fork: return value in child

Due to exiting on different stack than current's thread in fork in child the return value was not set by threads_setupUserReturn. JIRA: RTOS-979
phoenix-rtos · Nov 29, 2024 · 08999da · 08999da
1 parent 07519a2
commit 08999da
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Showing 17 changed files with 47 additions and 47 deletions.
diff --git a/hal/armv7a/_interrupts.S b/hal/armv7a/_interrupts.S
@@ -259,31 +259,29 @@ _interrupts_dispatch:
 .type _syscalls_dispatch, %function
 _syscalls_dispatch:
 	stmfd sp, {r0-r4}^
-	sub r1, sp, #0x14
+	sub r2, sp, #0x14
 	mrs r3, spsr
-	mov r2, lr
+	mov r1, lr
 	tst r3, #THUMB_STATE
-	ldreq r0, [r2, #-4]
+	ldreq r0, [r1, #-4]
 	biceq r0, r0, #0xff000000
-	ldrneh r0, [r2, #-2]
+	ldrneh r0, [r1, #-2]
 	bicne r0, r0, #0xff00
 	mrc p15, 0, r4, c13, c0, 4 /* TPIDRPRW */
 
 	cpsie af, #SYS_MODE
 
 	/* Store CPU state onto kernel stack */
-	stmfd r4!, {r2}
+	stmfd r4!, {r1}
 	stmfd r4!, {r5-r14}
-	mov r2, sp
+	mov r1, sp
 	mov sp, r4
-	ldmfd r1, {r4-r8}
+	ldmfd r2, {r4-r8}
 	push {r3-r8}
 	push_fpu_state r4
-	sub r1, sp, #8
-	push {r1}
-	push {r1}
-
-	mov r1, r2
+	sub r2, sp, #8
+	push {r2}
+	push {r2}
 
 	cpsie if
 

diff --git a/hal/armv7a/exceptions.c b/hal/armv7a/exceptions.c
@@ -116,7 +116,7 @@ static void exceptions_defaultHandler(unsigned int n, exc_context_t *ctx)
 }
 
 
-extern void threads_setupUserReturn(void *retval);
+extern void threads_setupUserReturn(void *retval, cpu_context_t *ctx);
 
 
 void exceptions_dispatch(unsigned int n, exc_context_t *ctx)
@@ -130,7 +130,7 @@ void exceptions_dispatch(unsigned int n, exc_context_t *ctx)
 
 	/* Handle signals if necessary */
 	if (hal_cpuSupervisorMode(&ctx->cpuCtx) == 0) {
-		threads_setupUserReturn((void *)ctx->cpuCtx.r0);
+		threads_setupUserReturn((void *)ctx->cpuCtx.r0, &ctx->cpuCtx);
 	}
 }
 

diff --git a/hal/armv7m/imxrt/_init.S b/hal/armv7m/imxrt/_init.S
@@ -128,7 +128,6 @@ _syscall_dispatch:
 	str r12, [sp, #8] /* ustack */
 
 	/* At this point full context is saved on kernel stack */
-	add r2, sp, #(38 * 4)
 	str sp, [r6]
 	isb
 	dmb
@@ -139,6 +138,7 @@ _syscall_dispatch:
 
 	stmdb r0!, {r1-r4}
 
+	mov r2, sp
 	sub sp, sp, #(18 * 4)
 
 	mov r1, r0

diff --git a/hal/armv7m/stm32/_init.S b/hal/armv7m/stm32/_init.S
@@ -127,6 +127,7 @@ _syscall_dispatch:
 	/* Copy arguments back to the user stack */
 	stmdb r0!, {r1-r4}
 	mov r1, r0
+	mov r2, sp
 	ldrb r0, [r7, #-3]
 
 	/* Prepare pseudo context */

diff --git a/hal/armv8m/mcx/_init.S b/hal/armv8m/mcx/_init.S
@@ -125,6 +125,7 @@ _syscall_dispatch:
 	/* Copy arguments back to the user stack */
 	stmdb r0!, {r1-r4}
 	mov r1, r0
+	mov r2, sp
 	ldrb r0, [r7, #-3]
 
 	/* Prepare pseudo context */

diff --git a/hal/armv8m/nrf/_init.S b/hal/armv8m/nrf/_init.S
@@ -125,6 +125,7 @@ _syscall_dispatch:
 	/* Copy arguments back to the user stack */
 	stmdb r0!, {r1-r4}
 	mov r1, r0
+	mov r2, sp
 	ldrb r0, [r7, #-3]
 
