diff --git a/arch/arm/src/arm/arm_schedulesigaction.c b/arch/arm/src/arm/arm_schedulesigaction.c
index d1f40ffc2f7..ea831424f64 100644
--- a/arch/arm/src/arm/arm_schedulesigaction.c
+++ b/arch/arm/src/arm/arm_schedulesigaction.c
@@ -86,18 +86,15 @@
  *       currently executing task -- just call the signal
  *       handler now.
  *
+ * Assumptions:
+ *   Called from critical section
+ *
  ****************************************************************************/
 
 void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
 {
-  irqstate_t flags;
-
   sinfo("tcb=0x%p sigdeliver=0x%p\n", tcb, sigdeliver);
 
-  /* Make sure that interrupts are disabled */
-
-  flags = enter_critical_section();
-
   /* Refuse to handle nested signal actions */
 
   if (!tcb->xcp.sigdeliver)
@@ -184,6 +181,4 @@ void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
           tcb->xcp.regs[REG_CPSR]    = SVC_MODE | PSR_I_BIT | PSR_F_BIT;
         }
     }
-
-  leave_critical_section(flags);
 }
diff --git a/arch/arm/src/armv6-m/arm_schedulesigaction.c b/arch/arm/src/armv6-m/arm_schedulesigaction.c
index dfe8e117cb8..78f881f9b49 100644
--- a/arch/arm/src/armv6-m/arm_schedulesigaction.c
+++ b/arch/arm/src/armv6-m/arm_schedulesigaction.c
@@ -87,18 +87,15 @@
  *       currently executing task -- just call the signal
  *       handler now.
  *
+ * Assumptions:
+ *   Called from critical section
+ *
  ****************************************************************************/
 
 void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
 {
-  irqstate_t flags;
-
   sinfo("tcb=0x%p sigdeliver=0x%p\n", tcb, sigdeliver);
 
-  /* Make sure that interrupts are disabled */
-
-  flags = enter_critical_section();
-
   /* Refuse to handle nested signal actions */
 
   if (!tcb->xcp.sigdeliver)
@@ -194,6 +191,4 @@ void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
 #endif
         }
     }
-
-  leave_critical_section(flags);
 }
diff --git a/arch/arm/src/armv7-a/arm_schedulesigaction.c b/arch/arm/src/armv7-a/arm_schedulesigaction.c
index 8b44b32991a..cfe474df8d8 100644
--- a/arch/arm/src/armv7-a/arm_schedulesigaction.c
+++ b/arch/arm/src/armv7-a/arm_schedulesigaction.c
@@ -73,19 +73,16 @@
  *       currently executing task -- just call the signal
  *       handler now.
  *
+ * Assumptions:
+ *   Called from critical section
+ *
  ****************************************************************************/
 
 #ifndef CONFIG_SMP
 void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
 {
-  irqstate_t flags;
-
   sinfo("tcb=0x%p sigdeliver=0x%p\n", tcb, sigdeliver);
 
-  /* Make sure that interrupts are disabled */
-
-  flags = enter_critical_section();
-
   /* Refuse to handle nested signal actions */
 
   if (!tcb->xcp.sigdeliver)
@@ -180,24 +177,17 @@ void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
 #endif
         }
     }
-
-  leave_critical_section(flags);
 }
 #endif /* !CONFIG_SMP */
 
 #ifdef CONFIG_SMP
 void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
 {
-  irqstate_t flags;
   int cpu;
   int me;
 
   sinfo("tcb=0x%p sigdeliver=0x%p\n", tcb, sigdeliver);
 
-  /* Make sure that interrupts are disabled */
-
-  flags = enter_critical_section();
-
   /* Refuse to handle nested signal actions */
 
   if (!tcb->xcp.sigdeliver)
@@ -364,7 +354,5 @@ void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
 #endif
         }
     }
-
-  leave_critical_section(flags);
 }
 #endif /* CONFIG_SMP */
diff --git a/arch/arm/src/armv7-m/arm_schedulesigaction.c b/arch/arm/src/armv7-m/arm_schedulesigaction.c
index 73769392432..85ed00b6022 100644
--- a/arch/arm/src/armv7-m/arm_schedulesigaction.c
+++ b/arch/arm/src/armv7-m/arm_schedulesigaction.c
@@ -75,20 +75,17 @@
  *       currently executing task -- just call the signal
  *       handler now.
  *
+ * Assumptions:
+ *   Called from critical section
+ *
  ****************************************************************************/
 
