Commit 70c63cdf authored by Marc Zyngier's avatar Marc Zyngier Committed by Catalin Marinas
Browse files

arm64: compat: Add separate CP15 trapping hook 



Instead of directly generating an UNDEF when trapping a CP15 access,
let's add a new entry point to that effect (which only generates an
UNDEF for now).

Acked-by: default avatarMark Rutland <mark.rutland@arm.com>
Signed-off-by: default avatarMarc Zyngier <marc.zyngier@arm.com>
Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
parent bd7ac140

arch/arm64/kernel/entry.S

+13 −2
Original line number Diff line number Diff line
@@ -697,9 +697,9 @@ el0_sync_compat: 
	cmp	x24, #ESR_ELx_EC_UNKNOWN	// unknown exception in EL0

	b.eq	el0_undef

	cmp	x24, #ESR_ELx_EC_CP15_32	// CP15 MRC/MCR trap

	b.eq	el0_undef

	b.eq	el0_cp15

	cmp	x24, #ESR_ELx_EC_CP15_64	// CP15 MRRC/MCRR trap

	b.eq	el0_undef

	b.eq	el0_cp15

	cmp	x24, #ESR_ELx_EC_CP14_MR	// CP14 MRC/MCR trap

	b.eq	el0_undef

	cmp	x24, #ESR_ELx_EC_CP14_LS	// CP14 LDC/STC trap
@@ -722,6 +722,17 @@ el0_irq_compat: 
el0_error_compat:

	kernel_entry 0, 32

	b	el0_error_naked



el0_cp15:

	/*

	 * Trapped CP15 (MRC, MCR, MRRC, MCRR) instructions

	 */

	enable_daif

	ct_user_exit

	mov	x0, x25

	mov	x1, sp

	bl	do_cp15instr

	b	ret_to_user

#endif



el0_da:

arch/arm64/kernel/traps.c

+13 −0
Original line number Diff line number Diff line
@@ -547,6 +547,19 @@ static struct sys64_hook sys64_hooks[] = { 
	{},

};





#ifdef CONFIG_COMPAT

asmlinkage void __exception do_cp15instr(unsigned int esr, struct pt_regs *regs)

{

	/*

	 * New cp15 instructions may previously have been undefined at

	 * EL0. Fall back to our usual undefined instruction handler

	 * so that we handle these consistently.

	 */

	do_undefinstr(regs);

}

#endif



asmlinkage void __exception do_sysinstr(unsigned int esr, struct pt_regs *regs)

{

	struct sys64_hook *hook;

CRA Git | Maintained and supported by SUSTech CRA and CCSE