From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id EEA36C433EF for ; Fri, 1 Apr 2022 06:37:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S245580AbiDAGjX (ORCPT ); Fri, 1 Apr 2022 02:39:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46708 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S245578AbiDAGi4 (ORCPT ); Fri, 1 Apr 2022 02:38:56 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id ED7B91945E5; Thu, 31 Mar 2022 23:37:05 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 97299B82273; Fri, 1 Apr 2022 06:37:04 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0B8F9C2BBE4; Fri, 1 Apr 2022 06:37:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1648795023; bh=Pwi1NXMGMROD5CKak5cyf8+se5lmmjYhOio0Budtwjw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=y1iKse9A18ioRF1kh8951NsG/n4DDWyndoA8QAvyjvi2nUv/iEXNRRQ0ZSN34H7/1 7vepjBPBCzymq/ekfwgyWsRKnllrT5N5t9OVM+FSs5TbOnEhRhkmQgajCZZS+Ri1sy 4U2Gi+UvzUpWIqTefD8zk2iywAo4LGxaMwNk+UR4= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, "Russell King (Oracle)" , Catalin Marinas , James Morse Subject: [PATCH 4.14 16/27] arm64: entry: Make the kpti trampolines kpti sequence optional Date: Fri, 1 Apr 2022 08:36:26 +0200 Message-Id: <20220401063624.693165633@linuxfoundation.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220401063624.232282121@linuxfoundation.org> References: <20220401063624.232282121@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: James Morse commit c47e4d04ba0f1ea17353d85d45f611277507e07a upstream. Spectre-BHB needs to add sequences to the vectors. Having one global set of vectors is a problem for big/little systems where the sequence is costly on cpus that are not vulnerable. Making the vectors per-cpu in the style of KVM's bh_harden_hyp_vecs requires the vectors to be generated by macros. Make the kpti re-mapping of the kernel optional, so the macros can be used without kpti. Reviewed-by: Russell King (Oracle) Reviewed-by: Catalin Marinas Signed-off-by: James Morse Signed-off-by: Greg Kroah-Hartman --- arch/arm64/kernel/entry.S | 17 +++++++++++------ 1 file changed, 11 insertions(+), 6 deletions(-) --- a/arch/arm64/kernel/entry.S +++ b/arch/arm64/kernel/entry.S @@ -1022,9 +1022,10 @@ alternative_else_nop_endif sub \dst, \dst, PAGE_SIZE .endm - .macro tramp_ventry, vector_start, regsize + .macro tramp_ventry, vector_start, regsize, kpti .align 7 1: + .if \kpti == 1 .if \regsize == 64 msr tpidrro_el0, x30 // Restored in kernel_ventry .endif @@ -1046,8 +1047,12 @@ alternative_insn isb, nop, ARM64_WORKARO #endif prfm plil1strm, [x30, #(1b - \vector_start)] msr vbar_el1, x30 - add x30, x30, #(1b - \vector_start + 4) isb + .else + ldr x30, =vectors + .endif // \kpti == 1 + + add x30, x30, #(1b - \vector_start + 4) ret .org 1b + 128 // Did we overflow the ventry slot? .endm @@ -1064,15 +1069,15 @@ alternative_insn isb, nop, ARM64_WORKARO eret .endm - .macro generate_tramp_vector + .macro generate_tramp_vector, kpti .Lvector_start\@: .space 0x400 .rept 4 - tramp_ventry .Lvector_start\@, 64 + tramp_ventry .Lvector_start\@, 64, \kpti .endr .rept 4 - tramp_ventry .Lvector_start\@, 32 + tramp_ventry .Lvector_start\@, 32, \kpti .endr .endm @@ -1083,7 +1088,7 @@ alternative_insn isb, nop, ARM64_WORKARO .pushsection ".entry.tramp.text", "ax" .align 11 ENTRY(tramp_vectors) - generate_tramp_vector + generate_tramp_vector kpti=1 END(tramp_vectors) ENTRY(tramp_exit_native)