 #ifndef CONFIG_SMP
 void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
 {
-  irqstate_t flags;
-
   sinfo("tcb=0x%p sigdeliver=0x%p\n", tcb, sigdeliver);
   DEBUGASSERT(tcb != NULL && sigdeliver != NULL);
 
-  /* Make sure that interrupts are disabled */
-
-  flags = enter_critical_section();
-
   /* Refuse to handle nested signal actions */
 
   if (tcb->xcp.sigdeliver == NULL)
@@ -203,24 +200,17 @@ void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
 #endif
         }
     }
-
-  leave_critical_section(flags);
 }
 #endif /* !CONFIG_SMP */
 
 #ifdef CONFIG_SMP
 void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
 {
-  irqstate_t flags;
   int cpu;
   int me;
 
   sinfo("tcb=0x%p sigdeliver=0x%p\n", tcb, sigdeliver);
 
-  /* Make sure that interrupts are disabled */
-
-  flags = enter_critical_section();
-
   /* Refuse to handle nested signal actions */
 
   if (!tcb->xcp.sigdeliver)
@@ -425,7 +415,5 @@ void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
 #endif
         }
     }
-
-  leave_critical_section(flags);
 }
 #endif /* CONFIG_SMP */
diff --git a/arch/arm/src/armv7-r/arm_schedulesigaction.c b/arch/arm/src/armv7-r/arm_schedulesigaction.c
index 5293e1370de..32f35130371 100644
--- a/arch/arm/src/armv7-r/arm_schedulesigaction.c
+++ b/arch/arm/src/armv7-r/arm_schedulesigaction.c
@@ -71,18 +71,15 @@
  *       currently executing task -- just call the signal
  *       handler now.
  *
+ * Assumptions:
+ *   Called from critical section
+ *
  ****************************************************************************/
 
 void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
 {
-  irqstate_t flags;
-
   sinfo("tcb=0x%p sigdeliver=0x%p\n", tcb, sigdeliver);
 
-  /* Make sure that interrupts are disabled */
-
-  flags = enter_critical_section();
-
   /* Refuse to handle nested signal actions */
 
   if (!tcb->xcp.sigdeliver)
@@ -178,6 +175,4 @@ void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
 #endif
         }
     }
-
-  leave_critical_section(flags);
 }
diff --git a/arch/arm/src/armv8-m/arm_schedulesigaction.c b/arch/arm/src/armv8-m/arm_schedulesigaction.c
index e48a9467ee4..d8352b94adc 100644
--- a/arch/arm/src/armv8-m/arm_schedulesigaction.c
+++ b/arch/arm/src/armv8-m/arm_schedulesigaction.c
@@ -75,20 +75,17 @@
  *       currently executing task -- just call the signal
  *       handler now.
  *
+ * Assumptions:
+ *   Called from critical section
+ *
  ****************************************************************************/
 
 #ifndef CONFIG_SMP
 void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
 {
-  irqstate_t flags;
-
   sinfo("tcb=0x%p sigdeliver=0x%p\n", tcb, sigdeliver);
   DEBUGASSERT(tcb != NULL && sigdeliver != NULL);
 
-  /* Make sure that interrupts are disabled */
-
-  flags = enter_critical_section();
-
   /* Refuse to handle nested signal actions */
 
   if (tcb->xcp.sigdeliver == NULL)
@@ -203,24 +200,17 @@ void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
 #endif
         }
     }
-
-  leave_critical_section(flags);
 }
 #endif /* !CONFIG_SMP */
 
 #ifdef CONFIG_SMP
 void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
 {
-  irqstate_t flags;
   int cpu;
   int me;
 
   sinfo("tcb=0x%p sigdeliver=0x%p\n", tcb, sigdeliver);
 
-  /* Make sure that interrupts are disabled */
-
-  flags = enter_critical_section();
-
   /* Refuse to handle nested signal actions */
 
   if (!tcb->xcp.sigdeliver)
@@ -429,7 +419,5 @@ void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
 #endif
         }
     }
-
-  leave_critical_section(flags);
 }
 #endif /* CONFIG_SMP */
diff --git a/arch/avr/src/avr/up_schedulesigaction.c b/arch/avr/src/avr/up_schedulesigaction.c
index 8bb45ad7bdd..6c25613fcfb 100644
--- a/arch/avr/src/avr/up_schedulesigaction.c
+++ b/arch/avr/src/avr/up_schedulesigaction.c
@@ -86,19 +86,17 @@
  *       currently executing task -- just call the signal
  *       handler now.
  *
+ * Assumptions:
+ *   Called from critical section
+ *
  ****************************************************************************/
 
 void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
 {
-  irqstate_t flags;
   uintptr_t reg_ptr = (uintptr_t)up_sigdeliver;
 
   sinfo("tcb=0x%p sigdeliver=0x%p\n", tcb, sigdeliver);
 