 	/* Prepare pseudo context */

diff --git a/hal/armv8r/_interrupts.S b/hal/armv8r/_interrupts.S
@@ -259,31 +259,29 @@ _interrupts_dispatch:
 .type _syscalls_dispatch, %function
 _syscalls_dispatch:
 	stmfd sp, {r0-r4}^
-	sub r1, sp, #0x14
+	sub r2, sp, #0x14
 	mrs r3, spsr
-	mov r2, lr
+	mov r1, lr
 	tst r3, #THUMB_STATE
-	ldreq r0, [r2, #-4]
+	ldreq r0, [r1, #-4]
 	biceq r0, r0, #0xff000000
-	ldrneh r0, [r2, #-2]
+	ldrneh r0, [r1, #-2]
 	bicne r0, r0, #0xff00
 	mrc p15, 0, r4, c13, c0, 4 /* TPIDRPRW */
 
 	cpsie af, #MODE_SYS
 
 	/* Store CPU state onto kernel stack */
-	stmfd r4!, {r2}
+	stmfd r4!, {r1}
 	stmfd r4!, {r5-r14}
-	mov r2, sp
+	mov r1, sp
 	mov sp, r4
-	ldmfd r1, {r4-r8}
+	ldmfd r2, {r4-r8}
 	push {r3-r8}
 	push_fpu_state r4
-	sub r1, sp, #8
-	push {r1}
-	push {r1}
-
-	mov r1, r2
+	sub r2, sp, #8
+	push {r2}
+	push {r2}
 
 	cpsie if
 

diff --git a/hal/armv8r/exceptions.c b/hal/armv8r/exceptions.c
@@ -118,7 +118,7 @@ static void exceptions_defaultHandler(unsigned int n, exc_context_t *ctx)
 }
 
 
-extern void threads_setupUserReturn(void *retval);
+extern void threads_setupUserReturn(void *retval, cpu_context_t *ctx);
 
 
 void exceptions_dispatch(unsigned int n, exc_context_t *ctx)
@@ -135,7 +135,7 @@ void exceptions_dispatch(unsigned int n, exc_context_t *ctx)
 
 	/* Handle signals if necessary */
 	if (hal_cpuSupervisorMode(&ctx->cpuCtx) == 0) {
-		threads_setupUserReturn((void *)ctx->cpuCtx.r0);
+		threads_setupUserReturn((void *)ctx->cpuCtx.r0, &ctx->cpuCtx);
 	}
 }
 

diff --git a/hal/ia32/_exceptions.S b/hal/ia32/_exceptions.S
@@ -162,11 +162,14 @@ sym:
 	addl $4, %esp;\
 	testl %eax, %eax;\
 	jnz exception_popContext;\
+	/* cpu_context_t */;\
+	leal 28(%esp), %eax;\
 	/* return value */ ;\
-	movl 56(%esp), %eax;\
+	movl 56(%esp), %ebx;\
 	pushl %eax;\
+	pushl %ebx;\
 	call threads_setupUserReturn;\
-	addl $4, %esp;\
+	addl $8, %esp;\
 	;\
 	jmp exception_popContext
 

diff --git a/hal/ia32/_interrupts.S b/hal/ia32/_interrupts.S
@@ -209,13 +209,13 @@ _interrupts_syscall:
 	movw %dx, %ds
 	movw %dx, %es
 	movl (4 * CTXPUSHL + 12)(%esp), %edx
+	pushl %esp
 	pushl %edx
 	pushl %eax
 	sti
 	call syscalls_dispatch
 	cli
-	addl $8, %esp
-	movl %eax, (4 * CTXPUSHL - EAX_OFFSET)(%esp)	/* Save return value to eax in context */
+	addl $12, %esp
 	jmp interrupts_popContextUnlocked
 .size _interrupts_syscall, .-_interrupts_syscall
 

diff --git a/hal/riscv64/_interrupts.S b/hal/riscv64/_interrupts.S
@@ -281,10 +281,9 @@ _interrupts_notIrq:
 	sd s2, 248(sp)
 	mv a0, a7      /* syscall number */
 	ld a1, 288(sp) /* ustack */
-
+	mv a2, sp
 	csrs sstatus, SSTATUS_SIE
 	call syscalls_dispatch
-	sd a0, 56(sp)
 	csrc sstatus, SSTATUS_SIE
 
 	tail _interrupts_returnUnlocked

diff --git a/hal/riscv64/exceptions.c b/hal/riscv64/exceptions.c
@@ -174,7 +174,7 @@ inline ptr_t hal_exceptionsPC(exc_context_t *ctx)
 }
 
