powerpc/watchpoint: Add hw_len wherever missing

There are couple of places where we set len but not hw_len. For
ptrace/perf watchpoints, when CONFIG_HAVE_HW_BREAKPOINT=Y, hw_len
will be calculated and set internally while parsing watchpoint.
But when CONFIG_HAVE_HW_BREAKPOINT=N, we need to manually set
'hw_len'. Similarly for xmon as well, hw_len needs to be set
directly.

Fixes: b57aeab8 ("powerpc/watchpoint: Fix length calculation for unaligned target")
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200902042945.129369-7-ravi.bangoria@linux.ibm.com

arch/powerpc/kernel/ptrace/ptrace-noadv.c

@@ -219,6 +219,7 @@ long ppc_set_hwdebug(struct task_struct *child, struct ppc_hw_breakpoint *bp_inf
 	brk.address = ALIGN_DOWN(bp_info->addr, HW_BREAKPOINT_SIZE);
 	brk.type = HW_BRK_TYPE_TRANSLATE | HW_BRK_TYPE_PRIV_ALL;
 	brk.len = DABR_MAX_LEN;
+	brk.hw_len = DABR_MAX_LEN;
 	if (bp_info->trigger_type & PPC_BREAKPOINT_TRIGGER_READ)
 		brk.type |= HW_BRK_TYPE_READ;
 	if (bp_info->trigger_type & PPC_BREAKPOINT_TRIGGER_WRITE)

arch/powerpc/xmon/xmon.c

@@ -969,6 +969,7 @@ static void insert_cpu_bpts(void)
 			brk.address = dabr[i].address;
 			brk.type = (dabr[i].enabled & HW_BRK_TYPE_DABR) | HW_BRK_TYPE_PRIV_ALL;
 			brk.len = 8;
+			brk.hw_len = 8;
 			__set_breakpoint(i, &brk);
 		}
 	}