Module Name: src
Committed By: maxv
Date: Wed Nov 1 09:17:28 UTC 2017
Modified Files:
src/sys/arch/amd64/amd64: copy.S cpufunc.S
Log Message:
Don't fall through functions, explicitly jump instead. While here don't
call smap_enable twice (harmless), and add END() markers.
To generate a diff of this commit:
cvs rdiff -u -r1.27 -r1.28 src/sys/arch/amd64/amd64/copy.S
cvs rdiff -u -r1.30 -r1.31 src/sys/arch/amd64/amd64/cpufunc.S
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/arch/amd64/amd64/copy.S
diff -u src/sys/arch/amd64/amd64/copy.S:1.27 src/sys/arch/amd64/amd64/copy.S:1.28
--- src/sys/arch/amd64/amd64/copy.S:1.27 Mon Oct 30 17:06:42 2017
+++ src/sys/arch/amd64/amd64/copy.S Wed Nov 1 09:17:28 2017
@@ -1,4 +1,4 @@
-/* $NetBSD: copy.S,v 1.27 2017/10/30 17:06:42 maxv Exp $ */
+/* $NetBSD: copy.S,v 1.28 2017/11/01 09:17:28 maxv Exp $ */
/*
* Copyright (c) 2001 Wasabi Systems, Inc.
@@ -258,19 +258,17 @@ END(copyin)
NENTRY(copy_efault)
movq $EFAULT,%rax
-
-/*
- * kcopy_fault is used by kcopy and copy_fault is used by copyin/out.
- *
- * they're distinguished for lazy pmap switching. see trap().
- */
+ ret
+END(copy_efault)
NENTRY(kcopy_fault)
ret
+END(kcopy_fault)
NENTRY(copy_fault)
callq smap_enable
ret
+END(copy_fault)
ENTRY(copyoutstr)
DEFERRED_SWITCH_CHECK
@@ -362,6 +360,8 @@ END(copyinstr)
ENTRY(copystr_efault)
movl $EFAULT,%eax
+ jmp copystr_return
+END(copystr_efault)
ENTRY(copystr_fault)
callq smap_enable
@@ -371,8 +371,8 @@ copystr_return:
jz 8f
subq %rdx,%r8
movq %r8,(%r9)
-
8: ret
+END(copystr_fault)
ENTRY(copystr)
xchgq %rdi,%rsi
@@ -564,10 +564,13 @@ END(ucas_32)
ENTRY(ucas_efault)
movq $EFAULT,%rax
+ ret
+END(ucas_efault)
NENTRY(ucas_fault)
callq smap_enable
ret
+END(ucas_fault)
/*
* int ucas_ptr(volatile void **uptr, void *old, void *new, void **ret);
Index: src/sys/arch/amd64/amd64/cpufunc.S
diff -u src/sys/arch/amd64/amd64/cpufunc.S:1.30 src/sys/arch/amd64/amd64/cpufunc.S:1.31
--- src/sys/arch/amd64/amd64/cpufunc.S:1.30 Mon Oct 30 17:06:42 2017
+++ src/sys/arch/amd64/amd64/cpufunc.S Wed Nov 1 09:17:28 2017
@@ -1,4 +1,4 @@
-/* $NetBSD: cpufunc.S,v 1.30 2017/10/30 17:06:42 maxv Exp $ */
+/* $NetBSD: cpufunc.S,v 1.31 2017/11/01 09:17:28 maxv Exp $ */
/*
* Copyright (c) 1998, 2007, 2008 The NetBSD Foundation, Inc.
@@ -424,8 +424,7 @@ END(__byte_swap_u16_variable)
* Load a new GDT pointer (and do any necessary cleanup).
* XXX It's somewhat questionable whether reloading all the segment registers
* is necessary, since the actual descriptor data is not changed except by
- * process creation and exit, both of which clean up via task switches. OTOH,
- * this only happens at run time when the GDT is resized.
+ * process creation and exit, both of which clean up via task switches.
*/
#ifndef XEN
ENTRY(lgdt)
@@ -435,19 +434,21 @@ ENTRY(lgdt)
/* Flush the prefetch q. */
jmp 1f
nop
-1: /* Reload "stale" selectors. */
-#else /* XEN */
+1: jmp _C_LABEL(lgdt_finish)
+END(lgdt)
+#endif
+
/*
* void lgdt_finish(void);
* Reload segments after a GDT change
*/
ENTRY(lgdt_finish)
-#endif /* XEN */
movl $GSEL(GDATA_SEL, SEL_KPL),%eax
movl %eax,%ds
movl %eax,%es
movl %eax,%ss
- /* FALLTHROUGH */
+ jmp _C_LABEL(x86_flush)
+END(lgdt_finish)
/*
* void x86_flush()
