[commit] Unwinder for OpenBSD/sparc64 kernel trap frames

Mark Kettenis
2006-12-31T01:28:23Z

With this patch and a current OpenBSD/sparc64 I can actually debug
kernel core dump files.

Committed,

Mark

Index: ChangeLog
from Mark Kettenis <kettenis@gnu.org>

* sparc64-tdep.h (SPARC64_PSTATE_AG, SPARC64_PSTATE_IE)
(SPARC64_PSTATE_PRIV, SPARC64_PSTATE_AM, SPARC64_PSTATE_PEF)
(SPARC64_PSTATE_RED, SPARC64_PSTATE_TLE, SPARC64_PSTATE_CLE)
(SPARC64_PSTATE_PID0, SPARC64_PSTATE_PID1): New defines.
* sparc64nbsd-nat.c: Include "gdbcore.h".
(sparc64nbsd_supply_pcb): Get %pc from stack if necessary. Supply
processor state register.
* sparc64obsd-tdep.c (sparc64obsd_trapframe_cache)
(sparc64obsd_trapframe_this_id)
(sparc64obsd_trapframe_prev_register)
(sparc64obsd_trapframe_sniffer): New functions.
(sparc64obsd_trapframe_unwind): New variable.
(sparc64obsd_init_abi): Append trapframe unwinder.
* Makefile.in (sparc64nbsd-nat.o): Update dependencies.

Index: Makefile.in
===================================================================
RCS file: /cvs/src/src/gdb/Makefile.in,v
retrieving revision 1.861
diff -u -p -r1.861 Makefile.in
--- Makefile.in 17 Dec 2006 13:30:43 -0000 1.861
+++ Makefile.in 31 Dec 2006 00:42:58 -0000
@@ -2676,8 +2676,8 @@ sparc64-linux-tdep.o: sparc64-linux-tdep
$(trad_frame_h) $(tramp_frame_h) $(sparc64_tdep_h)
sparc64-nat.o: sparc64-nat.c $(defs_h) $(gdbarch_h) $(sparc64_tdep_h) \
$(sparc_nat_h)
-sparc64nbsd-nat.o: sparc64nbsd-nat.c $(defs_h) $(regcache_h) $(target_h) \
- $(sparc64_tdep_h) $(sparc_nat_h) $(bsd_kvm_h)
+sparc64nbsd-nat.o: sparc64nbsd-nat.c $(defs_h) $(gdbcore_h) $(regcache_h) \
+ $(target_h) $(sparc64_tdep_h) $(sparc_nat_h) $(bsd_kvm_h)
sparc64nbsd-tdep.o: sparc64nbsd-tdep.c $(defs_h) $(frame_h) \
$(frame_unwind_h) $(gdbcore_h) $(osabi_h) $(regcache_h) $(regset_h) \
$(symtab_h) $(objfiles_h) $(solib_svr4_h) $(trad_frame_h) \
Index: sparc64-tdep.h
===================================================================
RCS file: /cvs/src/src/gdb/sparc64-tdep.h,v
retrieving revision 1.6
diff -u -p -r1.6 sparc64-tdep.h
--- sparc64-tdep.h 17 Dec 2005 22:34:02 -0000 1.6
+++ sparc64-tdep.h 31 Dec 2006 00:42:58 -0000
@@ -1,6 +1,6 @@
/* Target-dependent code for UltraSPARC.

- Copyright (C) 2003, 2004 Free Software Foundation, Inc.
+ Copyright (C) 2003, 2004, 2006 Free Software Foundation, Inc.

This file is part of GDB.

@@ -84,6 +84,18 @@ enum sparc64_regnum
= SPARC64_Q0_REGNUM + 15
};

+/* Processor state bits. */
+#define SPARC64_PSTATE_AG 0x001
+#define SPARC64_PSTATE_IE 0x002
+#define SPARC64_PSTATE_PRIV 0x004
+#define SPARC64_PSTATE_AM 0x008
+#define SPARC64_PSTATE_PEF 0x010
+#define SPARC64_PSTATE_RED 0x020
+#define SPARC64_PSTATE_TLE 0x100
+#define SPARC64_PSTATE_CLE 0x200
+#define SPARC64_PSTATE_PID0 0x400
+#define SPARC64_PSTATE_PID1 0x800
+
extern void sparc64_init_abi (struct gdbarch_info info,
struct gdbarch *gdbarch);

Index: sparc64nbsd-nat.c
===================================================================
RCS file: /cvs/src/src/gdb/sparc64nbsd-nat.c,v
retrieving revision 1.7
diff -u -p -r1.7 sparc64nbsd-nat.c
--- sparc64nbsd-nat.c 17 Dec 2005 22:34:02 -0000 1.7
+++ sparc64nbsd-nat.c 31 Dec 2006 00:42:58 -0000
@@ -1,6 +1,6 @@
/* Native-dependent code for NetBSD/sparc64.

- Copyright (C) 2003, 2004 Free Software Foundation, Inc.
+ Copyright (C) 2003, 2004, 2006 Free Software Foundation, Inc.

This file is part of GDB.

