2 files changed, 9 insertions, 10 deletions

diff --git a/arch/x86/include/asm/calling.h b/arch/x86/include/asm/calling.h
index cb4c73bfeb48..76659b67fd11 100644
--- a/arch/x86/include/asm/calling.h
+++ b/arch/x86/include/asm/calling.h
@@ -85,7 +85,7 @@ For 32-bit we have the following conventions - kernel is built with
 #define ARGOFFSET       R11
 #define SWFRAME         ORIG_RAX
 
-        .macro SAVE_ARGS addskip=0, save_rcx=1, save_r891011=1
+        .macro SAVE_ARGS addskip=0, save_rcx=1, save_r891011=1, rax_enosys=0
         subq  $9*8+\addskip, %rsp
         CFI_ADJUST_CFA_OFFSET   9*8+\addskip
         movq_cfi rdi, 8*8
@@ -96,7 +96,11 @@ For 32-bit we have the following conventions - kernel is built with
         movq_cfi rcx, 5*8
         .endif
 
+        .if \rax_enosys
+        movq $-ENOSYS, 4*8(%rsp)
+        .else
         movq_cfi rax, 4*8
+        .endif
 
         .if \save_r891011
         movq_cfi r8,  3*8
diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S
index 2fac1343a90b..0bd6d3c28064 100644
--- a/arch/x86/kernel/entry_64.S
+++ b/arch/x86/kernel/entry_64.S
@@ -404,8 +404,8 @@ GLOBAL(system_call_after_swapgs)
          * and short:
          */
         ENABLE_INTERRUPTS(CLBR_NONE)
-        SAVE_ARGS 8,0
-        movq  %rax,ORIG_RAX-ARGOFFSET(%rsp)
+        SAVE_ARGS 8, 0, rax_enosys=1
+        movq_cfi rax,(ORIG_RAX-ARGOFFSET)
         movq  %rcx,RIP-ARGOFFSET(%rsp)
         CFI_REL_OFFSET rip,RIP-ARGOFFSET
         testl $_TIF_WORK_SYSCALL_ENTRY,TI_flags+THREAD_INFO(%rsp,RIP-ARGOFFSET)
@@ -417,7 +417,7 @@ system_call_fastpath:
         andl $__SYSCALL_MASK,%eax
         cmpl $__NR_syscall_max,%eax
 #endif
-        ja badsys
+        ja ret_from_sys_call  /* and return regs->ax */
         movq %r10,%rcx
         call *sys_call_table(,%rax,8)  # XXX:    rip relative
         movq %rax,RAX-ARGOFFSET(%rsp)
@@ -476,10 +476,6 @@ sysret_signal:
         FIXUP_TOP_OF_STACK %r11, -ARGOFFSET
         jmp int_check_syscall_exit_work
 
-badsys:
-        movq $-ENOSYS,RAX-ARGOFFSET(%rsp)
-        jmp ret_from_sys_call
-
 #ifdef CONFIG_AUDITSYSCALL
         /*
          * Fast path for syscall audit without full syscall trace.
@@ -519,7 +515,6 @@ tracesys:
         jz auditsys
 #endif
         SAVE_REST
-        movq $-ENOSYS,RAX(%rsp) /* ptrace can change this for a bad syscall */
         FIXUP_TOP_OF_STACK %rdi
         movq %rsp,%rdi
         call syscall_trace_enter
@@ -536,7 +531,7 @@ tracesys:
         andl $__SYSCALL_MASK,%eax
         cmpl $__NR_syscall_max,%eax
 #endif
-        ja   int_ret_from_sys_call      /* RAX(%rsp) set to -ENOSYS above */
+        ja   int_ret_from_sys_call      /* RAX(%rsp) is already set */
         movq %r10,%rcx  /* fixup for C */
         call *sys_call_table(,%rax,8)
         movq %rax,RAX-ARGOFFSET(%rsp)