Re: [PATCH][SPARC64] Fix breakpointing in syscalls other than sigreturn

[Mark Kettenis <mark.kettenis@xs4all.nl>]

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> Sender: gdb-patches-owner@sourceware.org
> 
> ping.  Could someone please take a look to this patch?  Thanks.

Diff looks reasonable to me, but I'm not really familliar with Linux'
system call interface on SPARC.  Best to make sure David S. Miller
takes a look at this.

> From: jose.marchesi@oracle.com (Jose E. Marchesi)
> To: gdb-patches@sourceware.org
> Subject: [PATCH][SPARC64] Fix breakpointing in syscalls other than sigreturn
> Date: Tue, 10 Sep 2013 20:29:33 +0200
> 
> Hi.
> 
> This small patch makes sparc64_linux_step_trap to return 0 when a
> breakpoint is set in a `ta 0x6d' which is not a sigreturn syscall.  In
> these cases no rt_frame exists in the stack and thus the read PC is
> wrong.
> 
> 2013-09-10  Jose E. Marchesi  <jose.marchesi@oracle.com>
> 
> 	* sparc64-linux-tdep.c (sparc64_linux_step_trap): Make sure the
> 	trap is a sigreturn syscall.
> 
> Index: gdb/sparc64-linux-tdep.c
> ===================================================================
> RCS file: /cvs/src/src/gdb/sparc64-linux-tdep.c,v
> retrieving revision 1.31
> diff -u -r1.31 sparc64-linux-tdep.c
> --- gdb/sparc64-linux-tdep.c	1 Jan 2013 06:32:51 -0000	1.31
> +++ gdb/sparc64-linux-tdep.c	10 Sep 2013 18:17:25 -0000
> @@ -111,7 +111,9 @@
>  static CORE_ADDR
>  sparc64_linux_step_trap (struct frame_info *frame, unsigned long insn)
>  {
> -  if (insn == 0x91d0206d)
> +  /* __NR_rt_sigreturn is 101  */
> +  if ((insn == 0x91d0206d)
> +      && (get_frame_register_unsigned (frame, SPARC_G1_REGNUM) == 101))
>      {
>        struct gdbarch *gdbarch = get_frame_arch (frame);
>        enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
> 
>