1 files changed, 12 insertions, 0 deletions

diff --git a/arch/s390/kernel/entry64.S b/arch/s390/kernel/entry64.S
index 56f5f613b868..8b956d1538f5 100644
--- a/arch/s390/kernel/entry64.S
+++ b/arch/s390/kernel/entry64.S
@@ -518,6 +518,8 @@ pgm_no_vtime2:
 #endif
         lg      %r9,__LC_THREAD_INFO    # load pointer to thread_info struct
         lg      %r1,__TI_task(%r9)
+        tm      SP_PSW+1(%r15),0x01     # kernel per event ?
+        jz      kernel_per
         mvc     __THREAD_per+__PER_atmid(2,%r1),__LC_PER_ATMID
         mvc     __THREAD_per+__PER_address(8,%r1),__LC_PER_ADDRESS
         mvc     __THREAD_per+__PER_access_id(1,%r1),__LC_PER_ACCESS_ID
@@ -553,6 +555,16 @@ pgm_no_vtime3:
         stosm   __SF_EMPTY(%r15),0x03   # reenable interrupts
         j       sysc_do_svc
 
+#
+# per was called from kernel, must be kprobes
+#
+kernel_per:
+        lhi     %r0,__LC_PGM_OLD_PSW
+        sth     %r0,SP_TRAP(%r15)       # set trap indication to pgm check
+        la      %r2,SP_PTREGS(%r15)     # address of register-save area
+        larl    %r14,sysc_leave         # load adr. of system ret, no work
+        jg      do_single_step          # branch to do_single_step
+
 /*
  * IO interrupt handler routine
  */