1 files changed, 20 insertions, 5 deletions

diff --git a/arch/s390/kernel/entry64.S b/arch/s390/kernel/entry64.S
index 7a2d22dda9ef..14eec6a9577e 100644
--- a/arch/s390/kernel/entry64.S
+++ b/arch/s390/kernel/entry64.S
@@ -80,14 +80,21 @@ _TIF_EXIT_SIE = (_TIF_SIGPENDING | _TIF_NEED_RESCHED | _TIF_MCCK_PENDING)
 #endif
         .endm
 
-        .macro  HANDLE_SIE_INTERCEPT scratch
+        .macro  HANDLE_SIE_INTERCEPT scratch,pgmcheck
 #if defined(CONFIG_KVM) || defined(CONFIG_KVM_MODULE)
         tmhh    %r8,0x0001              # interrupting from user ?
         jnz     .+42
         lgr     \scratch,%r9
         slg     \scratch,BASED(.Lsie_loop)
         clg     \scratch,BASED(.Lsie_length)
+        .if     \pgmcheck
+        # Some program interrupts are suppressing (e.g. protection).
+        # We must also check the instruction after SIE in that case.
+        # do_protection_exception will rewind to rewind_pad
+        jh      .+22
+        .else
         jhe     .+22
+        .endif
         lg      %r9,BASED(.Lsie_loop)
         SPP     BASED(.Lhost_id)        # set host id
 #endif
@@ -390,7 +397,7 @@ ENTRY(pgm_check_handler)
         lg      %r12,__LC_THREAD_INFO
         larl    %r13,system_call
         lmg     %r8,%r9,__LC_PGM_OLD_PSW
-        HANDLE_SIE_INTERCEPT %r14
+        HANDLE_SIE_INTERCEPT %r14,1
         tmhh    %r8,0x0001              # test problem state bit
         jnz     1f                      # -> fault in user space
         tmhh    %r8,0x4000              # PER bit set in old PSW ?
@@ -466,7 +473,7 @@ ENTRY(io_int_handler)
         lg      %r12,__LC_THREAD_INFO
         larl    %r13,system_call
         lmg     %r8,%r9,__LC_IO_OLD_PSW
-        HANDLE_SIE_INTERCEPT %r14
+        HANDLE_SIE_INTERCEPT %r14,0
         SWITCH_ASYNC __LC_SAVE_AREA_ASYNC,__LC_ASYNC_STACK,STACK_SHIFT
         tmhh    %r8,0x0001              # interrupting from user?
         jz      io_skip
@@ -612,7 +619,7 @@ ENTRY(ext_int_handler)
         lg      %r12,__LC_THREAD_INFO
         larl    %r13,system_call
         lmg     %r8,%r9,__LC_EXT_OLD_PSW
-        HANDLE_SIE_INTERCEPT %r14
+        HANDLE_SIE_INTERCEPT %r14,0
         SWITCH_ASYNC __LC_SAVE_AREA_ASYNC,__LC_ASYNC_STACK,STACK_SHIFT
         tmhh    %r8,0x0001              # interrupting from user ?
         jz      ext_skip
@@ -660,7 +667,7 @@ ENTRY(mcck_int_handler)
         lg      %r12,__LC_THREAD_INFO
         larl    %r13,system_call
         lmg     %r8,%r9,__LC_MCK_OLD_PSW
-        HANDLE_SIE_INTERCEPT %r14
+        HANDLE_SIE_INTERCEPT %r14,0
         tm      __LC_MCCK_CODE,0x80     # system damage?
         jo      mcck_panic              # yes -> rest of mcck code invalid
         lghi    %r14,__LC_CPU_TIMER_SAVE_AREA
@@ -959,6 +966,13 @@ ENTRY(sie64a)
         stg     %r3,__SF_EMPTY+8(%r15)          # save guest register save area
         xc      __SF_EMPTY+16(8,%r15),__SF_EMPTY+16(%r15) # host id == 0
         lmg     %r0,%r13,0(%r3)                 # load guest gprs 0-13
+# some program checks are suppressing. C code (e.g. do_protection_exception)
+# will rewind the PSW by the ILC, which is 4 bytes in case of SIE. Other
+# instructions in the sie_loop should not cause program interrupts. So
+# lets use a nop (47 00 00 00) as a landing pad.
+# See also HANDLE_SIE_INTERCEPT
+rewind_pad:
+        nop     0
 sie_loop:
         lg      %r14,__LC_THREAD_INFO           # pointer thread_info struct
         tm      __TI_flags+7(%r14),_TIF_EXIT_SIE
@@ -998,6 +1012,7 @@ sie_fault:
 .Lhost_id:
         .quad   0
 
+        EX_TABLE(rewind_pad,sie_fault)
         EX_TABLE(sie_loop,sie_fault)
 #endif