Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752452Ab0LWNRl (ORCPT ); Thu, 23 Dec 2010 08:17:41 -0500 Received: from rcsinet10.oracle.com ([148.87.113.121]:30420 "EHLO rcsinet10.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751493Ab0LWNRk (ORCPT ); Thu, 23 Dec 2010 08:17:40 -0500 References: <201012142219.40062.ffainelli@freebox.fr> <201012231057.35021.ffainelli@freebox.fr> In-Reply-To: <201012231057.35021.ffainelli@freebox.fr> Mime-Version: 1.0 (iPhone Mail 8C148) Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset=us-ascii Message-Id: <7A03AE18-9737-41D6-8EF5-6C6C29C1BF0D@kernel.org> Cc: "linux-kernel@vger.kernel.org" , Dirk Brandewie , "sodaville@linutronix.de" , Ingo Molnar X-Mailer: iPhone Mail (8C148) From: Yinghai Subject: Re: [PATCH] x86/trampoline: fallback to fixed trampoline address if no e820 map is provided Date: Thu, 23 Dec 2010 05:16:35 -0800 To: Florian Fainelli Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2533 Lines: 70 On Dec 23, 2010, at 1:57 AM, Florian Fainelli wrote: > 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. No e820 memmap ? Not sure how does it work Do you have boot log with debug ? Also recent kernel is using memblock already for finding free area. Thanks >> >> 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/