From e4d82692f4513ccf78de548b8ecea58adf03fa9a Mon Sep 17 00:00:00 2001 From: Martin Schwidefsky Date: Mon, 31 Jan 2011 11:30:05 +0100 Subject: [PATCH] [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 Signed-off-by: Martin Schwidefsky --- arch/s390/lib/uaccess_std.c | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) diff --git a/arch/s390/lib/uaccess_std.c b/arch/s390/lib/uaccess_std.c index 07deaeee14c8..a6c4f7ed24a4 100644 --- a/arch/s390/lib/uaccess_std.c +++ b/arch/s390/lib/uaccess_std.c @@ -125,9 +125,9 @@ static size_t copy_in_user_std(size_t size, void __user *to, 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 @@ static size_t copy_in_user_std(size_t size, void __user *to, "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 @@ static size_t clear_user_std(size_t size, void __user *to) 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 @@ static size_t clear_user_std(size_t size, void __user *to) "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"); -- 2.39.5