@@ -20,6 +20,7 @@
Boston, MA 02110-1301, USA. */

#include "defs.h"
+#include "gdbcore.h"
#include "regcache.h"
#include "target.h"

@@ -136,6 +137,7 @@ sparc64nbsd_fpregset_supplies_p (int reg
static int
sparc64nbsd_supply_pcb (struct regcache *regcache, struct pcb *pcb)
{
+ u_int64_t state;
int regnum;

/* The following is true for NetBSD 1.6.2:
@@ -148,9 +150,19 @@ sparc64nbsd_supply_pcb (struct regcache
if (pcb->pcb_sp == 0)
return 0;

+ /* If the program counter is zero, this is probably a core dump, and
+ we can get %pc from the stack. */
+ if (pcb->pcb_pc == 0)
+ read_memory(pcb->pcb_sp + BIAS - 176 + (11 * 8),
+ (gdb_byte *)&pcb->pcb_pc, sizeof pcb->pcb_pc);
+
+
regcache_raw_supply (regcache, SPARC_SP_REGNUM, &pcb->pcb_sp);
regcache_raw_supply (regcache, SPARC64_PC_REGNUM, &pcb->pcb_pc);

+ state = pcb->pcb_pstate << 8 | pcb->pcb_cwp;
+ regcache_raw_supply (regcache, SPARC64_STATE_REGNUM, &state);
+
sparc_supply_rwindow (regcache, pcb->pcb_sp, -1);

return 1;
Index: sparc64obsd-tdep.c
===================================================================
RCS file: /cvs/src/src/gdb/sparc64obsd-tdep.c,v
retrieving revision 1.19
diff -u -p -r1.19 sparc64obsd-tdep.c
--- sparc64obsd-tdep.c 22 Jan 2006 20:07:38 -0000 1.19
+++ sparc64obsd-tdep.c 31 Dec 2006 00:42:58 -0000
@@ -202,6 +202,86 @@ sparc64obsd_sigtramp_frame_sniffer (stru
return NULL;
}
\f
+/* Kernel debugging support. */
+
+static struct sparc_frame_cache *
+sparc64obsd_trapframe_cache(struct frame_info *next_frame, void **this_cache)
+{
+ struct sparc_frame_cache *cache;
+ CORE_ADDR sp, trapframe_addr;
+ int regnum;
+
+ if (*this_cache)
+ return *this_cache;
+
+ cache = sparc_frame_cache (next_frame, this_cache);
+ gdb_assert (cache == *this_cache);
+
+ sp = frame_unwind_register_unsigned (next_frame, SPARC_SP_REGNUM);
+ trapframe_addr = sp + BIAS + 176;
+
+ cache->saved_regs = trad_frame_alloc_saved_regs (next_frame);
+
+ cache->saved_regs[SPARC64_STATE_REGNUM].addr = trapframe_addr;
+ cache->saved_regs[SPARC64_PC_REGNUM].addr = trapframe_addr + 8;
+ cache->saved_regs[SPARC64_NPC_REGNUM].addr = trapframe_addr + 16;
+
+ for (regnum = SPARC_G0_REGNUM; regnum <= SPARC_I7_REGNUM; regnum++)
+ cache->saved_regs[regnum].addr =
+ trapframe_addr + 48 + (regnum - SPARC_G0_REGNUM) * 8;
+
+ return cache;
+}
+
+static void
+sparc64obsd_trapframe_this_id (struct frame_info *next_frame,
+ void **this_cache, struct frame_id *this_id)
+{
+ struct sparc_frame_cache *cache =
+ sparc64obsd_trapframe_cache (next_frame, this_cache);
+
+ (*this_id) = frame_id_build (cache->base, cache->pc);
+}
+
+static void
+sparc64obsd_trapframe_prev_register (struct frame_info *next_frame,
+ void **this_cache,
+ int regnum, int *optimizedp,
+ enum lval_type *lvalp, CORE_ADDR *addrp,
+ int *realnump, gdb_byte *valuep)
+{
+ struct sparc_frame_cache *cache =
+ sparc64obsd_trapframe_cache (next_frame, this_cache);
+
+ trad_frame_get_prev_register (next_frame, cache->saved_regs, regnum,
+ optimizedp, lvalp, addrp, realnump, valuep);
+}
+
+static const struct frame_unwind sparc64obsd_trapframe_unwind =
+{
+ NORMAL_FRAME,
+ sparc64obsd_trapframe_this_id,
+ sparc64obsd_trapframe_prev_register
+};
+
+static const struct frame_unwind *
+sparc64obsd_trapframe_sniffer (struct frame_info *next_frame)
+{
+ ULONGEST pstate;
+ char *name;
+
+ /* Check whether we are in privileged mode, and bail out if we're not. */
+ pstate = frame_unwind_register_unsigned(next_frame, SPARC64_PSTATE_REGNUM);
+ if ((pstate & SPARC64_PSTATE_PRIV) == 0)
+ return NULL;
+
+ find_pc_partial_function (frame_pc_unwind (next_frame), &name, NULL, NULL);
+ if (name && strcmp (name, "Lslowtrap_reenter") == 0)
+ return &sparc64obsd_trapframe_unwind;
+
+ return NULL;
+}
+\f

/* Threads support. */

@@ -299,6 +379,7 @@ sparc64obsd_init_abi (struct gdbarch_inf
tdep->step_trap = sparcnbsd_step_trap;

frame_unwind_append_sniffer (gdbarch, sparc64obsd_sigtramp_frame_sniffer);
+ frame_unwind_append_sniffer (gdbarch, sparc64obsd_trapframe_sniffer);

sparc64_init_abi (info, gdbarch);