protected build: userspace threads will unexpectly work in privileged mode after syscall

In protected build mode, the syscall returns without setting correct value for the CONTROL register, which causes the userspace threads working in privileged mode after syscall.

Signed-off-by: pangzhen1 <[email protected]>

Author: pangzhen1xiaomi

arch/arm/include/armv6-m/irq.h

@@ -142,6 +142,7 @@ struct xcpt_syscall_s
 {
   uint32_t excreturn;   /* The EXC_RETURN value */
   uint32_t sysreturn;   /* The return PC */
+  uint32_t ctrlreturn;  /* The return CONTROL value */
 };
 #endif
 

arch/arm/include/armv7-m/irq.h

@@ -202,6 +202,7 @@ struct xcpt_syscall_s
 {
   uint32_t excreturn;   /* The EXC_RETURN value */
   uint32_t sysreturn;   /* The return PC */
+  uint32_t ctrlreturn;  /* The return CONTROL value */
 };
 #endif
 

arch/arm/include/armv8-m/irq.h

@@ -213,6 +213,7 @@ struct xcpt_syscall_s
 {
   uint32_t excreturn;   /* The EXC_RETURN value */
   uint32_t sysreturn;   /* The return PC */
+  uint32_t ctrlreturn;  /* The return CONTROL value */
 };
 #endif
 

arch/arm/src/armv6-m/arm_svcall.c

@@ -224,6 +224,7 @@ int arm_svcall(int irq, void *context, void *arg)
 
           regs[REG_PC]         = rtcb->xcp.syscall[index].sysreturn;
           regs[REG_EXC_RETURN] = rtcb->xcp.syscall[index].excreturn;
+          regs[REG_CONTROL]    = rtcb->xcp.syscall[index].ctrlreturn;
           rtcb->xcp.nsyscalls  = index;
 
           /* The return value must be in R0-R1.  dispatch_syscall()
@@ -417,6 +418,7 @@ int arm_svcall(int irq, void *context, void *arg)
 
           rtcb->xcp.syscall[index].sysreturn  = regs[REG_PC];
           rtcb->xcp.syscall[index].excreturn  = regs[REG_EXC_RETURN];
+          rtcb->xcp.syscall[index].ctrlreturn = regs[REG_CONTROL];
           rtcb->xcp.nsyscalls  = index + 1;
 
           regs[REG_PC]         = (uint32_t)dispatch_syscall;

arch/arm/src/armv7-m/arm_svcall.c

@@ -233,6 +233,7 @@ int arm_svcall(int irq, void *context, void *arg)
 
           regs[REG_PC]         = rtcb->xcp.syscall[index].sysreturn;
           regs[REG_EXC_RETURN] = rtcb->xcp.syscall[index].excreturn;
+          regs[REG_CONTROL]    = rtcb->xcp.syscall[index].ctrlreturn;
           rtcb->xcp.nsyscalls  = index;
 
           /* The return value must be in R0-R1.  dispatch_syscall()
@@ -426,6 +427,7 @@ int arm_svcall(int irq, void *context, void *arg)
 
           rtcb->xcp.syscall[index].sysreturn  = regs[REG_PC];
           rtcb->xcp.syscall[index].excreturn  = regs[REG_EXC_RETURN];
+          rtcb->xcp.syscall[index].ctrlreturn = regs[REG_CONTROL];
           rtcb->xcp.nsyscalls  = index + 1;
 
           regs[REG_PC]         = (uint32_t)dispatch_syscall & ~1;

arch/arm/src/armv8-m/arm_svcall.c

@@ -232,6 +232,7 @@ int arm_svcall(int irq, void *context, void *arg)
 
           regs[REG_PC]         = rtcb->xcp.syscall[index].sysreturn;
           regs[REG_EXC_RETURN] = rtcb->xcp.syscall[index].excreturn;
+          regs[REG_CONTROL]    = rtcb->xcp.syscall[index].ctrlreturn;
           rtcb->xcp.nsyscalls  = index;
 
           /* The return value must be in R0-R1.  dispatch_syscall()
@@ -427,6 +428,7 @@ int arm_svcall(int irq, void *context, void *arg)
 
           rtcb->xcp.syscall[index].sysreturn  = regs[REG_PC];
           rtcb->xcp.syscall[index].excreturn  = regs[REG_EXC_RETURN];
+          rtcb->xcp.syscall[index].ctrlreturn = regs[REG_CONTROL];
           rtcb->xcp.nsyscalls  = index + 1;
 
           regs[REG_PC]         = (uint32_t)dispatch_syscall & ~1;