Commit 6da5175d authored by Kirill A. Shutemov's avatar Kirill A. Shutemov Committed by Dave Hansen
Browse files

x86/paravirt: Fix build PARAVIRT_XXL=y without XEN_PV 



Kernel fails to compile with PARAVIRT_XXL=y if XEN_PV is not enabled:

	ld.lld: error: undefined symbol: xen_iret

It happens because INTERRUPT_RETURN defined to use xen_iret if
CONFIG_PARAVIRT_XXL enabled regardless of CONFIG_XEN_PV.

The issue is not visible in the current kernel because CONFIG_XEN_PV is
the only user of CONFIG_PARAVIRT_XXL and there's no way to enable them
separately.

Rework code to define INTERRUPT_RETURN based on CONFIG_XEN_PV, not
CONFIG_PARAVIRT_XXL.

Signed-off-by: default avatarKirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: default avatarDave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: default avatarJuergen Gross <jgross@suse.com>
Link: https://lkml.kernel.org/r/20211130185533.32658-1-kirill.shutemov@linux.intel.com
parent d58071a8

arch/x86/include/asm/irqflags.h

+5 −2
Original line number Diff line number Diff line
@@ -114,8 +114,6 @@ static __always_inline unsigned long arch_local_irq_save(void) 
#define SAVE_FLAGS		pushfq; popq %rax

#endif



#define INTERRUPT_RETURN	jmp native_iret



#endif



#endif /* __ASSEMBLY__ */
@@ -143,8 +141,13 @@ static __always_inline void arch_local_irq_restore(unsigned long flags) 
#ifdef CONFIG_X86_64

#ifdef CONFIG_XEN_PV

#define SWAPGS	ALTERNATIVE "swapgs", "", X86_FEATURE_XENPV

#define INTERRUPT_RETURN						\

	ANNOTATE_RETPOLINE_SAFE;					\

	ALTERNATIVE_TERNARY("jmp *paravirt_iret(%rip);",		\

		X86_FEATURE_XENPV, "jmp xen_iret;", "jmp native_iret;")

#else

#define SWAPGS	swapgs

#define INTERRUPT_RETURN	jmp native_iret

#endif

#endif

#endif /* !__ASSEMBLY__ */

arch/x86/include/asm/paravirt.h

+0 −5
Original line number Diff line number Diff line
@@ -752,11 +752,6 @@ extern void default_banner(void); 
#define PARA_SITE(ptype, ops)	_PVSITE(ptype, ops, .quad, 8)

#define PARA_INDIRECT(addr)	*addr(%rip)



#define INTERRUPT_RETURN						\

	ANNOTATE_RETPOLINE_SAFE;					\

	ALTERNATIVE_TERNARY("jmp *paravirt_iret(%rip);",		\

		X86_FEATURE_XENPV, "jmp xen_iret;", "jmp native_iret;")



#ifdef CONFIG_DEBUG_ENTRY

.macro PARA_IRQ_save_fl

	PARA_SITE(PARA_PATCH(PV_IRQ_save_fl),