 
-extern void threads_setupUserReturn(void *retval);
+extern void threads_setupUserReturn(void *retval, cpu_context_t *ctx);
 
 
 void exceptions_dispatch(unsigned int n, cpu_context_t *ctx)
@@ -195,7 +195,7 @@ void exceptions_dispatch(unsigned int n, cpu_context_t *ctx)
 
 	/* Handle signals if necessary */
 	if (hal_cpuSupervisorMode(ctx) == 0) {
-		threads_setupUserReturn((void *)ctx->a0);
+		threads_setupUserReturn((void *)ctx->a0, ctx);
 	}
 }
 

diff --git a/hal/sparcv8leon/_traps.S b/hal/sparcv8leon/_traps.S
@@ -684,9 +684,9 @@ s_fpu_done:
 	nop
 	nop
 
-	/* void *syscalls_dispatch(int n, char *ustack) */
+	/* void *syscalls_dispatch(int n, char *ustack, cpu_context_t *ctx) */
 	call syscalls_dispatch
-	nop
+	add %sp, 0x60, %sp
 
 	/* disable traps */
 #ifdef LEON3_USE_PWR

diff --git a/hal/sparcv8leon/exceptions.c b/hal/sparcv8leon/exceptions.c
@@ -153,7 +153,7 @@ __attribute__((noreturn)) static void exceptions_defaultHandler(unsigned int n,
 }
 
 
-extern void threads_setupUserReturn(void *retval);
+extern void threads_setupUserReturn(void *retval, cpu_context_t *ctx);
 
 
 void exceptions_dispatch(unsigned int n, exc_context_t *ctx)
@@ -167,7 +167,7 @@ void exceptions_dispatch(unsigned int n, exc_context_t *ctx)
 
 	/* Handle signals if necessary */
 	if (hal_cpuSupervisorMode(&ctx->cpuCtx) == 0) {
-		threads_setupUserReturn((void *)ctx->cpuCtx.o0);
+		threads_setupUserReturn((void *)ctx->cpuCtx.o0, &ctx->cpuCtx);
 	}
 }
 

diff --git a/proc/threads.c b/proc/threads.c
@@ -1482,10 +1482,10 @@ static int _threads_checkSignal(thread_t *selected, process_t *proc, cpu_context
 }
 
 
-void threads_setupUserReturn(void *retval)
+void threads_setupUserReturn(void *retval, cpu_context_t *ctx)
 {
 	spinlock_ctx_t sc;
-	cpu_context_t *ctx, *signalCtx;
+	cpu_context_t *signalCtx;
 	void *f;
 	void *kstackTop;
 	thread_t *thread;
@@ -1494,7 +1494,6 @@ void threads_setupUserReturn(void *retval)
 	thread = _proc_current();
 
 	kstackTop = thread->kstack + thread->kstacksz;
-	ctx = kstackTop - sizeof(*ctx);
 	signalCtx = (void *)((char *)hal_cpuGetUserSP(ctx) - sizeof(*signalCtx));
 	hal_cpuSetReturnValue(ctx, retval);
 

diff --git a/proc/threads.h b/proc/threads.h
@@ -211,7 +211,7 @@ extern int _threads_init(vm_map_t *kmap, vm_object_t *kernel);
 extern int threads_sigpost(process_t *process, thread_t *thread, int sig);
 
 
-extern void threads_setupUserReturn(void *retval);
+extern void threads_setupUserReturn(void *retval, cpu_context_t *ctx);
 
 
 #endif
diff --git a/syscalls.c b/syscalls.c
@@ -1854,7 +1854,7 @@ const void *const syscalls[] = { SYSCALLS(SYSCALLS_NAME) };
 const char *const syscall_strings[] = { SYSCALLS(SYSCALLS_STRING) };
 
 
-void *syscalls_dispatch(int n, char *ustack)
+void *syscalls_dispatch(int n, char *ustack, cpu_context_t *ctx)
 {
 	void *retval;
 
@@ -1868,7 +1868,7 @@ void *syscalls_dispatch(int n, char *ustack)
 		proc_threadEnd();
 	}
 
-	threads_setupUserReturn(retval);
+	threads_setupUserReturn(retval, ctx);
 
 	return retval;
 }