Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752634Ab0LWJ6t (ORCPT ); Thu, 23 Dec 2010 04:58:49 -0500 Received: from smtp4-g21.free.fr ([212.27.42.4]:46300 "EHLO smtp4-g21.free.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752103Ab0LWJ6r (ORCPT ); Thu, 23 Dec 2010 04:58:47 -0500 From: Florian Fainelli To: linux-kernel@vger.kernel.org Subject: Re: [PATCH] x86/trampoline: fallback to fixed trampoline address if no e820 map is provided Date: Thu, 23 Dec 2010 10:57:34 +0100 User-Agent: KMail/1.13.5 (Linux/2.6.35-23-server; KDE/4.5.1; x86_64; ; ) Cc: Dirk Brandewie , sodaville@linutronix.de, Ingo Molnar , Yinghai Lu References: <201012142219.40062.ffainelli@freebox.fr> In-Reply-To: <201012142219.40062.ffainelli@freebox.fr> Organization: Freebox MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Message-Id: <201012231057.35021.ffainelli@freebox.fr> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2203 Lines: 53 On Tuesday 14 December 2010 22:19:39 Florian Fainelli wrote: > From: Florian Fainelli > > Since 893f38d1 (x86: Use find_e820() instead of hard coded trampoline > address), the trampoline base address should be provided by the BIOS as an > e820 area. Some minimalistic BIOSes (like CEFDK on CE4100) may not provide > any e820 area, still we should fallback to a fixed trampoline base address > for SMP to work correctly. > > Cc: Dirk Brandewie > Cc: sodaville@linutronix.de > Cc: Ingo Molnar > Cc: Yinghai Lu > Signed-off-by: Florian Fainelli Ingo, Yinghai, anything wrong with that patch? Thank you. > --- > diff --git a/arch/x86/include/asm/trampoline.h > b/arch/x86/include/asm/trampoline.h index f4500fb..908b395 100644 > --- a/arch/x86/include/asm/trampoline.h > +++ b/arch/x86/include/asm/trampoline.h > @@ -16,6 +16,7 @@ extern unsigned long initial_code; > extern unsigned long initial_gs; > > #define TRAMPOLINE_SIZE roundup(trampoline_end - trampoline_data, > PAGE_SIZE) +#define TRAMPOLINE_BASE 0x6000 > > extern unsigned long setup_trampoline(void); > extern void __init reserve_trampoline_memory(void); > diff --git a/arch/x86/kernel/trampoline.c b/arch/x86/kernel/trampoline.c > index f1488a3..d025aae 100644 > --- a/arch/x86/kernel/trampoline.c > +++ b/arch/x86/kernel/trampoline.c > @@ -21,8 +21,11 @@ void __init reserve_trampoline_memory(void) > > /* Has to be in very low memory so we can execute real-mode AP code. */ > mem = find_e820_area(0, 1<<20, TRAMPOLINE_SIZE, PAGE_SIZE); > - if (mem == -1L) > - panic("Cannot allocate trampoline\n"); > + if (mem == -1L) { > + printk(KERN_INFO "BIOS did not provide e820 area for trampoline" > + " ,using static trampoline address\n"); > + mem = TRAMPOLINE_BASE; > + } > > trampoline_base = __va(mem); > reserve_early(mem, mem + TRAMPOLINE_SIZE, "TRAMPOLINE"); -- 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/