Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752991AbcDVJwZ (ORCPT ); Fri, 22 Apr 2016 05:52:25 -0400 Received: from terminus.zytor.com ([198.137.202.10]:37224 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751647AbcDVJwX (ORCPT ); Fri, 22 Apr 2016 05:52:23 -0400 Date: Fri, 22 Apr 2016 02:51:06 -0700 From: "tip-bot for Luis R. Rodriguez" Message-ID: Cc: dvlasenk@redhat.com, bp@alien8.de, peterz@infradead.org, hpa@zytor.com, brgerst@gmail.com, mcgrof@kernel.org, torvalds@linux-foundation.org, tglx@linutronix.de, mingo@kernel.org, linux-kernel@vger.kernel.org, luto@amacapital.net Reply-To: torvalds@linux-foundation.org, mcgrof@kernel.org, brgerst@gmail.com, mingo@kernel.org, tglx@linutronix.de, linux-kernel@vger.kernel.org, luto@amacapital.net, dvlasenk@redhat.com, peterz@infradead.org, hpa@zytor.com, bp@alien8.de In-Reply-To: <1460592286-300-7-git-send-email-mcgrof@kernel.org> References: <1460592286-300-7-git-send-email-mcgrof@kernel.org> To: linux-tip-commits@vger.kernel.org Subject: [tip:x86/boot] x86/init: Use a platform legacy quirk for EBDA Git-Commit-ID: 1330e3bc544a1951d81b7f3c7d4cecf77d906f67 X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3567 Lines: 113 Commit-ID: 1330e3bc544a1951d81b7f3c7d4cecf77d906f67 Gitweb: http://git.kernel.org/tip/1330e3bc544a1951d81b7f3c7d4cecf77d906f67 Author: Luis R. Rodriguez AuthorDate: Wed, 13 Apr 2016 17:04:36 -0700 Committer: Ingo Molnar CommitDate: Fri, 22 Apr 2016 10:29:02 +0200 x86/init: Use a platform legacy quirk for EBDA This replaces the paravirt_enabled() check with a proper x86 legacy platform quirk. As per 0-day, this bumps the vmlinux size using i386-tinyconfig as follows: TOTAL TEXT init.text x86_early_init_platform_quirks() +39 +35 +35 +25 That's a 4 byte total overhead, the rest is all cleared out upon init as its all __init text. v2: document 0-day vmlinux size impact Signed-off-by: Luis R. Rodriguez Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Brian Gerst Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: andrew.cooper3@citrix.com Cc: andriy.shevchenko@linux.intel.com Cc: bigeasy@linutronix.de Cc: boris.ostrovsky@oracle.com Cc: david.vrabel@citrix.com Cc: ffainelli@freebox.fr Cc: george.dunlap@citrix.com Cc: glin@suse.com Cc: jgross@suse.com Cc: jlee@suse.com Cc: josh@joshtriplett.org Cc: julien.grall@linaro.org Cc: konrad.wilk@oracle.com Cc: kozerkov@parallels.com Cc: lenb@kernel.org Cc: lguest@lists.ozlabs.org Cc: linux-acpi@vger.kernel.org Cc: lv.zheng@intel.com Cc: matt@codeblueprint.co.uk Cc: mbizon@freebox.fr Cc: rjw@rjwysocki.net Cc: robert.moore@intel.com Cc: rusty@rustcorp.com.au Cc: tiwai@suse.de Cc: toshi.kani@hp.com Cc: xen-devel@lists.xensource.com Link: http://lkml.kernel.org/r/1460592286-300-7-git-send-email-mcgrof@kernel.org Signed-off-by: Ingo Molnar --- arch/x86/include/asm/x86_init.h | 3 +++ arch/x86/kernel/head.c | 2 +- arch/x86/kernel/platform-quirks.c | 4 ++++ 3 files changed, 8 insertions(+), 1 deletion(-) diff --git a/arch/x86/include/asm/x86_init.h b/arch/x86/include/asm/x86_init.h index 8bb8c1a..89d9d57 100644 --- a/arch/x86/include/asm/x86_init.h +++ b/arch/x86/include/asm/x86_init.h @@ -145,9 +145,12 @@ struct timespec; * struct x86_legacy_features - legacy x86 features * * @rtc: this device has a CMOS real-time clock present + * @ebda_search: it's safe to search for the EBDA signature in the hardware's + * low RAM */ struct x86_legacy_features { int rtc; + int ebda_search; }; /** diff --git a/arch/x86/kernel/head.c b/arch/x86/kernel/head.c index 992f442..afe65df 100644 --- a/arch/x86/kernel/head.c +++ b/arch/x86/kernel/head.c @@ -38,7 +38,7 @@ void __init reserve_ebda_region(void) * that the paravirt case can handle memory setup * correctly, without our help. */ - if (paravirt_enabled()) + if (!x86_platform.legacy.ebda_search) return; /* end of low (conventional) memory */ diff --git a/arch/x86/kernel/platform-quirks.c b/arch/x86/kernel/platform-quirks.c index 021a5f9..01b1597 100644 --- a/arch/x86/kernel/platform-quirks.c +++ b/arch/x86/kernel/platform-quirks.c @@ -7,8 +7,12 @@ void __init x86_early_init_platform_quirks(void) { x86_platform.legacy.rtc = 1; + x86_platform.legacy.ebda_search = 0; switch (boot_params.hdr.hardware_subarch) { + case X86_SUBARCH_PC: + x86_platform.legacy.ebda_search = 1; + break; case X86_SUBARCH_XEN: case X86_SUBARCH_LGUEST: case X86_SUBARCH_INTEL_MID: