Fix signalcontext and makecontext.

3 files changed, 17 insertions, 14 deletions

diff --git a/lib/libc/arm/gen/_ctx_start.S b/lib/libc/arm/gen/_ctx_start.S
index 8187d74..fbde357 100644
--- a/lib/libc/arm/gen/_ctx_start.S
+++ b/lib/libc/arm/gen/_ctx_start.S
@@ -2,7 +2,8 @@
 
 .ident	"$FreeBSD$"
 ENTRY(_ctx_start)
-	mov	pc, r0
-	mov	r0, r1
+	mov	lr, pc
+	mov	pc, r4
+	mov	r0, r5
 	bl	_C_LABEL(ctx_done)
 	bl	_C_LABEL(abort)
diff --git a/lib/libc/arm/gen/makecontext.c b/lib/libc/arm/gen/makecontext.c
index 18aadf1..4fd3953 100644
--- a/lib/libc/arm/gen/makecontext.c
+++ b/lib/libc/arm/gen/makecontext.c
@@ -46,7 +46,7 @@ __FBSDID("$FreeBSD$");
 
 #include <stdarg.h>
 
-extern void _ctx_start(ucontext_t *, int argc, ...);
+extern void _ctx_start(void);
 
 void
 ctx_done(ucontext_t *ucp)
@@ -72,7 +72,8 @@ __makecontext(ucontext_t *ucp, void (*func)(void), int argc, ...)
 
 	/* Compute and align stack pointer. */
 	sp = (unsigned int *)
-	    (((uintptr_t)ucp->uc_stack.ss_sp + ucp->uc_stack.ss_size) & ~7);
+	    (((uintptr_t)ucp->uc_stack.ss_sp + ucp->uc_stack.ss_size -
+	      sizeof(double)) & ~7);
 	/* Allocate necessary stack space for arguments exceeding r0-3. */
 	if (argc > 4)
 		sp -= argc - 4;
@@ -80,8 +81,9 @@ __makecontext(ucontext_t *ucp, void (*func)(void), int argc, ...)
 	/* Wipe out frame pointer. */
 	gr[_REG_FP] = 0;
 	/* Arrange for return via the trampoline code. */
-	gr[_REG_LR] = (__greg_t)_ctx_start;
-	gr[_REG_PC] = (__greg_t)func;
+	gr[_REG_PC] = (__greg_t)_ctx_start;
+	gr[_REG_R4] = (__greg_t)func;
+	gr[_REG_R5] = (__greg_t)ucp;
 
 	va_start(ap, argc);
 	/* Pass up to four arguments in r0-3. */
diff --git a/lib/libc/arm/gen/signalcontext.c b/lib/libc/arm/gen/signalcontext.c
index 35108fd..bb9a54d 100644
--- a/lib/libc/arm/gen/signalcontext.c
+++ b/lib/libc/arm/gen/signalcontext.c
@@ -51,11 +51,8 @@ __signalcontext(ucontext_t *ucp, int sig, __sighandler_t *func)
 	struct sigframe *sfp;
 	__greg_t *gr = ucp->uc_mcontext.__gregs;
 	unsigned int *sp;
-	mcontext_t *mc;
 
-	mc = &ucp->uc_mcontext;
-	sp = (unsigned int *)
-	    (((uintptr_t)ucp->uc_stack.ss_sp + ucp->uc_stack.ss_size) & ~7);
+	sp = (unsigned int *)gr[_REG_SP];
 
 	sfp = (struct sigframe *)sp - 1;
 	
@@ -63,13 +60,16 @@ __signalcontext(ucontext_t *ucp, int sig, __sighandler_t *func)
 	bcopy(ucp, &sfp->sf_uc, sizeof(*ucp));
 	sfp->sf_si.si_signo = sig;
 
-	gr[_REG_SP] = (__greg_t)sp;
+	gr[_REG_SP] = (__greg_t)sfp;
 	/* Wipe out frame pointer. */
 	gr[_REG_FP] = 0;
 	/* Arrange for return via the trampoline code. */
-	gr[_REG_LR] = (__greg_t)_ctx_start;
-	gr[_REG_PC] = (__greg_t)func;
-	gr[_REG_R0] = (__greg_t)ucp;
+	gr[_REG_PC] = (__greg_t)_ctx_start;
+	gr[_REG_R4] = (__greg_t)func;
+	gr[_REG_R5] = (__greg_t)ucp;
+	gr[_REG_R0] = (__greg_t)sig;
+	gr[_REG_R1] = (__greg_t)&sfp->sf_si;
+	gr[_REG_R2] = (__greg_t)&sfp->sf_uc;
 
 	ucp->uc_link = &sfp->sf_uc;
 	sigdelset(&ucp->uc_sigmask, sig);