Commit ce0a1b60 authored by Arnd Bergmann's avatar Arnd Bergmann Committed by Borislav Petkov (AMD)
Browse files

x86/paravirt: Silence unused native_pv_lock_init() function warning 



The native_pv_lock_init() function is only used in SMP configurations
and declared in asm/qspinlock.h which is not used in UP kernels, but
the function is still defined for both, which causes a warning:

  arch/x86/kernel/paravirt.c:76:13: error: no previous prototype for 'native_pv_lock_init' [-Werror=missing-prototypes]

Move the declaration to asm/paravirt.h so it is visible even
with CONFIG_SMP but short-circuit the definition to turn it
into an empty function.

Signed-off-by: default avatarArnd Bergmann <arnd@arndb.de>
Signed-off-by: default avatarBorislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20230803082619.1369127-7-arnd@kernel.org
parent 1a3e4b4d

arch/x86/include/asm/paravirt.h

+7 −0
Original line number Diff line number Diff line
@@ -739,6 +739,7 @@ static __always_inline unsigned long arch_local_irq_save(void) 
	     ".popsection")



extern void default_banner(void);

void native_pv_lock_init(void) __init;



#else  /* __ASSEMBLY__ */
@@ -778,6 +779,12 @@ extern void default_banner(void); 
#endif /* __ASSEMBLY__ */

#else  /* CONFIG_PARAVIRT */

# define default_banner x86_init_noop



#ifndef __ASSEMBLY__

static inline void native_pv_lock_init(void)

{

}

#endif

#endif /* !CONFIG_PARAVIRT */



#ifndef __ASSEMBLY__

arch/x86/include/asm/qspinlock.h

+1 −6
Original line number Diff line number Diff line
@@ -74,8 +74,6 @@ static inline bool vcpu_is_preempted(long cpu) 
 */

DECLARE_STATIC_KEY_TRUE(virt_spin_lock_key);



void native_pv_lock_init(void) __init;



/*

 * Shortcut for the queued_spin_lock_slowpath() function that allows

 * virt to hijack it.
@@ -103,10 +101,7 @@ static inline bool virt_spin_lock(struct qspinlock *lock) 


	return true;

}

#else

static inline void native_pv_lock_init(void)

{

}



#endif /* CONFIG_PARAVIRT */



#include <asm-generic/qspinlock.h>

arch/x86/kernel/paravirt.c

+2 −1
Original line number Diff line number Diff line
@@ -75,7 +75,8 @@ DEFINE_STATIC_KEY_TRUE(virt_spin_lock_key); 


void __init native_pv_lock_init(void)

{

	if (!boot_cpu_has(X86_FEATURE_HYPERVISOR))

	if (IS_ENABLED(CONFIG_PARAVIRT_SPINLOCKS) &&

	    !boot_cpu_has(X86_FEATURE_HYPERVISOR))

		static_branch_disable(&virt_spin_lock_key);

}