Re: [patch 15/21] ptrace changes

From: Martin Schwidefsky
Date: Wed Nov 05 2008 - 06:48:33 EST


On Mon, 2008-11-03 at 11:14 -0600, David Smith wrote:

> Is this correct, or should the 1st syscall argument be found in
> regs->orig_gpr2 by syscall_get_arguments()/syscall_set_arguments()?

The question is when do syscall_get_arguments and syscall_set_arguments
functions get called? If they are called on a call chain that started
from do_syscall_trace_enter then we'd have to use orig_gpr2 instead of
gprs[2] but if the functions are not called via do_syscall_trace_enter
the first argument is located in grprs[2]. As far as I can see the sole
user of syscall_get_arguments is collect_syscall which is used to get
the registers of a blocked process. In this case the kernel call chain
does not include do_syscall_trace_enter, therefore the first argument is
in gprs[2], no?

--
blue skies,
Martin.

"Reality continues to ruin my life." - Calvin.


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