Signed-off-by: Keno Fischer <keno@xxxxxxxxxxxxxxxxxx> --- man2/ptrace.2 | 34 +++++++++++++++++++++++++--------- 1 file changed, 25 insertions(+), 9 deletions(-) diff --git a/man2/ptrace.2 b/man2/ptrace.2 index 3a5ee65..cb1b976 100644 --- a/man2/ptrace.2 +++ b/man2/ptrace.2 @@ -737,7 +737,7 @@ is ignored.) For .BR PTRACE_SYSEMU , continue and stop on entry to the next system call, -which will not be executed. +which will not be executed. See the documentation on syscall-stops below. For .BR PTRACE_SYSEMU_SINGLESTEP , do the same but also singlestep if not a system call. @@ -1568,18 +1568,35 @@ set to .IR "(event<<8)\ |\ SIGTRAP" . .SS Syscall-stops If the tracee was restarted by -.BR PTRACE_SYSCALL , +.BR PTRACE_SYSCALL +or +.BR PTRACE_SYSEMU , the tracee enters -syscall-enter-stop just prior to entering any system call. -If the tracer restarts the tracee with +syscall-enter-stop just prior to entering any system call (which +will not be executed if the restart was using +.BR PTRACE_SYSEMU, +regardless of any change made to registers at this point or how the +tracee is restarted after this stop). +No matter which method caused the syscall-entry-stop, +if the tracer restarts the tracee with .BR PTRACE_SYSCALL , the tracee enters syscall-exit-stop when the system call is finished, or if it is interrupted by a signal. (That is, signal-delivery-stop never happens between syscall-enter-stop and syscall-exit-stop; it happens .I after -syscall-exit-stop.) -.LP +syscall-exit-stop.). If the tracee is continued using any other method +( +including +.BR PTRACE_SYSEMU +), no syscall-exit-stop occurs. Note that all mentions +.BR PTRACE_SYSEMU +apply equally to +.BR PTRACE_SYSEMU_SINGLESTEP. +.LP +However, even if the tracee is was continued using +.BR PTRACE_SYSCALL +, it is not guaranteed that the next stop will be a syscall-exit-stop. Other possibilities are that the tracee may stop in a .B PTRACE_EVENT stop, exit (if it entered @@ -1695,12 +1712,11 @@ set to .B SIGTRAP or .IR (SIGTRAP|0x80) . -.SS PTRACE_SINGLESTEP, PTRACE_SYSEMU, PTRACE_SYSEMU_SINGLESTEP stops +.SS PTRACE_SINGLESTEP stops [Details of these kinds of stops are yet to be documented.] .\" .\" FIXME . -.\" document stops occurring with PTRACE_SINGLESTEP, PTRACE_SYSEMU, -.\" PTRACE_SYSEMU_SINGLESTEP +.\" document stops occurring with PTRACE_SINGLESTEP .SS Informational and restarting ptrace commands Most ptrace commands (all except .BR PTRACE_ATTACH , -- 2.8.1 -- To unsubscribe from this list: send the line "unsubscribe linux-man" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
