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Diffstat (limited to 'arch/arc/include/uapi/asm/ptrace.h')
-rw-r--r--arch/arc/include/uapi/asm/ptrace.h15
1 files changed, 9 insertions, 6 deletions
diff --git a/arch/arc/include/uapi/asm/ptrace.h b/arch/arc/include/uapi/asm/ptrace.h
index 30333cec0fe..2618cc13ba7 100644
--- a/arch/arc/include/uapi/asm/ptrace.h
+++ b/arch/arc/include/uapi/asm/ptrace.h
@@ -20,28 +20,31 @@
*
* This is to decouple pt_regs from user-space ABI, to be able to change it
* w/o affecting the ABI.
- * Although the layout (initial padding) is similar to pt_regs to have some
- * optimizations when copying pt_regs to/from user_regs_struct.
+ *
+ * The intermediate pad,pad2 are relics of initial layout based on pt_regs
+ * for optimizations when copying pt_regs to/from user_regs_struct.
+ * We no longer need them, but can't be changed as they are part of ABI now.
*
* Also, sigcontext only care about the scratch regs as that is what we really
- * save/restore for signal handling.
+ * save/restore for signal handling. However gdb also uses the same struct
+ * hence callee regs need to be in there too.
*/
struct user_regs_struct {
+ long pad;
struct {
- long pad;
long bta, lp_start, lp_end, lp_count;
long status32, ret, blink, fp, gp;
long r12, r11, r10, r9, r8, r7, r6, r5, r4, r3, r2, r1, r0;
long sp;
} scratch;
+ long pad2;
struct {
- long pad;
long r25, r24, r23, r22, r21, r20;
long r19, r18, r17, r16, r15, r14, r13;
} callee;
long efa; /* break pt addr, for break points in delay slots */
- long stop_pc; /* give dbg stop_pc directly after checking orig_r8 */
+ long stop_pc; /* give dbg stop_pc after ensuring brkpt trap */
};
#endif /* !__ASSEMBLY__ */