Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6: (23 commits)
  sparc: sunzilog uart order
  [SPARC64]: Detect trap frames in stack backtraces.
  [SPARC64]: %l6 trap return handling no longer necessary.
  [SPARC64]: Use trap type stored in pt_regs to handle syscall restart.
  [SPARC64]: Store magic cookie and trap type in pt_regs.
  [SPARC64]: PROM debug console can be CON_ANYTIME.
  sparc64: cleanup after SunOS/Solaris binary emulation removal
  sparc: cleanup after SunOS binary emulation removal
  [SPARC64]: Add NUMA support.
  [SPARC64]: Allocate TSB node-local.
  [SPARC64]: NUMA device infrastructure.
  [SPARC64]: Kill pci_iommu_table_init() declaration.
  [SPARC64]: Once we have the boot cmdline, call parse_early_param()
  [SPARC64]: Remove unused asm-sparc64/numnodes.h
  [SPARC64]: Decrease SECTION_SIZE_BITS to 30.
  [SPARC64]: Initialize MDESC earlier and use lmb_alloc()
  [SPARC64]: Use lmb_alloc() for PROM device tree.
  [SPARC64]: Call real_setup_per_cpu_areas() earlier and use lmb_alloc().
  [SPARC64]: Fully use LMB information in bootmem_init().
  [SPARC64]: Start using LMB information in bootmem_init().
  ...

1 files changed, 16 insertions, 2 deletions

diff --git a/include/asm-sparc64/ptrace.h b/include/asm-sparc64/ptrace.h
index 6da197803efc..b4b951d570bb 100644
--- a/include/asm-sparc64/ptrace.h
+++ b/include/asm-sparc64/ptrace.h
@@ -8,6 +8,8 @@
  * stack during a system call and basically all traps.
  */
 
+#define PT_REGS_MAGIC 0x57ac6c00
+
 #ifndef __ASSEMBLY__
 
 struct pt_regs {
@@ -16,7 +18,19 @@ struct pt_regs {
         unsigned long tpc;
         unsigned long tnpc;
         unsigned int y;
-        unsigned int fprs;
+
+        /* We encode a magic number, PT_REGS_MAGIC, along
+         * with the %tt (trap type) register value at trap
+         * entry time.  The magic number allows us to identify
+         * accurately a trap stack frame in the stack
+         * unwinder, and the %tt value allows us to test
+         * things like "in a system call" etc. for an arbitray
+         * process.
+         *
+         * The PT_REGS_MAGIC is choosen such that it can be
+         * loaded completely using just a sethi instruction.
+         */
+        unsigned int magic;
 };
 
 struct pt_regs32 {
@@ -147,7 +161,7 @@ extern void __show_regs(struct pt_regs *);
 #define PT_V9_TPC    0x88
 #define PT_V9_TNPC   0x90
 #define PT_V9_Y      0x98
-#define PT_V9_FPRS   0x9c
+#define PT_V9_MAGIC  0x9c
 #define PT_TSTATE       PT_V9_TSTATE
 #define PT_TPC          PT_V9_TPC
 #define PT_TNPC         PT_V9_TNPC