-  /* Make sure that interrupts are disabled */
-
-  flags = enter_critical_section();
-
   /* Refuse to handle nested signal actions */
 
   if (!tcb->xcp.sigdeliver)
@@ -209,6 +207,4 @@ void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
           tcb->xcp.regs[REG_SREG]  &= ~(1 << SREG_I);
         }
     }
-
-  leave_critical_section(flags);
 }
diff --git a/arch/avr/src/avr32/up_schedulesigaction.c b/arch/avr/src/avr32/up_schedulesigaction.c
index 3857191b41b..d5b037c14ae 100644
--- a/arch/avr/src/avr32/up_schedulesigaction.c
+++ b/arch/avr/src/avr32/up_schedulesigaction.c
@@ -86,18 +86,15 @@
  *       currently executing task -- just call the signal
  *       handler now.
  *
+ * Assumptions:
+ *   Called from critical section
+ *
  ****************************************************************************/
 
 void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
 {
-  irqstate_t flags;
-
   sinfo("tcb=0x%p sigdeliver=0x%p\n", tcb, sigdeliver);
 
-  /* Make sure that interrupts are disabled */
-
-  flags = enter_critical_section();
-
   /* Refuse to handle nested signal actions */
 
   if (!tcb->xcp.sigdeliver)
@@ -185,6 +182,4 @@ void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
           tcb->xcp.regs[REG_SR]    |= AVR32_SR_GM_MASK;
         }
     }
-
-  leave_critical_section(flags);
 }
diff --git a/arch/mips/src/mips32/mips_schedulesigaction.c b/arch/mips/src/mips32/mips_schedulesigaction.c
index 2f1b8688119..fd911b0a7ce 100644
--- a/arch/mips/src/mips32/mips_schedulesigaction.c
+++ b/arch/mips/src/mips32/mips_schedulesigaction.c
@@ -87,19 +87,17 @@
  *       currently executing task -- just call the signal
  *       handler now.
  *
+ * Assumptions:
+ *   Called from critical section
+ *
  ****************************************************************************/
 
 void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
 {
-  irqstate_t flags;
   uint32_t status;
 
   sinfo("tcb=0x%p sigdeliver=0x%p\n", tcb, sigdeliver);
 
-  /* Make sure that interrupts are disabled */
-
-  flags = enter_critical_section();
-
   /* Refuse to handle nested signal actions */
 
   if (!tcb->xcp.sigdeliver)
@@ -203,6 +201,4 @@ void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
                 tcb->xcp.regs[REG_EPC], tcb->xcp.regs[REG_STATUS]);
         }
     }
-
-  leave_critical_section(flags);
 }
diff --git a/arch/misoc/src/lm32/lm32_schedulesigaction.c b/arch/misoc/src/lm32/lm32_schedulesigaction.c
index 97effb3d5b5..b73d45dc8ff 100644
--- a/arch/misoc/src/lm32/lm32_schedulesigaction.c
+++ b/arch/misoc/src/lm32/lm32_schedulesigaction.c
@@ -90,18 +90,15 @@
  *       currently executing task -- just call the signal
  *       handler now.
  *
+ * Assumptions:
+ *   Called from critical section
+ *
  ****************************************************************************/
 
 void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
 {
-  irqstate_t flags;
-
   sinfo("tcb=0x%p sigdeliver=0x%p\n", tcb, sigdeliver);
 
-  /* Make sure that interrupts are disabled */
-
-  flags = enter_critical_section();
-
   /* Refuse to handle nested signal actions */
 
   if (!tcb->xcp.sigdeliver)
@@ -196,6 +193,4 @@ void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
                 tcb->xcp.regs[REG_EPC], tcb->xcp.regs[REG_STATUS]);
         }
     }
-
-  leave_critical_section(flags);
 }
diff --git a/arch/misoc/src/minerva/minerva_schedulesigaction.c b/arch/misoc/src/minerva/minerva_schedulesigaction.c
index 3f10ad3f775..ce66e18a003 100644
--- a/arch/misoc/src/minerva/minerva_schedulesigaction.c
+++ b/arch/misoc/src/minerva/minerva_schedulesigaction.c
@@ -91,18 +91,15 @@
  *       currently executing task -- just call the signal
  *       handler now.
  *
+ * Assumptions:
+ *   Called from critical section
+ *
  ****************************************************************************/
 
 void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
 {
-  irqstate_t flags;
-
   sinfo("tcb=0x%p sigdeliver=0x%p\n", tcb, sigdeliver);
 
