PATCH: Add ia32 support to x32 strace

[H.J. Lu]

On Wed, Apr 18, 2012 at 9:09 AM, Dmitry V. Levin <ldv at altlinux.org> wrote:
> On Tue, Apr 17, 2012 at 05:39:28PM -0700, H.J. Lu wrote:
>> On Tue, Apr 17, 2012 at 5:13 PM, Dmitry V. Levin <ldv at altlinux.org> wrote:
>> > On Tue, Apr 17, 2012 at 05:03:20PM -0700, H.J. Lu wrote:
>> >> On Tue, Apr 17, 2012 at 4:58 PM, Dmitry V. Levin <ldv at altlinux.org> wrote:
>> >> > On Tue, Apr 17, 2012 at 11:05:04AM -0700, H.J. Lu wrote:
>> >> >> Hi,
>> >> >>
>> >> >> This patch adds ia32 support to x32 strace.  Tested on Linux/x32.
>> >> > [...]
>> >> >> @@ -868,15 +874,14 @@ get_scno(struct tcb *tcp)
>> >> >>       }
>> >> >>  # endif
>> >> >>  # ifdef X32
>> >> >> -     if (currpers == 0 || currpers == 1) {
>> >> >> -             fprintf(stderr, "syscall_%lu (...) in unsupported %s "
>> >> >> -                     "mode of process PID=%d\n", scno,
>> >> >> -                     currpers == 0 ? "64-bit" : "32-bit", tcp->pid);
>> >> >> +     if (currpers == 0) {
>> >> >> +             fprintf(stderr, "syscall_%lu (...) in unsupported 64-bit "
>> >> >> +                     "mode of process PID=%d\n", scno, tcp->pid);
>> >> >>               return 0;
>> >> >>       }
>> >> >> -# else
>> >> >> -     update_personality(tcp, currpers);
>> >> >> +     else if (currpers == 1)
>> >> >>  # endif
>> >> >> +     update_personality(tcp, currpers);
>> >> >>  #elif defined(IA64)
>> >> >>  #    define IA64_PSR_IS      ((long)1 << 34)
>> >> >>       if (upeek(tcp, PT_CR_IPSR, &psr) >= 0)
>> >> >
>> >> > This part of the change seems to be wrong: if strace supports two personalities
>> >> > on X32, it should be able to switch to any of them, not just to
>> >> > currpers == 1.  Looks like additional currpers translation is needed for
>> >> > the X32 case.
>> >>
>> >> currpers is set the same value for both x32 and x86-64 strace,
>> >>
>> >> 0: x86-64
>> >> 1: ia32
>> >> 2. x32
>> >>
>> >> For x32 strace, when currpers == 1, we call update_personality to update
>> >> personality.  When currpers == 2, we do nothing since the current
>> >> personality is x32.
>> >
>> > We have to handle the case when currpers == 2 and current_personality == 1.
>> > Supposing that currpers == 2 on X32 translates to current_personality == 0,
>> > we have to call update_personality(tcp, 0) in that case.
>> >
>>
>> Here is the updated patch to set currpers == 0 for x32.
>
> Converted those two "if" statements to a "switch" and applied.  Thanks.
>
>

Thanks.


-- 
H.J.