Hi Stephane, On Tue July 10 2007 8:02 am, Stephane Eranian wrote: > > 2) If we know for certain that a user-space tool always ptrace's the > > monitored process before making any of the effected Perfmon system-calls, > > then the ptrace_check_attach() call in the kernel should always be > > successful. In this case, could the call to ptrace_check_attach() be > > removed without altering the overall behavior? Obviously this isn't the > > real solution, but it might be a temporary workaround. > > Remember that this is a kernel API. We cannot assume tools are > well-behaved. There may be bugs and we need to prevent any malicious usage.
Yes, obviously that's not something you'd want to change in the actual Perfmon patches. I'm simply asking, for the purposes of testing my own kernel and tools, if I know that the tool is making the ptrace() calls in the appropriate places, are the kernel calls to ptrace_check_attach() still necessary? Or does removing those calls change the behavior of the Perfmon system-calls in some other way? Thanks, -- Kevin Corry [EMAIL PROTECTED] http://www.ibm.com/linux/ _______________________________________________ perfmon mailing list [email protected] http://www.hpl.hp.com/hosted/linux/mail-archives/perfmon/