-  /* Make sure that interrupts are disabled */
-
-  flags = enter_critical_section();
-
   /* Refuse to handle nested signal actions */
 
   if (!tcb->xcp.sigdeliver)
@@ -196,6 +193,4 @@ void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
                 tcb->xcp.regs[REG_CSR_MEPC], tcb->xcp.regs[REG_CSR_MSTATUS]);
         }
     }
-
-  leave_critical_section(flags);
 }
diff --git a/arch/or1k/src/common/up_schedulesigaction.c b/arch/or1k/src/common/up_schedulesigaction.c
index b6ef2207eeb..3f97afd289a 100644
--- a/arch/or1k/src/common/up_schedulesigaction.c
+++ b/arch/or1k/src/common/up_schedulesigaction.c
@@ -85,18 +85,15 @@
  *       currently executing task -- just call the signal
  *       handler now.
  *
+ * Assumptions:
+ *   Called from critical section
+ *
  ****************************************************************************/
 
 void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
 {
-  irqstate_t flags;
-
   sinfo("tcb=0x%p sigdeliver=0x%p\n", tcb, sigdeliver);
 
-  /* Make sure that interrupts are disabled */
-
-  flags = enter_critical_section();
-
   /* Refuse to handle nested signal actions */
 
   if (!tcb->xcp.sigdeliver)
@@ -188,6 +185,4 @@ void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
            */
         }
     }
-
-  leave_critical_section(flags);
 }
diff --git a/arch/renesas/src/m16c/m16c_schedulesigaction.c b/arch/renesas/src/m16c/m16c_schedulesigaction.c
index d0ce7e15bfb..d7a513fba6c 100644
--- a/arch/renesas/src/m16c/m16c_schedulesigaction.c
+++ b/arch/renesas/src/m16c/m16c_schedulesigaction.c
@@ -85,18 +85,15 @@
  *       currently executing task -- just call the signal
  *       handler now.
  *
+ * Assumptions:
+ *   Called from critical section
+ *
  ****************************************************************************/
 
 void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
 {
-  irqstate_t flags;
-
   sinfo("tcb=0x%p sigdeliver=0x%p\n", tcb, sigdeliver);
 
-  /* Make sure that interrupts are disabled */
-
-  flags = enter_critical_section();
-
   /* Refuse to handle nested signal actions */
 
   if (!tcb->xcp.sigdeliver)
@@ -181,6 +178,4 @@ void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
           tcb->xcp.regs[REG_FLG] &= ~M16C_FLG_I;
         }
     }
-
-  leave_critical_section(flags);
 }
diff --git a/arch/renesas/src/rx65n/rx65n_schedulesigaction.c b/arch/renesas/src/rx65n/rx65n_schedulesigaction.c
index 71da576e79b..045ee9e3cbd 100644
--- a/arch/renesas/src/rx65n/rx65n_schedulesigaction.c
+++ b/arch/renesas/src/rx65n/rx65n_schedulesigaction.c
@@ -70,18 +70,15 @@
  *       currently executing task -- just call the signal
  *       handler now.
  *
+ * Assumptions:
+ *   Called from critical section
+ *
  ****************************************************************************/
 
 void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
 {
-  irqstate_t flags;
-
   sinfo("tcb=0x%p sigdeliver=0x%p\n", tcb, sigdeliver);
 
-  /* Make sure that interrupts are disabled */
-
-  flags = enter_critical_section();
-
   /* Refuse to handle nested signal actions */
 
   if (!tcb->xcp.sigdeliver)
@@ -162,6 +159,4 @@ void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
           tcb->xcp.regs[REG_PSW]  |=  0x00030000;
         }
     }
-
-  leave_critical_section(flags);
 }
diff --git a/arch/renesas/src/sh1/sh1_schedulesigaction.c b/arch/renesas/src/sh1/sh1_schedulesigaction.c
index 54521a1efc2..311517db34f 100644
--- a/arch/renesas/src/sh1/sh1_schedulesigaction.c
+++ b/arch/renesas/src/sh1/sh1_schedulesigaction.c
@@ -85,18 +85,15 @@
  *       currently executing task -- just call the signal
  *       handler now.
  *
+ * Assumptions:
+ *   Called from critical section
+ *
  ****************************************************************************/
 
 void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
 {
-  irqstate_t flags;
-
   sinfo("tcb=0x%p sigdeliver=0x%p\n", tcb, sigdeliver);
 
