[PATCH] x86/entry: Mark check_user_regs() noinstr

[Peter Zijlstra]

On Fri, Jun 26, 2020 at 10:21:11AM -0700, Andy Lutomirski wrote:

> +static void check_user_regs(struct pt_regs *regs)

---
Subject: x86/entry: Mark check_user_regs() noinstr

vmlinux.o: warning: objtool: do_syscall_64()+0xb: call to check_user_regs() leaves .noinstr.text section
vmlinux.o: warning: objtool: do_int80_syscall_32()+0x4: call to check_user_regs() leaves .noinstr.text section
vmlinux.o: warning: objtool: do_fast_syscall_32()+0x25: call to check_user_regs() leaves .noinstr.text section
vmlinux.o: warning: objtool: idtentry_enter_cond_rcu()+0x3d: call to check_user_regs() leaves .noinstr.text section
vmlinux.o: warning: objtool: idtentry_enter_user()+0x0: call to check_user_regs() leaves .noinstr.text section

Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
---
 arch/x86/entry/common.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/entry/common.c b/arch/x86/entry/common.c
index e83b3f14897c..ea7b515e3bc2 100644
--- a/arch/x86/entry/common.c
+++ b/arch/x86/entry/common.c
@@ -46,7 +46,7 @@
 #include <trace/events/syscalls.h>
 
 /* Check that the stack and regs on entry from user mode are sane. */
-static void check_user_regs(struct pt_regs *regs)
+static noinstr void check_user_regs(struct pt_regs *regs)
 {
 	if (IS_ENABLED(CONFIG_DEBUG_ENTRY)) {
 		/*