Use movw instead of movl (or plain mov) when moving segment registers

into memory.  This is a nop on clang's assembler, but some assemblers
complain if the size suffix is incorrect.

Submitted by:	bde

diff --git a/sys/i386/i386/exception.s b/sys/i386/i386/exception.s
index 70c6d9d007585d206a987a7584abb7ea6fea9cdb..f91f51612269dc0c9ea7d75687264a4f8a1d3123 100644 (file)
--- a/sys/i386/i386/exception.s
+++ b/sys/i386/i386/exception.s
@@ -158,11 +158,11 @@ IDTVEC(xmm)
 alltraps:
        pushal
        pushl   $0
-       movl    %ds,(%esp)
+       movw    %ds,(%esp)
        pushl   $0
-       movl    %es,(%esp)
+       movw    %es,(%esp)
        pushl   $0
-       movl    %fs,(%esp)
+       movw    %fs,(%esp)
 alltraps_with_regs_pushed:
        SET_KERNEL_SREGS
        cld
@@ -237,11 +237,11 @@ IDTVEC(lcall_syscall)
        subl    $4,%esp                 /* skip over tf_trapno */
        pushal
        pushl   $0
-       movl    %ds,(%esp)
+       movw    %ds,(%esp)
        pushl   $0
-       movl    %es,(%esp)
+       movw    %es,(%esp)
        pushl   $0
-       movl    %fs,(%esp)
+       movw    %fs,(%esp)
        SET_KERNEL_SREGS
        cld
        FAKE_MCOUNT(TF_EIP(%esp))
@@ -266,11 +266,11 @@ IDTVEC(int0x80_syscall)
        subl    $4,%esp                 /* skip over tf_trapno */
        pushal
        pushl   $0
-       movl    %ds,(%esp)
+       movw    %ds,(%esp)
        pushl   $0
-       movl    %es,(%esp)
+       movw    %es,(%esp)
        pushl   $0
-       movl    %fs,(%esp)
+       movw    %fs,(%esp)
        SET_KERNEL_SREGS
        cld
        FAKE_MCOUNT(TF_EIP(%esp))
@@ -426,15 +426,15 @@ doreti_iret_fault:
        subl    $8,%esp
        pushal
        pushl   $0
-       movl    %ds,(%esp)
+       movw    %ds,(%esp)
        .globl  doreti_popl_ds_fault
 doreti_popl_ds_fault:
        pushl   $0
-       movl    %es,(%esp)
+       movw    %es,(%esp)
        .globl  doreti_popl_es_fault
 doreti_popl_es_fault:
        pushl   $0
-       movl    %fs,(%esp)
+       movw    %fs,(%esp)
        .globl  doreti_popl_fs_fault
 doreti_popl_fs_fault:
        sti

diff --git a/sys/i386/include/asmacros.h b/sys/i386/include/asmacros.h
index 91c25f725dfa0d800f755a6edf719edc664f95a0..d14f0794dc0f0ae7121ed3430c766e7aa8dcffd4 100644 (file)
--- a/sys/i386/include/asmacros.h
+++ b/sys/i386/include/asmacros.h
@@ -147,11 +147,11 @@
        pushl   $0 ;            /* dummy trap type */                   \
        pushal ;                /* 8 ints */                            \
        pushl   $0 ;            /* save data and extra segments ... */  \
-       mov     %ds,(%esp) ;                                            \
+       movw    %ds,(%esp) ;                                            \
        pushl   $0 ;                                                    \
-       mov     %es,(%esp) ;                                            \
+       movw    %es,(%esp) ;                                            \
        pushl   $0 ;                                                    \
-       mov     %fs,(%esp)
+       movw    %fs,(%esp)
        
 #define        POP_FRAME                                                       \
        popl    %fs ;                                                   \