-  /* Make sure that interrupts are disabled */
-
-  flags = enter_critical_section();
-
   /* Refuse to handle nested signal actions */
 
   if (!tcb->xcp.sigdeliver)
@@ -177,6 +174,4 @@ void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
           tcb->xcp.regs[REG_SR] |= 0x000000f0 ;
         }
     }
-
-  leave_critical_section(flags);
 }
diff --git a/arch/risc-v/src/gap8/gap8_schedulesigaction.c b/arch/risc-v/src/gap8/gap8_schedulesigaction.c
index 00b0601d42a..a194ebbdabf 100644
--- a/arch/risc-v/src/gap8/gap8_schedulesigaction.c
+++ b/arch/risc-v/src/gap8/gap8_schedulesigaction.c
@@ -90,11 +90,13 @@
  *       currently executing task -- just call the signal
  *       handler now.
  *
+ * Assumptions:
+ *   Called from critical section
+ *
  ****************************************************************************/
 
 void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
 {
-  irqstate_t flags;
   uint32_t int_ctx;
 
   sinfo("tcb=0x%p sigdeliver=0x%p\n", tcb, sigdeliver);
@@ -194,6 +196,4 @@ void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
                 tcb->xcp.regs[REG_EPC], tcb->xcp.regs[REG_STATUS]);
         }
     }
-
-  leave_critical_section(flags);
 }
diff --git a/arch/risc-v/src/nr5m100/nr5_schedulesigaction.c b/arch/risc-v/src/nr5m100/nr5_schedulesigaction.c
index 0614f72a29a..d1d3d64bae6 100644
--- a/arch/risc-v/src/nr5m100/nr5_schedulesigaction.c
+++ b/arch/risc-v/src/nr5m100/nr5_schedulesigaction.c
@@ -91,19 +91,17 @@
  *       currently executing task -- just call the signal
  *       handler now.
  *
+ * Assumptions:
+ *   Called from critical section
+ *
  ****************************************************************************/
 
 void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
 {
-  irqstate_t flags;
   uint32_t int_ctx;
 
   sinfo("tcb=0x%p sigdeliver=0x%p\n", tcb, sigdeliver);
 
-  /* Make sure that interrupts are disabled */
-
-  flags = enter_critical_section();
-
   /* Refuse to handle nested signal actions */
 
   if (!tcb->xcp.sigdeliver)
@@ -204,6 +202,4 @@ void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
                 tcb->xcp.regs[REG_EPC], tcb->xcp.regs[REG_STATUS]);
         }
     }
-
-  leave_critical_section(flags);
 }
diff --git a/arch/risc-v/src/rv32im/riscv_schedulesigaction.c b/arch/risc-v/src/rv32im/riscv_schedulesigaction.c
index a256a102c97..e2b4ffc4767 100644
--- a/arch/risc-v/src/rv32im/riscv_schedulesigaction.c
+++ b/arch/risc-v/src/rv32im/riscv_schedulesigaction.c
@@ -71,19 +71,17 @@
  *       currently executing task -- just call the signal
  *       handler now.
  *
+ * Assumptions:
+ *   Called from critical section
+ *
  ****************************************************************************/
 
 void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
 {
-  irqstate_t flags;
   uint32_t int_ctx;
 
   sinfo("tcb=0x%p sigdeliver=0x%p\n", tcb, sigdeliver);
 
-  /* Make sure that interrupts are disabled */
-
-  flags = enter_critical_section();
-
   /* Refuse to handle nested signal actions */
 
   if (!tcb->xcp.sigdeliver)
@@ -189,7 +187,5 @@ void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
                 tcb->xcp.regs[REG_EPC], tcb->xcp.regs[REG_INT_CTX]);
         }
     }
-
-  leave_critical_section(flags);
 }
 
diff --git a/arch/risc-v/src/rv64gc/riscv_schedulesigaction.c b/arch/risc-v/src/rv64gc/riscv_schedulesigaction.c
index d789cb0f513..bba4a535142 100644
--- a/arch/risc-v/src/rv64gc/riscv_schedulesigaction.c
+++ b/arch/risc-v/src/rv64gc/riscv_schedulesigaction.c
@@ -88,20 +88,18 @@
  *       currently executing task -- just call the signal
  *       handler now.
  *
+ * Assumptions:
+ *   Called from critical section
+ *
  ****************************************************************************/
 
