[PATCH 18/23] Make register values available to Score panicnotifiers

From: David VomLehn
Date: Mon Apr 12 2010 - 02:04:43 EST


The save_ptregs() function has not been tested or even built. I will need
help to complete this.

Signed-off-by: David VomLehn <dvomlehn@xxxxxxxxx>
---
arch/score/include/asm/ptrace.h | 136 +++++++++++++++++++++++++++++++++++++++
arch/score/kernel/traps.c | 2 +-
2 files changed, 137 insertions(+), 1 deletions(-)

diff --git a/arch/score/include/asm/ptrace.h b/arch/score/include/asm/ptrace.h
index e89dc9b..d9a1293 100644
--- a/arch/score/include/asm/ptrace.h
+++ b/arch/score/include/asm/ptrace.h
@@ -91,6 +91,142 @@ extern int read_tsk_short(struct task_struct *, unsigned long,

#define arch_has_single_step() (1)

+
+/* Macros for saving the contents of registers and for the output constraint
+ * for those registers */
+#include "/home/vomlehn/git/kernel.org/ptreg.h"
+#define PTREG_SAVE(r, name) "sw " #r ", %[" #name "]\n"
+#define PTREG_SAVE_R(i) PTREG_SAVE_I(r, r, i)
+
+#define PTREG_SAVE_R(regs, i) PTREG_SAVE_I(regs, r, r, i)
+
+#define arch_has_save_ptregs 1
+
+/**
+ * save_ptregs - save processor registers for backtracing
+ * @regs: Pointer to &struct pt_regs structure in which to save the
+ * registers
+ *
+ * Returns a constant pointer to @regs.
+ *
+ * This function must be called first in a function. There must be no
+ * auto variables defined that are initialized before calling this function.
+ */
+static __always_inline
+const struct pt_regs *save_ptregs(struct pt_regs *regs)
+{
+ __asm__ __volatile__ (
+ PTREG_SAVE_R(0)
+ PTREG_SAVE_R(1)
+ PTREG_SAVE_R(2)
+ PTREG_SAVE_R(3)
+ PTREG_SAVE_R(4)
+ PTREG_SAVE_R(5)
+ PTREG_SAVE_R(6)
+ PTREG_SAVE_R(7)
+ PTREG_SAVE_R(8)
+ PTREG_SAVE_R(9)
+ PTREG_SAVE_R(10)
+ PTREG_SAVE_R(11)
+ PTREG_SAVE_R(12)
+ PTREG_SAVE_R(13)
+ PTREG_SAVE_R(14)
+ PTREG_SAVE_R(15)
+ PTREG_SAVE_R(16)
+ PTREG_SAVE_R(17)
+ PTREG_SAVE_R(18)
+ PTREG_SAVE_R(19)
+ PTREG_SAVE_R(20)
+ PTREG_SAVE_R(21)
+ PTREG_SAVE_R(22)
+ PTREG_SAVE_R(23)
+ PTREG_SAVE_R(24)
+ PTREG_SAVE_R(25)
+ PTREG_SAVE_R(26)
+ PTREG_SAVE_R(27)
+ PTREG_SAVE_R(28)
+ PTREG_SAVE_R(29)
+ PTREG_SAVE_R(30)
+ PTREG_SAVE_R(31)
+
+ PTREG_SAVE(sr0, sr0)
+ PTREG_SAVE(sr1, sr1)
+ PTREG_SAVE(sr2, sr2)
+
+ "mfcehl r30, r31\n"
+ PTREG_SAVE(r30, cp0_ceh)
+ PTREG_SAVE(r31, cp0_cel)
+
+ "mfcr r31, cr0\n"
+ PTREG_SAVE(r31, cp0_ecr)
+
+ "mfcr r31, cr1\n"
+ PTREG_SAVE(r31, cp0_condition)
+
+ "mfcr r31, cr2\n"
+ PTREG_SAVE(r31, cp0_ecr)
+
+ "mfcr r31, cr6\n"
+ PTREG_SAVE(r31, cp0_ema)
+
+ /*
+ * The current location is the one for which the register
+ * values are correct, even if some had been modified on
+ * function entry. So, the current location is the value to
+ * save as the execution address.
+ */
+ "1:\n"
+ "la r1, 1b"
+ PTREG_SAVE(r1, cp0_epc)
+ :
+ PTREG_OUT_R(regs, 0)
+ PTREG_OUT_R(regs, 1)
+ PTREG_OUT_R(regs, 2)
+ PTREG_OUT_R(regs, 3)
+ PTREG_OUT_R(regs, 4)
+ PTREG_OUT_R(regs, 5)
+ PTREG_OUT_R(regs, 6)
+ PTREG_OUT_R(regs, 7)
+ PTREG_OUT_R(regs, 8)
+ PTREG_OUT_R(regs, 9)
+ PTREG_OUT_R(regs, 10)
+ PTREG_OUT_R(regs, 11)
+ PTREG_OUT_R(regs, 12)
+ PTREG_OUT_R(regs, 13)
+ PTREG_OUT_R(regs, 14)
+ PTREG_OUT_R(regs, 15)
+ PTREG_OUT_R(regs, 16)
+ PTREG_OUT_R(regs, 17)
+ PTREG_OUT_R(regs, 18)
+ PTREG_OUT_R(regs, 19)
+ PTREG_OUT_R(regs, 20)
+ PTREG_OUT_R(regs, 21)
+ PTREG_OUT_R(regs, 22)
+ PTREG_OUT_R(regs, 23)
+ PTREG_OUT_R(regs, 24)
+ PTREG_OUT_R(regs, 25)
+ PTREG_OUT_R(regs, 26)
+ PTREG_OUT_R(regs, 27)
+ PTREG_OUT_R(regs, 28)
+ PTREG_OUT_R(regs, 29)
+ PTREG_OUT_R(regs, 30)
+ PTREG_OUT_R(regs, 31)
+ PTREG_OUT(regs, cel, cel)
+ PTREG_OUT(regs, ceh, ceh)
+ PTREG_OUT(regs, sr0, sr0)
+ PTREG_OUT(regs, sr1, sr1)
+ PTREG_OUT(regs, sr2, sr2)
+ PTREG_OUT(regs, cp0_epc, cp0_epc)
+ PTREG_OUT(regs, cp0_ema, cp0_ema)
+ PTREG_OUT(regs, cp0_psr, cp0_psr)
+ PTREG_OUT(regs, cp0_ecr, cp0_ecr)
+ PTREG_OUT(regs, cp0_condition, cp0_condition)
+ :
+ "r30", "r31"
+ );
+
+ return regs;
+}
#endif /* __KERNEL__ */

#endif /* _ASM_SCORE_PTRACE_H */
diff --git a/arch/score/kernel/traps.c b/arch/score/kernel/traps.c
index 0e46fb1..1331829 100644
--- a/arch/score/kernel/traps.c
+++ b/arch/score/kernel/traps.c
@@ -283,7 +283,7 @@ asmlinkage void do_reserved(struct pt_regs *regs)
*/
die_if_kernel("do_reserved execution Exception", regs);
show_regs(regs);
- panic("Caught reserved exception - should not happen.");
+ panic_with_regs(regs, "Caught reserved exception - should not happen.");
}

/*
--
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