On 01/26/2012 12:59 AM, Jamie Lokier wrote: > Tracers mainly want to know if it's a 32-bit or 64-bit syscall, not > whether it's compat as such. Another idea, avoiding new PTRACE_EVENTs per arch, would be to make the abi32/abi64/compat/whatnot discriminator retrievable with PTRACE_GETEVENTMSG instead. So you'd get PTRACE_EVENT_SYSCALL_ENTRY|EXIT, or the regular old 0x80|SIGTRAP, you'd still fetch the syscall number from $orig_ax (or whatever means for other archs), as usual, then have extra syscall info in PTRACE_GETEVENTMSG. I don't know if it'd be simple to make it possible to do PTRACE_GETEVENTMSG on a 0x80|SIGTRAP trap, but I imagine it so. -> wait <- 0x80|SIGTRAP (or PTRACE_EVENT_SYSCALL_ENTRY) -> read regs, find out syscall number -> PTRACE_GETEVENTMSG, figure out which entry mode was used. -- Pedro Alves -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
