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 X-Spam-Level: X-Spam-Status: No, score=-17.0 required=3.0 tests=BAYES_00,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2F527C4338F for ; Thu, 12 Aug 2021 19:02:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 00963610A3 for ; Thu, 12 Aug 2021 19:02:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235145AbhHLTDC (ORCPT ); Thu, 12 Aug 2021 15:03:02 -0400 Received: from mail.kernel.org ([198.145.29.99]:59300 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234899AbhHLTC7 (ORCPT ); Thu, 12 Aug 2021 15:02:59 -0400 Received: from disco-boy.misterjones.org (disco-boy.misterjones.org [51.254.78.96]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 37728610CC; Thu, 12 Aug 2021 19:02:34 +0000 (UTC) Received: from sofa.misterjones.org ([185.219.108.64] helo=why.lan) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1mEFyK-004c9r-JU; Thu, 12 Aug 2021 20:02:32 +0100 From: Marc Zyngier To: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Cc: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= , Will Deacon , Catalin Marinas , Mark Rutland , Ard Biesheuvel , Florian Fainelli , bcm-kernel-feedback-list@broadcom.com, kernel-team@android.com Subject: [PATCH 2/5] arm64: Handle UNDEF in the EL2 stub vectors Date: Thu, 12 Aug 2021 20:02:10 +0100 Message-Id: <20210812190213.2601506-3-maz@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210812190213.2601506-1-maz@kernel.org> References: <20210812190213.2601506-1-maz@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, zajec5@gmail.com, will@kernel.org, catalin.marinas@arm.com, mark.rutland@arm.com, ardb@kernel.org, f.fainelli@gmail.com, bcm-kernel-feedback-list@broadcom.com, kernel-team@android.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org As we want to handle the silly case where HVC has been disabled from EL3, augment our ability to handle exception at EL2. Check for unknown exceptions (usually UNDEF) coming from EL2, and treat them as a failing HVC call into the stubs. While this isn't great and obviously doesn't catter for the gigantic range of possible exceptions, it isn't any worse than what we have today. Just don't try and use it for anything else. Signed-off-by: Marc Zyngier --- arch/arm64/kernel/hyp-stub.S | 19 ++++++++++++++++++- 1 file changed, 18 insertions(+), 1 deletion(-) diff --git a/arch/arm64/kernel/hyp-stub.S b/arch/arm64/kernel/hyp-stub.S index 43d212618834..026a34515b21 100644 --- a/arch/arm64/kernel/hyp-stub.S +++ b/arch/arm64/kernel/hyp-stub.S @@ -46,7 +46,16 @@ SYM_CODE_END(__hyp_stub_vectors) .align 11 SYM_CODE_START_LOCAL(elx_sync) - cmp x0, #HVC_SET_VECTORS + mrs x4, spsr_el2 + and x4, x4, #PSR_MODE_MASK + orr x4, x4, #1 + cmp x4, #PSR_MODE_EL2h + b.ne 0f + mrs x4, esr_el2 + eor x4, x4, #ESR_ELx_IL + cbz x4, el2_undef + +0: cmp x0, #HVC_SET_VECTORS b.ne 1f msr vbar_el2, x1 b 9f @@ -71,6 +80,14 @@ SYM_CODE_START_LOCAL(elx_sync) 9: mov x0, xzr eret + +el2_undef: + // Assumes this was a HVC that went really wrong... + mrs x0, elr_el2 + add x0, x0, #4 + msr elr_el2, x0 + mov_q x0, HVC_STUB_ERR + eret SYM_CODE_END(elx_sync) // nVHE? No way! Give me the real thing! -- 2.30.2