um: Mark 32bit syscall helpers as clobbering memory

The 64bit helper are marked to clobber the memory, but the 32bit ones
are not. Add the appropriate clobber to the 32bit helper routines so
that the compiler cannot do invalid optimizations.

Signed-off-by: Benjamin Berg <benjamin@sipsolutions.net>
Signed-off-by: Richard Weinberger <richard@nod.at>

diff --git a/arch/x86/um/shared/sysdep/stub_32.h b/arch/x86/um/shared/sysdep/stub_32.h
index 4e763f8b380f5ac762fc1e5c1482f43820391376..ea8b5a2d67afb95cb2deb76efa4059f7b602771d 100644 (file)
--- a/arch/x86/um/shared/sysdep/stub_32.h
+++ b/arch/x86/um/shared/sysdep/stub_32.h
@@ -16,7 +16,8 @@ static __always_inline long stub_syscall0(long syscall)
 {
        long ret;
 
-       __asm__ volatile ("int $0x80" : "=a" (ret) : "0" (syscall));
+       __asm__ volatile ("int $0x80" : "=a" (ret) : "0" (syscall)
+                       : "memory");
 
        return ret;
 }
@@ -25,7 +26,8 @@ static __always_inline long stub_syscall1(long syscall, long arg1)
 {
        long ret;
 
-       __asm__ volatile ("int $0x80" : "=a" (ret) : "0" (syscall), "b" (arg1));
+       __asm__ volatile ("int $0x80" : "=a" (ret) : "0" (syscall), "b" (arg1)
+                       : "memory");
 
        return ret;
 }
@@ -35,7 +37,8 @@ static __always_inline long stub_syscall2(long syscall, long arg1, long arg2)
        long ret;
 
        __asm__ volatile ("int $0x80" : "=a" (ret) : "0" (syscall), "b" (arg1),
-                       "c" (arg2));
+                       "c" (arg2)
+                       : "memory");
 
        return ret;
 }
@@ -46,7 +49,8 @@ static __always_inline long stub_syscall3(long syscall, long arg1, long arg2,
        long ret;
 
        __asm__ volatile ("int $0x80" : "=a" (ret) : "0" (syscall), "b" (arg1),
-                       "c" (arg2), "d" (arg3));
+                       "c" (arg2), "d" (arg3)
+                       : "memory");
 
        return ret;
 }
@@ -57,7 +61,8 @@ static __always_inline long stub_syscall4(long syscall, long arg1, long arg2,
        long ret;
 
        __asm__ volatile ("int $0x80" : "=a" (ret) : "0" (syscall), "b" (arg1),
-                       "c" (arg2), "d" (arg3), "S" (arg4));
+                       "c" (arg2), "d" (arg3), "S" (arg4)
+                       : "memory");
 
        return ret;
 }
@@ -68,7 +73,8 @@ static __always_inline long stub_syscall5(long syscall, long arg1, long arg2,
        long ret;
 
        __asm__ volatile ("int $0x80" : "=a" (ret) : "0" (syscall), "b" (arg1),
-                       "c" (arg2), "d" (arg3), "S" (arg4), "D" (arg5));
+                       "c" (arg2), "d" (arg3), "S" (arg4), "D" (arg5)
+                       : "memory");
 
        return ret;
 }