[S390] missing sacf in uaccess
The uaccess functions copy_in_user_std and clear_user_std fail to
switch back from secondary space mode to primary space mode with sacf
in case of an unresolvable page fault. We need to make sure that the
switch back to primary mode is done in all cases, otherwise the code
following the uaccess inline assembly will crash.
Reported-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/lib/uaccess_std.c b/arch/s390/lib/uaccess_std.c
index 07deaee..a6c4f7e 100644
--- a/arch/s390/lib/uaccess_std.c
+++ b/arch/s390/lib/uaccess_std.c
@@ -125,9 +125,9 @@
unsigned long tmp1;
asm volatile(
+ " sacf 256\n"
" "AHI" %0,-1\n"
" jo 5f\n"
- " sacf 256\n"
" bras %3,3f\n"
"0:"AHI" %0,257\n"
"1: mvc 0(1,%1),0(%2)\n"
@@ -142,9 +142,8 @@
"3:"AHI" %0,-256\n"
" jnm 2b\n"
"4: ex %0,1b-0b(%3)\n"
- " sacf 0\n"
"5: "SLR" %0,%0\n"
- "6:\n"
+ "6: sacf 0\n"
EX_TABLE(1b,6b) EX_TABLE(2b,0b) EX_TABLE(4b,0b)
: "+a" (size), "+a" (to), "+a" (from), "=a" (tmp1)
: : "cc", "memory");
@@ -156,9 +155,9 @@
unsigned long tmp1, tmp2;
asm volatile(
+ " sacf 256\n"
" "AHI" %0,-1\n"
" jo 5f\n"
- " sacf 256\n"
" bras %3,3f\n"
" xc 0(1,%1),0(%1)\n"
"0:"AHI" %0,257\n"
@@ -178,9 +177,8 @@
"3:"AHI" %0,-256\n"
" jnm 2b\n"
"4: ex %0,0(%3)\n"
- " sacf 0\n"
"5: "SLR" %0,%0\n"
- "6:\n"
+ "6: sacf 0\n"
EX_TABLE(1b,6b) EX_TABLE(2b,0b) EX_TABLE(4b,0b)
: "+a" (size), "+a" (to), "=a" (tmp1), "=a" (tmp2)
: : "cc", "memory");