: 1. gcc -o exitbug2 -g exitbug2.c 2. ./exitbug2 3. observe the obviously bad rsp register value in final reg dump. Actual Results: rsp=0x0000007fbfffee80 while I know for a fact that a previously existing stack frame had a value somewhere around 0x7fbfffec60, since the _exit call is the last frame on the stack, the rsp value should be decremented from 0x7fbfffec60, not incremented :-). Expected Results: The rsp= value should be <= the last entry in the level:4 printout at the end of the program. Additional info: This is a problem because debuggers can't tell the user who the heck called exit (which may be relevant to the bug they are trying to find). The walkback is all messaed up because the registers are bad.
Created attachment 117466 [details] test program to demo bug
Created attachment 117467 [details] results from test run showing error
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