Hi, Thanks for the reply. Let me have one following question. As my understand, in SKAS mode, tracer and tracee are different host processes, and they have UML kernel code and application code respectively. (in TT mode, tracee has both kernel and application code)
Suppose the tracee attmpts to invoke a host system call. then, it will be intercepted by the tracer as in TT mode. (In TT mode, the tracer turns off tracing and sends SIGUSR2 to the tracee, and then, the signal handler in the tracee will execute the system call.) but, in SKAS mode, because the tracee doesn't have the UML kernel code, only the tracer knows about the system call code. The tracer cannot simply send a signal to make the tracee execute the system call. Then how does it do? Does the tracer execute the system call for the tracee? Thank you, > > In SKAS mode, instead, the UML scheduler switches back and forth between > various "processes" (inside UML) which are all running inside userspace, and > ptrace the various host threads (actually collapsed into one userspace > thread, thanks to SKAS mode) which run only the real userspace code. So the > ptraced context always executes userspace code and we never turn ptracing > off. > -- > Paolo Giarrusso, aka Blaisorblade > Skype user "PaoloGiarrusso" > Linux registered user n. 292729 > http://www.user-mode-linux.org/~blaisorblade > > ------------------------------------------------------- This SF.Net email is sponsored by Oracle Space Sweepstakes Want to be the first software developer in space? Enter now for the Oracle Space Sweepstakes! http://ads.osdn.com/?ad_idt12&alloc_id344&op=click _______________________________________________ User-mode-linux-devel mailing list User-mode-linux-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/user-mode-linux-devel
