xen/arm: domain: Fix MISRA C 2012 Rule 8.7 violation

The function idle_loop() is referenced only in domain.c.
Change its linkage from external to internal by adding the storage-class
specifier static to its definitions.

Add the function as a 'fake' input operand to the inline assembly statement,
to make the compiler aware that the function is used.
Fake means that the function is not actually used as an operand by the asm code.
That is because there is not a suitable gcc arm32 asm constraint for labels.

Declare return_to_new_vcpu32() and return_to_new_vcpu64() that are also
referenced by this inline asm statement.

Also, this patch resolves indirectly a MISRA C 2012 Rule 8.4 violation warning.

Signed-off-by: Xenia Ragiadakou <burzalodowa@gmail.com>
[add noreturn]
Signed-off-by: Stefano Stabellini <stefano.stabellini@amd.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Bertrand Marquis <bertrand.marquis@arm.com>

diff --git a/xen/arch/arm/domain.c b/xen/arch/arm/domain.c
index 2f8eaab7b56b17dfa1e07376f63d42c65384c487..2cd481979cf11bab8640395c1d01e49270e2d2d3 100644 (file)
--- a/xen/arch/arm/domain.c
+++ b/xen/arch/arm/domain.c
@@ -63,7 +63,7 @@ static void do_idle(void)
     rcu_idle_exit(cpu);
 }
 
-void idle_loop(void)
+static void noreturn idle_loop(void)
 {
     unsigned int cpu = smp_processor_id();
 
@@ -331,6 +331,9 @@ static void schedule_tail(struct vcpu *prev)
     update_vcpu_system_time(current);
 }
 
+extern void noreturn return_to_new_vcpu32(void);
+extern void noreturn return_to_new_vcpu64(void);
+
 static void continue_new_vcpu(struct vcpu *prev)
 {
     current->arch.actlr = READ_SYSREG(ACTLR_EL1);

diff --git a/xen/arch/arm/include/asm/current.h b/xen/arch/arm/include/asm/current.h
index 73e81458e54a9da78d37d92680b80c7221866d86..6973eeb1d13ffa7f73868a7ed4b8b3382ed1b2f9 100644 (file)
--- a/xen/arch/arm/include/asm/current.h
+++ b/xen/arch/arm/include/asm/current.h
@@ -45,7 +45,7 @@ static inline struct cpu_info *get_cpu_info(void)
 #define guest_cpu_user_regs() (&get_cpu_info()->guest_cpu_user_regs)
 
 #define switch_stack_and_jump(stack, fn) do {                           \
-    asm volatile ("mov sp,%0; b " STR(fn) : : "r" (stack) : "memory" ); \
+    asm volatile ("mov sp,%0; b " STR(fn) : : "r" (stack), "X" (fn) : "memory" ); \
     unreachable();                                                      \
 } while ( false )