From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754873AbdGURSl (ORCPT ); Fri, 21 Jul 2017 13:18:41 -0400 Received: from foss.arm.com ([217.140.101.70]:38944 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754740AbdGURPx (ORCPT ); Fri, 21 Jul 2017 13:15:53 -0400 From: Marc Zyngier To: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Cc: Mark Rutland , Russell King , Catalin Marinas , Will Deacon , Daniel Lezcano , Thomas Gleixner Subject: [PATCH 03/16] arm64: compat: Add separate CP15 trapping hook Date: Fri, 21 Jul 2017 18:15:29 +0100 Message-Id: <20170721171542.27639-4-marc.zyngier@arm.com> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20170721171542.27639-1-marc.zyngier@arm.com> References: <20170721171542.27639-1-marc.zyngier@arm.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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: Mark Rutland Signed-off-by: Marc Zyngier --- arch/arm64/kernel/entry.S | 14 ++++++++++++-- arch/arm64/kernel/traps.c | 13 +++++++++++++ 2 files changed, 25 insertions(+), 2 deletions(-) diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S index b738880350f9..d78fe4594338 100644 --- a/arch/arm64/kernel/entry.S +++ b/arch/arm64/kernel/entry.S @@ -560,9 +560,9 @@ 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 @@ -585,6 +585,16 @@ el0_svc_compat: el0_irq_compat: kernel_entry 0, 32 b el0_irq_naked +el0_cp15: + /* + * Trapped CP15 (MRC, MCR, MRRC, MCRR) instructions + */ + enable_dbg_and_irq + ct_user_exit + mov x0, x25 + mov x1, sp + bl do_cp15instr + b ret_to_user #endif el0_da: diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c index b02295673216..19e4f8d9a73c 100644 --- a/arch/arm64/kernel/traps.c +++ b/arch/arm64/kernel/traps.c @@ -556,6 +556,19 @@ 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; -- 2.11.0