Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 8fd3f98d authored by Nicholas Piggin's avatar Nicholas Piggin Committed by Greg Kroah-Hartman
Browse files

powerpc/64: Add macros for annotating the destination of rfid/hrfid 



commit 50e51c13b3822d14ff6df4279423e4b7b2269bc3 upstream.

The rfid/hrfid ((Hypervisor) Return From Interrupt) instruction is
used for switching from the kernel to userspace, and from the
hypervisor to the guest kernel. However it can and is also used for
other transitions, eg. from real mode kernel code to virtual mode
kernel code, and it's not always clear from the code what the
destination context is.

To make it clearer when reading the code, add macros which encode the
expected destination context.

Signed-off-by: default avatarNicholas Piggin <npiggin@gmail.com>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent be6641a7

arch/powerpc/include/asm/exception-64e.h

+6 −0
Original line number Diff line number Diff line
@@ -209,5 +209,11 @@ exc_##label##_book3e: 
	ori	r3,r3,vector_offset@l;		\

	mtspr	SPRN_IVOR##vector_number,r3;



#define RFI_TO_KERNEL							\

	rfi



#define RFI_TO_USER							\

	rfi



#endif /* _ASM_POWERPC_EXCEPTION_64E_H */

arch/powerpc/include/asm/exception-64s.h

+29 −0
Original line number Diff line number Diff line
@@ -51,6 +51,35 @@ 
#define EX_PPR		88	/* SMT thread status register (priority) */

#define EX_CTR		96



/* Macros for annotating the expected destination of (h)rfid */



#define RFI_TO_KERNEL							\

	rfid



#define RFI_TO_USER							\

	rfid



#define RFI_TO_USER_OR_KERNEL						\

	rfid



#define RFI_TO_GUEST							\

	rfid



#define HRFI_TO_KERNEL							\

	hrfid



#define HRFI_TO_USER							\

	hrfid



#define HRFI_TO_USER_OR_KERNEL						\

	hrfid



#define HRFI_TO_GUEST							\

	hrfid



#define HRFI_TO_UNKNOWN							\

	hrfid



#ifdef CONFIG_RELOCATABLE

#define __EXCEPTION_RELON_PROLOG_PSERIES_1(label, h)			\

	mfspr	r11,SPRN_##h##SRR0;	/* save SRR0 */			\