[S390] add kprobes support.
Signed-off-by: Michael Grundy <grundym@us.ibm.com>
Signed-off-by: David Wilder <dwilder@us.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/kernel/entry.S b/arch/s390/kernel/entry.S
index 5b5799a..0c712b7 100644
--- a/arch/s390/kernel/entry.S
+++ b/arch/s390/kernel/entry.S
@@ -505,6 +505,8 @@
mvc __THREAD_per+__PER_address(4,%r1),__LC_PER_ADDRESS
mvc __THREAD_per+__PER_access_id(1,%r1),__LC_PER_ACCESS_ID
oi __TI_flags+3(%r9),_TIF_SINGLE_STEP # set TIF_SINGLE_STEP
+ tm SP_PSW+1(%r15),0x01 # kernel per event ?
+ bz BASED(kernel_per)
l %r3,__LC_PGM_ILC # load program interruption code
la %r8,0x7f
nr %r8,%r3 # clear per-event-bit and ilc
@@ -536,6 +538,16 @@
stosm __SF_EMPTY(%r15),0x03 # reenable interrupts
b BASED(sysc_do_svc)
+#
+# per was called from kernel, must be kprobes
+#
+kernel_per:
+ mvi SP_TRAP+1(%r15),0x28 # set trap indication to pgm check
+ la %r2,SP_PTREGS(%r15) # address of register-save area
+ l %r1,BASED(.Lhandle_per) # load adr. of per handler
+ la %r14,BASED(sysc_leave) # load adr. of system return
+ br %r1 # branch to do_single_step
+
/*
* IO interrupt handler routine
*/