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From: Vivek Goyal <vgoyal@in.ibm.com>
To: Andi Kleen <ak@suse.de>
Cc: linux kernel mailing list <linux-kernel@vger.kernel.org>,
	Reloc Kernel List <fastboot@lists.osdl.org>,
	ebiederm@xmission.com, akpm@osdl.org, hpa@zytor.com,
	magnus.damm@gmail.com, lwang@redhat.com, dzickus@redhat.com,
	pavel@suse.cz, "Rafael J. Wysocki" <rjw@sisk.pl>
Subject: Re: [RFC] [PATCH 10/16] x86_64: 64bit PIC ACPI wakeup
Date: Mon, 13 Nov 2006 12:59:47 -0500	[thread overview]
Message-ID: <20061113175947.GA13832@in.ibm.com> (raw)
In-Reply-To: <200611131822.44034.ak@suse.de>

On Mon, Nov 13, 2006 at 06:22:43PM +0100, Andi Kleen wrote:
[..]
> 
> > +verify_cpu:
> > +	pushl	$0			# Kill any dangerous flags
> > +	popfl
> > +
> > +	/* minimum CPUID flags for x86-64 */
> > +	/* see http://www.x86-64.org/lists/discuss/msg02971.html */
> > +#define REQUIRED_MASK1 ((1<<0)|(1<<3)|(1<<4)|(1<<5)|(1<<6)|(1<<8)|\
> > +			   (1<<13)|(1<<15)|(1<<24)|(1<<25)|(1<<26))
> > +#define REQUIRED_MASK2 (1<<29)
> 
> It would be much better if this least this CPUID code was in a common shared 
> file with head.S

Hi Andi,

This code (verify_cpu) is called while we are still in real mode. So it has
to be present in low 1MB. Now in trampoline has been designed to switch to
64bit mode and then jump to the kernel hence kernel can be loaded anywhere
even beyond (4G). So if we move this code into say arch/x86_64/kernel/head.S
then we can't even call it.

So I think we got to leave it in trampoline only.

Thanks
Vivek

  reply	other threads:[~2006-11-13 18:00 UTC|newest]

Thread overview: 51+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2006-11-13 16:21 [RFC] [PATCH 0/16] x86_64: Relocatable bzImage Support (V2) Vivek Goyal
2006-11-13 16:26 ` [RFC] [PATCH 1/16] x86_64: Align data segment to page size boundary Vivek Goyal
2006-11-13 16:28 ` [RFC] [PATCH 2/16] x86_64: Assembly safe page.h and pgtable.h Vivek Goyal
2006-11-13 17:17   ` Andi Kleen
2006-11-13 19:27     ` Eric W. Biederman
2006-11-13 21:16     ` Vivek Goyal
2006-11-14  1:46       ` Andi Kleen
2006-11-14  2:41         ` Eric W. Biederman
2006-11-13 16:30 ` [RFC] [PATCH 3/16] x86_64: Kill temp_boot_pmds Vivek Goyal
2006-11-13 16:31 ` [RFC] [PATCH 4/16] x86_64: Clean up the early boot page table Vivek Goyal
2006-11-13 16:33 ` [RFC] [PATCH 5/16] x86_64: Fix earlyprintk to use standard ISA mapping Vivek Goyal
2006-11-13 16:34 ` [RFC] [PATCH 6/16] x86_64: Modify copy_bootdata to to use virtual address Vivek Goyal
2006-11-13 16:35 ` [RFC] [PATCH 7/16] x86_64: cleanup segments Vivek Goyal
2006-11-13 16:40 ` [RFC] [PATCH 8/16] x86_64: Add EFER to the set registers saved by save_processor_state Vivek Goyal
2006-11-13 16:42 ` [RFC] [PATCH 9/16] x86_64: 64bit PIC SMP trampoline Vivek Goyal
2006-11-13 17:28   ` Andi Kleen
2006-11-13 16:43 ` [RFC] [PATCH 10/16] x86_64: 64bit PIC ACPI wakeup Vivek Goyal
2006-11-13 17:22   ` Andi Kleen
2006-11-13 17:59     ` Vivek Goyal [this message]
2006-11-13 18:13       ` Andi Kleen
2006-11-13 19:21         ` Eric W. Biederman
2006-11-13 19:34           ` Vivek Goyal
2006-11-13 19:57             ` Eric W. Biederman
2006-11-13 23:01     ` Pavel Machek
2006-11-13 23:09       ` Vivek Goyal
2006-11-15 21:07     ` [PATCH] x86_64: Move cpu long mode verification code to common file (was Re: [RFC] [PATCH 10/16] x86_64: 64bit PIC ACPI wakeup) Vivek Goyal
2006-11-15 22:54       ` Pavel Machek
2006-11-16 20:06         ` Vivek Goyal
2006-11-14 16:30   ` [RFC] [PATCH 10/16] x86_64: 64bit PIC ACPI wakeup Pavel Machek
2006-11-14 21:36     ` Eric W. Biederman
2006-11-14 21:40       ` H. Peter Anvin
2006-11-14 23:43       ` Pavel Machek
2006-11-15  3:49         ` Andi Kleen
2006-11-15 17:26         ` Eric W. Biederman
2006-11-15 18:29           ` Vivek Goyal
2006-11-15 18:38           ` Pavel Machek
2006-11-14 23:17     ` Vivek Goyal
2006-11-14 23:39       ` Pavel Machek
2006-11-15 21:24   ` [Fastboot] " Vivek Goyal
2006-11-15 23:03     ` Pavel Machek
2006-11-16  0:28     ` Vivek Goyal
2006-11-16 20:09       ` Vivek Goyal
2006-11-16 20:53         ` Pavel Machek
2006-11-16 21:29           ` Vivek Goyal
2006-11-16 21:51             ` Pavel Machek
2006-11-13 16:44 ` [RFC] [PATCH 11/16] x86_64: Modify discover_ebda to use virtual address Vivek Goyal
2006-11-13 16:46 ` [RFC] [PATCH 12/16] x86_64: Remove the identity mapping as early as possible Vivek Goyal
2006-11-13 16:47 ` [RFC] [PATCH 13/16] x86_64: __pa and __pa_symbol address space separation Vivek Goyal
2006-11-13 16:48 ` [RFC] [PATCH 14/16] x86_64: Remove CONFIG_PHYSICAL_START Vivek Goyal
2006-11-13 16:50 ` [RFC] [PATCH 15/16] x86_64: Relocatable kernel support Vivek Goyal
2006-11-13 16:51 ` [RFC] [PATCH 16/16] x86_64: Extend bzImage protocol for relocatable bzImage Vivek Goyal

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