ARC: pt_regs update #3: Remove unused gutter at start of callee_regs
This is trickier than prev two:
* context switching code saves kernel mode callee regs in the format of
struct callee_regs thus needs adjustment. This also reduces the height
of topmost kernel stack frame by 1 word.
* Since kernel stack unwinder is sensitive to height of topmost kernel
stack frame, that needs a word of adjustment too.
ptrace needs a bit of updating since pt_regs now diverges from
user_regs_struct.
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
diff --git a/arch/arc/kernel/ptrace.c b/arch/arc/kernel/ptrace.c
index 6e467e3..3332385 100644
--- a/arch/arc/kernel/ptrace.c
+++ b/arch/arc/kernel/ptrace.c
@@ -48,6 +48,7 @@
REG_O_ZERO(pad);
REG_O_CHUNK(scratch, callee, ptregs);
+ REG_O_ZERO(pad2);
REG_O_CHUNK(callee, efa, cregs);
REG_O_CHUNK(efa, stop_pc, &target->thread.fault_address);
@@ -96,8 +97,9 @@
offsetof(struct user_regs_struct, LOC) + 4);
REG_IGNORE_ONE(pad);
- /* TBD: disallow updates to STATUS32, orig_r8 etc*/
- REG_IN_CHUNK(scratch, callee, ptregs); /* pt_regs[bta..orig_r8] */
+ /* TBD: disallow updates to STATUS32 etc*/
+ REG_IN_CHUNK(scratch, pad2, ptregs); /* pt_regs[bta..sp] */
+ REG_IGNORE_ONE(pad2);
REG_IN_CHUNK(callee, efa, cregs); /* callee_regs[r25..r13] */
REG_IGNORE_ONE(efa); /* efa update invalid */
REG_IN_ONE(stop_pc, &ptregs->ret); /* stop_pc: PC update */