 #ifndef CONFIG_SMP
 void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
 {
-  irqstate_t flags;
   uint64_t int_ctx;
 
   sinfo("tcb=0x%p sigdeliver=0x%p\n", tcb, sigdeliver);
 
-  /* Make sure that interrupts are disabled */
-
-  flags = enter_critical_section();
-
   /* Refuse to handle nested signal actions */
 
   if (!tcb->xcp.sigdeliver)
@@ -212,25 +210,18 @@ void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
                 tcb->xcp.regs[REG_EPC], tcb->xcp.regs[REG_INT_CTX]);
         }
     }
-
-  leave_critical_section(flags);
 }
 #endif /* !CONFIG_SMP */
 
 #ifdef CONFIG_SMP
 void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
 {
-  irqstate_t flags;
   uint64_t int_ctx;
   int cpu;
   int me;
 
   sinfo("tcb=0x%p sigdeliver=0x%p\n", tcb, sigdeliver);
 
-  /* Make sure that interrupts are disabled */
-
-  flags = enter_critical_section();
-
   /* Refuse to handle nested signal actions */
 
   if (!tcb->xcp.sigdeliver)
@@ -401,7 +392,5 @@ void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
           tcb->xcp.regs[REG_INT_CTX]  = int_ctx;
         }
     }
-
-  leave_critical_section(flags);
 }
 #endif /* CONFIG_SMP */
diff --git a/arch/sim/src/sim/up_schedulesigaction.c b/arch/sim/src/sim/up_schedulesigaction.c
index b95d10e75e7..4466ae70a9c 100644
--- a/arch/sim/src/sim/up_schedulesigaction.c
+++ b/arch/sim/src/sim/up_schedulesigaction.c
@@ -82,6 +82,9 @@
  *       currently executing task -- just call the signal
  *       handler now.
  *
+ * Assumptions:
+ *   Called from critical section
+ *
  ****************************************************************************/
 
 void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
diff --git a/arch/x86/src/i486/up_schedulesigaction.c b/arch/x86/src/i486/up_schedulesigaction.c
index e8812516268..f8289cf8df6 100644
--- a/arch/x86/src/i486/up_schedulesigaction.c
+++ b/arch/x86/src/i486/up_schedulesigaction.c
@@ -81,18 +81,15 @@
  *   (3) If not in an interrupt handler and the tcb IS the currently
  *       executing task -- just call the signal handler now.
  *
+ * Assumptions:
+ *   Called from critical section
+ *
  ****************************************************************************/
 
 void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
 {
-  irqstate_t flags;
-
   sinfo("tcb=0x%p sigdeliver=0x%p\n", tcb, sigdeliver);
 
-  /* Make sure that interrupts are disabled */
-
-  flags = enter_critical_section();
-
   /* Refuse to handle nested signal actions */
 
   if (!tcb->xcp.sigdeliver)
@@ -178,6 +175,4 @@ void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
           tcb->xcp.regs[REG_EFLAGS]  = 0;
         }
     }
-
-  leave_critical_section(flags);
 }
diff --git a/arch/x86_64/src/intel64/up_schedulesigaction.c b/arch/x86_64/src/intel64/up_schedulesigaction.c
index 5bb2848d070..76227ac3ff7 100644
--- a/arch/x86_64/src/intel64/up_schedulesigaction.c
+++ b/arch/x86_64/src/intel64/up_schedulesigaction.c
@@ -80,19 +80,16 @@
  *   (3) If not in an interrupt handler and the tcb IS the currently
  *       executing task -- just call the signal handler now.
  *
+ * Assumptions:
+ *   Called from critical section
+ *
  ****************************************************************************/
 
 void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
 {
-  irqstate_t flags;
-
   sinfo("tcb=0x%p sigdeliver=0x%p\n", tcb, sigdeliver);
   sinfo("rtcb=0x%p g_current_regs=0x%p\n", this_task(), g_current_regs);
 
-  /* Make sure that interrupts are disabled */
-
-  flags = enter_critical_section();
-
   /* Refuse to handle nested signal actions */
 
   if (!tcb->xcp.sigdeliver)
@@ -178,8 +175,6 @@ void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
           tcb->xcp.regs[REG_RFLAGS]  = 0;
         }
     }
-
-  leave_critical_section(flags);
 }
 
