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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8DFF7C4332F for ; Mon, 25 Oct 2021 19:34:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7C3EF610C9 for ; Mon, 25 Oct 2021 19:34:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235661AbhJYThR (ORCPT ); Mon, 25 Oct 2021 15:37:17 -0400 Received: from mail.kernel.org ([198.145.29.99]:52126 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236274AbhJYTeE (ORCPT ); Mon, 25 Oct 2021 15:34:04 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id EC06360FE8; Mon, 25 Oct 2021 19:29:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1635190195; bh=n1tTSWQDnZCGccnS6zBfI+YWb3yAxp76XfmkA1dlrOQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=DtqtdV4+4cZVayHy7dSUDko9f67zYni1Apy3fVsx1FUoElEfsrlZTRxfy7/ZxStjl Y2d2OrXHio6NIpfkngdUYdT7RLLEs/VlvfQIc5cAX2uNm7ff/YmCAoJB7Po7/X5Lyw D4eWi1R0n6LkoEjpgP0kpj7OBr3cCXtKF+qEIz1k= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Jan Beulich , Juergen Gross , Sasha Levin Subject: [PATCH 5.10 07/95] xen/x86: prevent PVH type from getting clobbered Date: Mon, 25 Oct 2021 21:14:04 +0200 Message-Id: <20211025190957.449773881@linuxfoundation.org> X-Mailer: git-send-email 2.33.1 In-Reply-To: <20211025190956.374447057@linuxfoundation.org> References: <20211025190956.374447057@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: Jan Beulich [ Upstream commit 9172b5c4a778da1f855b2e3780b1afabb3cfd523 ] Like xen_start_flags, xen_domain_type gets set before .bss gets cleared. Hence this variable also needs to be prevented from getting put in .bss, which is possible because XEN_NATIVE is an enumerator evaluating to zero. Any use prior to init_hvm_pv_info() setting the variable again would lead to wrong decisions; one such case is xenboot_console_setup() when called as a result of "earlyprintk=xen". Use __ro_after_init as more applicable than either __section(".data") or __read_mostly. Signed-off-by: Jan Beulich Reviewed-by: Juergen Gross Link: https://lore.kernel.org/r/d301677b-6f22-5ae6-bd36-458e1f323d0b@suse.com Signed-off-by: Juergen Gross Signed-off-by: Sasha Levin --- arch/x86/xen/enlighten.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c index aa9f50fccc5d..0f68c6da7382 100644 --- a/arch/x86/xen/enlighten.c +++ b/arch/x86/xen/enlighten.c @@ -51,9 +51,6 @@ DEFINE_PER_CPU(struct vcpu_info, xen_vcpu_info); DEFINE_PER_CPU(uint32_t, xen_vcpu_id); EXPORT_PER_CPU_SYMBOL(xen_vcpu_id); -enum xen_domain_type xen_domain_type = XEN_NATIVE; -EXPORT_SYMBOL_GPL(xen_domain_type); - unsigned long *machine_to_phys_mapping = (void *)MACH2PHYS_VIRT_START; EXPORT_SYMBOL(machine_to_phys_mapping); unsigned long machine_to_phys_nr; @@ -68,9 +65,11 @@ __read_mostly int xen_have_vector_callback; EXPORT_SYMBOL_GPL(xen_have_vector_callback); /* - * NB: needs to live in .data because it's used by xen_prepare_pvh which runs - * before clearing the bss. + * NB: These need to live in .data or alike because they're used by + * xen_prepare_pvh() which runs before clearing the bss. */ +enum xen_domain_type __ro_after_init xen_domain_type = XEN_NATIVE; +EXPORT_SYMBOL_GPL(xen_domain_type); uint32_t xen_start_flags __section(".data") = 0; EXPORT_SYMBOL(xen_start_flags); -- 2.33.0