From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753431AbaDDOMa (ORCPT ); Fri, 4 Apr 2014 10:12:30 -0400 Received: from mx1.redhat.com ([209.132.183.28]:31929 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753090AbaDDOM1 (ORCPT ); Fri, 4 Apr 2014 10:12:27 -0400 Date: Fri, 4 Apr 2014 10:12:18 -0400 From: Vivek Goyal To: "K. Y. Srinivasan" Cc: x86@kernel.org, linux-kernel@vger.kernel.org, olaf@aepfle.de, apw@canonical.com, jasowang@redhat.com, hpa@zytor.com, "K. Y. Srinivasan" , stable@vger.kernel.org Subject: Re: [PATCH 1/1] x86/platform/hyperv: When on Hyper-v use NULL legacy PIC Message-ID: <20140404141218.GA2161@redhat.com> References: <1396574193-12043-1-git-send-email-kys@microsoft.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1396574193-12043-1-git-send-email-kys@microsoft.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Apr 03, 2014 at 06:16:33PM -0700, K. Y. Srinivasan wrote: > Use the NULL legacy PIC when on Hyper-V. With this change we can support kexec > even when booting on EFI firmware. This patch has been tested on both EFI as > well as non-EFI firmware stacks on Hyper-V. > > This patch is required to support kexec on EFI firmware on Hyper-V. Please > apply. Can you give some more details about what's the problem we run into with kexec on EFI on hyper-V. Now EFI should be enabled in kexeced kernel. That means efi_enabled(EFI_BOOT) should be true and that means you would set legacy_pic to null anyway. So with this patch, what changed w.r.t kexec on EFI. Thansk Vivek > > Signed-off-by: K. Y. Srinivasan > Cc: [3.13+] > --- > arch/x86/kernel/cpu/mshyperv.c | 10 ++-------- > 1 files changed, 2 insertions(+), 8 deletions(-) > > diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c > index 76f98fe..47359f7 100644 > --- a/arch/x86/kernel/cpu/mshyperv.c > +++ b/arch/x86/kernel/cpu/mshyperv.c > @@ -133,14 +133,8 @@ static void __init ms_hyperv_init_platform(void) > printk(KERN_INFO "HyperV: LAPIC Timer Frequency: %#x\n", > lapic_timer_frequency); > > - /* > - * On Hyper-V, when we are booting off an EFI firmware stack, > - * we do not have many legacy devices including PIC, PIT etc. > - */ > - if (efi_enabled(EFI_BOOT)) { > - printk(KERN_INFO "HyperV: Using null_legacy_pic\n"); > - legacy_pic = &null_legacy_pic; > - } > + printk(KERN_INFO "HyperV: Using null_legacy_pic\n"); > + legacy_pic = &null_legacy_pic; > } > #endif > > -- > 1.7.4.1 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/