 #endif /* !CONFIG_DISABLE_SIGNALS */
diff --git a/arch/xtensa/src/common/xtensa_schedsigaction.c b/arch/xtensa/src/common/xtensa_schedsigaction.c
index 62f4bfd0978..838ea6b7281 100644
--- a/arch/xtensa/src/common/xtensa_schedsigaction.c
+++ b/arch/xtensa/src/common/xtensa_schedsigaction.c
@@ -86,19 +86,16 @@
  *       currently executing task -- just call the signal
  *       handler now.
  *
+ * Assumptions:
+ *   Called from critical section
+ *
  ****************************************************************************/
 
 #ifndef CONFIG_SMP
 void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
 {
-  irqstate_t flags;
-
   sinfo("tcb=0x%p sigdeliver=0x%p\n", tcb, sigdeliver);
 
-  /* Make sure that interrupts are disabled */
-
-  flags = enter_critical_section();
-
   /* Refuse to handle nested signal actions */
 
   if (!tcb->xcp.sigdeliver)
@@ -200,24 +197,17 @@ void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
 #endif
         }
     }
-
-  leave_critical_section(flags);
 }
 #endif /* !CONFIG_SMP */
 
 #ifdef CONFIG_SMP
 void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
 {
-  irqstate_t flags;
   int cpu;
   int me;
 
   sinfo("tcb=0x%p sigdeliver=0x%p\n", tcb, sigdeliver);
 
-  /* Make sure that interrupts are disabled */
-
-  flags = enter_critical_section();
-
   /* Refuse to handle nested signal actions */
 
   if (!tcb->xcp.sigdeliver)
@@ -393,7 +383,5 @@ void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
 #endif
         }
     }
-
-  leave_critical_section(flags);
 }
 #endif /* CONFIG_SMP */
diff --git a/arch/z16/src/common/z16_schedulesigaction.c b/arch/z16/src/common/z16_schedulesigaction.c
index 64120cfb6b2..49f4266907f 100644
--- a/arch/z16/src/common/z16_schedulesigaction.c
+++ b/arch/z16/src/common/z16_schedulesigaction.c
@@ -69,18 +69,15 @@
  *       currently executing task -- just call the signal
  *       handler now.
  *
+ * Assumptions:
+ *   Called from critical section
+ *
  ****************************************************************************/
 
 void up_schedule_sigaction(FAR struct tcb_s *tcb, sig_deliver_t sigdeliver)
 {
-  irqstate_t flags;
-
   sinfo("tcb=0x%p sigdeliver=0x%06x\n", tcb, (uint32_t)sigdeliver);
 
-  /* Make sure that interrupts are disabled */
-
-  flags = enter_critical_section();
-
   /* Refuse to handle nested signal actions */
 
   if (!tcb->xcp.sigdeliver)
@@ -165,6 +162,4 @@ void up_schedule_sigaction(FAR struct tcb_s *tcb, sig_deliver_t sigdeliver)
           tcb->xcp.regs[REG_FLAGS] = 0;
         }
     }
-
-  leave_critical_section(flags);
 }
diff --git a/arch/z80/src/ez80/ez80_schedulesigaction.c b/arch/z80/src/ez80/ez80_schedulesigaction.c
index b18abb732fa..47d7e50fe15 100644
--- a/arch/z80/src/ez80/ez80_schedulesigaction.c
+++ b/arch/z80/src/ez80/ez80_schedulesigaction.c
@@ -95,18 +95,15 @@ static void ez80_sigsetup(FAR struct tcb_s *tcb, sig_deliver_t sigdeliver,
  *       currently executing task -- just call the signal
  *       handler now.
  *
+ * Assumptions:
+ *   Called from critical section
+ *
  ****************************************************************************/
 
 void up_schedule_sigaction(FAR struct tcb_s *tcb, sig_deliver_t sigdeliver)
 {
-  irqstate_t flags;
-
   sinfo("tcb=0x%p sigdeliver=0x%04x\n", tcb, (uint16_t)sigdeliver);
 
-  /* Make sure that interrupts are disabled */
-
-  flags = enter_critical_section();
-
   /* Refuse to handle nested signal actions */
 
   if (tcb->xcp.sigdeliver == NULL)
@@ -162,6 +159,4 @@ void up_schedule_sigaction(FAR struct tcb_s *tcb, sig_deliver_t sigdeliver)
           ez80_sigsetup(tcb, sigdeliver, tcb->xcp.regs);
         }
     }
-
-  leave_critical_section(flags);
 }
diff --git a/arch/z80/src/z180/z180_schedulesigaction.c b/arch/z80/src/z180/z180_schedulesigaction.c
index 8d185712d84..4a95855ce82 100644
--- a/arch/z80/src/z180/z180_schedulesigaction.c
+++ b/arch/z80/src/z180/z180_schedulesigaction.c
@@ -113,18 +113,15 @@ static void z180_sigsetup(FAR struct tcb_s *tcb, sig_deliver_t sigdeliver,
  *       currently executing task -- just call the signal
  *       handler now.
  *
+ * Assumptions:
+ *   Called from critical section
+ *
  ****************************************************************************/
 
 void up_schedule_sigaction(FAR struct tcb_s *tcb, sig_deliver_t sigdeliver)
 {
-  irqstate_t flags;
-
   _info("tcb=0x%p sigdeliver=0x%04x\n", tcb, (uint16_t)sigdeliver);
 
-  /* Make sure that interrupts are disabled */
-
-  flags = enter_critical_section();
-
   /* Refuse to handle nested signal actions */
 
   if (tcb->xcp.sigdeliver == NULL)
@@ -181,6 +178,4 @@ void up_schedule_sigaction(FAR struct tcb_s *tcb, sig_deliver_t sigdeliver)
           z180_sigsetup(tcb, sigdeliver, tcb->xcp.regs);
         }
     }
-
-  leave_critical_section(flags);
 }
diff --git a/arch/z80/src/z8/z8_schedulesigaction.c b/arch/z80/src/z8/z8_schedulesigaction.c
index 5825b8537d1..3127e235216 100644
--- a/arch/z80/src/z8/z8_schedulesigaction.c
+++ b/arch/z80/src/z8/z8_schedulesigaction.c
@@ -110,18 +110,15 @@ static void z8_sigsetup(FAR struct tcb_s *tcb, sig_deliver_t sigdeliver,
  *       currently executing task -- just call the signal
  *       handler now.
  *
+ * Assumptions:
+ *   Called from critical section
+ *
  ****************************************************************************/
 
 void up_schedule_sigaction(FAR struct tcb_s *tcb, sig_deliver_t sigdeliver)
 {
-  irqstate_t flags;
-
   sinfo("tcb=0x%p sigdeliver=0x%04x\n", tcb, (uint16_t)sigdeliver);
 
-  /* Make sure that interrupts are disabled */
-
-  flags = enter_critical_section();
-
   /* Refuse to handle nested signal actions */
 
   if (tcb->xcp.sigdeliver == NULL)
@@ -180,6 +177,4 @@ void up_schedule_sigaction(FAR struct tcb_s *tcb, sig_deliver_t sigdeliver)
           z8_sigsetup(tcb, sigdeliver, tcb->xcp.regs);
         }
     }
-
-  leave_critical_section(flags);
 }
diff --git a/arch/z80/src/z80/z80_schedulesigaction.c b/arch/z80/src/z80/z80_schedulesigaction.c
index 657ef6fb3ef..87d1ebb3d96 100644
--- a/arch/z80/src/z80/z80_schedulesigaction.c
+++ b/arch/z80/src/z80/z80_schedulesigaction.c
@@ -111,18 +111,15 @@ static void z80_sigsetup(FAR struct tcb_s *tcb, sig_deliver_t sigdeliver,
  *       currently executing task -- just call the signal
  *       handler now.
  *
+ * Assumptions:
+ *   Called from critical section
+ *
  ****************************************************************************/
 
 void up_schedule_sigaction(FAR struct tcb_s *tcb, sig_deliver_t sigdeliver)
 {
-  irqstate_t flags;
-
   _info("tcb=0x%p sigdeliver=0x%04x\n", tcb, (uint16_t)sigdeliver);
 
-  /* Make sure that interrupts are disabled */
-
-  flags = enter_critical_section();
-
   /* Refuse to handle nested signal actions */
 
   if (tcb->xcp.sigdeliver == NULL)
@@ -179,6 +176,4 @@ void up_schedule_sigaction(FAR struct tcb_s *tcb, sig_deliver_t sigdeliver)
           z80_sigsetup(tcb, sigdeliver, tcb->xcp.regs);
         }
     }
-
-  leave_critical_section(flags);
 }