Commit 2d2ccf24 authored by Thomas Gleixner's avatar Thomas Gleixner
Browse files

x86/Hyper-V/hv_apic: Build the Hyper-V APIC conditionally 



The Hyper-V APIC code is built when CONFIG_HYPERV is enabled but the actual
code in that file is guarded with CONFIG_X86_64. There is no point in doing
this. Neither is there a point in having the CONFIG_HYPERV guard in there
because the containing directory is not built when CONFIG_HYPERV=n.

Further for the hv_init_apic() function a stub is provided only for
CONFIG_HYPERV=n, which is pointless as the callsite is not compiled at
all. But for X86_32 the stub is missing and the build fails.

Clean that up:

  - Compile hv_apic.c only when CONFIG_X86_64=y
  - Make the stub for hv_init_apic() available when CONFG_X86_64=n

Fixes: 6b48cb5f ("X86/Hyper-V: Enlighten APIC access")
Reported-by: default avatarkbuild test robot <lkp@intel.com>
Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Cc: K. Y. Srinivasan <kys@microsoft.com>
Cc: Michael Kelley <mikelley@microsoft.com>
parent 61eeb1f6

arch/x86/hyperv/Makefile

+2 −1
Original line number Diff line number Diff line 
obj-y		:= hv_init.o mmu.o hv_apic.o
 
obj-y			:= hv_init.o mmu.o

obj-$(CONFIG_X86_64)	+= hv_apic.o

arch/x86/hyperv/hv_apic.c

+0 −6
Original line number Diff line number Diff line
@@ -31,9 +31,6 @@ 
#include <asm/mshyperv.h>

#include <asm/apic.h>



#ifdef CONFIG_X86_64

#if IS_ENABLED(CONFIG_HYPERV)



static struct apic orig_apic;



static u64 hv_apic_icr_read(void)
@@ -257,6 +254,3 @@ void __init hv_apic_init(void) 
		apic->icr_read  = hv_apic_icr_read;

	}

}
 


#endif /* CONFIG_HYPERV */

#endif /* CONFIG_X86_64 */

arch/x86/include/asm/mshyperv.h

+6 −1
Original line number Diff line number Diff line
@@ -302,7 +302,13 @@ void hyperv_reenlightenment_intr(struct pt_regs *regs); 
void set_hv_tscchange_cb(void (*cb)(void));

void clear_hv_tscchange_cb(void);

void hyperv_stop_tsc_emulation(void);



#ifdef CONFIG_X86_64

void hv_apic_init(void);

#else

static inline void hv_apic_init(void) {}

#endif



#else /* CONFIG_HYPERV */

static inline void hyperv_init(void) {}

static inline bool hv_is_hyperv_initialized(void) { return false; }
@@ -311,7 +317,6 @@ static inline void hyperv_setup_mmu_ops(void) {} 
static inline void set_hv_tscchange_cb(void (*cb)(void)) {}

static inline void clear_hv_tscchange_cb(void) {}

static inline void hyperv_stop_tsc_emulation(void) {};

static inline void hv_apic_init(void) {}

static inline struct hv_vp_assist_page *hv_get_vp_assist_page(unsigned int cpu)

{

	return NULL;

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