i386 and amd64 have only one syscall entry point now, so simply the

EIP/RIP adjustment for ERESTART

ok mlarkin@

diff --git a/sys/arch/amd64/amd64/locore.S b/sys/arch/amd64/amd64/locore.S
index c4d9cee..d3f9cff 100644 (file)
--- a/sys/arch/amd64/amd64/locore.S
+++ b/sys/arch/amd64/amd64/locore.S
@@ -1,4 +1,4 @@
-/*     $OpenBSD: locore.S,v 1.63 2015/03/22 05:55:39 guenther Exp $    */
+/*     $OpenBSD: locore.S,v 1.64 2015/04/18 05:14:05 guenther Exp $    */
 /*     $NetBSD: locore.S,v 1.13 2004/03/25 18:33:17 drochner Exp $     */
 
 /*
@@ -1024,7 +1024,7 @@ IDTVEC(syscall)
        movq    %r11, TF_RFLAGS(%rsp)   /* old rflags from syscall insn */
        movq    $(GSEL(GUCODE_SEL, SEL_UPL)), TF_CS(%rsp)
        movq    %rcx,TF_RIP(%rsp)
-       movq    $2,TF_ERR(%rsp)
+       movq    $2,TF_ERR(%rsp)         /* ignored */
        movq    $T_ASTFLT, TF_TRAPNO(%rsp)
 
        movq    CPUVAR(CURPROC),%r14

diff --git a/sys/arch/amd64/amd64/trap.c b/sys/arch/amd64/amd64/trap.c
index 473273c..3c45279 100644 (file)
--- a/sys/arch/amd64/amd64/trap.c
+++ b/sys/arch/amd64/amd64/trap.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: trap.c,v 1.44 2015/03/14 03:38:46 jsg Exp $   */
+/*     $OpenBSD: trap.c,v 1.45 2015/04/18 05:14:05 guenther Exp $      */
 /*     $NetBSD: trap.c,v 1.2 2003/05/04 23:51:56 fvdl Exp $    */
 
 /*-
@@ -562,12 +562,8 @@ syscall(struct trapframe *frame)
                frame->tf_rflags &= ~PSL_C;     /* carry bit */
                break;
        case ERESTART:
-               /*
-                * The offset to adjust the PC by depends on whether we entered
-                * the kernel through the trap or call gate.  We pushed the
-                * size of the instruction into tf_err on entry.
-                */
-               frame->tf_rip -= frame->tf_err;
+               /* Back up over the syscall instruction (2 bytes) */
+               frame->tf_rip -= 2;
                break;
        case EJUSTRETURN:
                /* nothing to do */

diff --git a/sys/arch/i386/i386/locore.s b/sys/arch/i386/i386/locore.s
index ed00082..81e61c7 100644 (file)
--- a/sys/arch/i386/i386/locore.s
+++ b/sys/arch/i386/i386/locore.s
@@ -1,4 +1,4 @@
-/*     $OpenBSD: locore.s,v 1.152 2015/04/12 18:37:53 mlarkin Exp $    */
+/*     $OpenBSD: locore.s,v 1.153 2015/04/18 05:14:05 guenther Exp $   */
 /*     $NetBSD: locore.s,v 1.145 1996/05/03 19:41:19 christos Exp $    */
 
 /*-
@@ -1491,7 +1491,7 @@ calltrap:
  * Trap gate entry for syscall
  */
 IDTVEC(syscall)
-       pushl   $2              # size of instruction for restart
+       pushl   $2              # ignored
        pushl   $T_ASTFLT       # trap # for doing ASTs
        INTRENTRY
        pushl   %esp

diff --git a/sys/arch/i386/i386/trap.c b/sys/arch/i386/i386/trap.c
index 5119002..e277cdf 100644 (file)
--- a/sys/arch/i386/i386/trap.c
+++ b/sys/arch/i386/i386/trap.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: trap.c,v 1.120 2015/01/11 19:34:52 guenther Exp $     */
+/*     $OpenBSD: trap.c,v 1.121 2015/04/18 05:14:05 guenther Exp $     */
 /*     $NetBSD: trap.c,v 1.95 1996/05/05 06:50:02 mycroft Exp $        */
 
 /*-
@@ -531,7 +531,7 @@ syscall(struct trapframe *frame)
        caddr_t params;
        struct sysent *callp;
        struct proc *p;
-       int error, opc, nsys;
+       int error, nsys;
        register_t code, args[8], rval[2];
 #ifdef DIAGNOSTIC
        int ocpl = lapic_tpr;
@@ -545,7 +545,6 @@ syscall(struct trapframe *frame)
 #endif
        p = curproc;
        p->p_md.md_regs = frame;
-       opc = frame->tf_eip;
        code = frame->tf_eax;
 
        nsys = p->p_p->ps_emul->e_nsysent;
@@ -640,12 +639,8 @@ syscall(struct trapframe *frame)
                frame->tf_eflags &= ~PSL_C;     /* carry bit */
                break;
        case ERESTART:
-               /*
-                * The offset to adjust the PC by depends on whether we entered
-                * the kernel through the trap or call gate.  We pushed the
-                * size of the instruction into tf_err on entry.
-                */
-               frame->tf_eip = opc - frame->tf_err;
+               /* Back up over the int$80 (2 bytes) that made the syscall */
+               frame->tf_eip -= 2;
                break;
        case EJUSTRETURN:
                /* nothing to do */