From: "H. Peter Anvin" <hpa@zytor.com>
To: Yinghai Lu <yinghai@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@elte.hu>,
"Eric W. Biederman" <ebiederm@xmission.com>,
linux-kernel@vger.kernel.org, Rob Landley <rob@landley.net>,
Matt Fleming <matt.fleming@intel.com>
Subject: Re: [PATCH v3 11/12] x86, boot: add fields to support load bzImage and ramdisk high
Date: Thu, 22 Nov 2012 10:37:27 -0800 [thread overview]
Message-ID: <50AE70E7.6060204@zytor.com> (raw)
In-Reply-To: <CAE9FiQUoj9k0Tbqp8LC8Wb21_s_x8naiWX4zkX9pJG-oFnAQ9g@mail.gmail.com>
On 11/22/2012 10:28 AM, Yinghai Lu wrote:
>
> has problem with old kexec, it only copy header from bzImage include
> setup_header as boot_param.
>
How old are we talking here? This is a clear and blatant bug, and it
would affect a whole bunch of things, not just this. In fact, one
really has to wonder how it can work at all.
One option I guess would be to have a sentinel field which, if it is not
zero, causes the kernel to zero all of struct setup_info outside of
setup_header... however, I have a nasty suspicion that this kexec botch
might be initializing some fields and leaving others unmodified, which
basically means "there is no hope for sanity and it is just working by
pure accident."
Eric, do you have any insight here?
> looks we only can use [0x30,0x3c), [0x1e8, 0x1f0), but in boot_params, they
> are apm_bios_info, and alt_mem_k...
... which I suspect get set by said kexec botch.
> so looks we still have to use setup_header instead.
We need to dig into this and either say "this is unsupportable" or put
in some kind of hack.
-hpa
--
H. Peter Anvin, Intel Open Source Technology Center
I work for Intel. I don't speak on their behalf.
next prev parent reply other threads:[~2012-11-22 22:22 UTC|newest]
Thread overview: 57+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-11-21 7:15 [PATCH v3 00/12] x86, boot, 64bit: Add support for loading ramdisk and bzImage high Yinghai Lu
2012-11-21 7:15 ` [PATCH v3 01/12] x86, boot: move verify_cpu.S after 0x200 Yinghai Lu
2012-11-21 17:23 ` H. Peter Anvin
2012-11-21 19:45 ` Yinghai Lu
2012-11-21 19:50 ` H. Peter Anvin
2012-11-21 20:15 ` Yinghai Lu
2012-11-22 5:48 ` Eric W. Biederman
[not found] ` <3178cb29-0e9e-44d2-b21f-45c53f38980a@email.android.com>
2012-11-22 11:27 ` Eric W. Biederman
2012-11-24 7:00 ` Yinghai Lu
2012-11-21 7:16 ` [PATCH v3 02/12] x86, boot: Move lldt/ltr out of 64bit code section Yinghai Lu
2012-11-21 7:16 ` [PATCH v3 03/12] x86, 64bit: set extra ident page table for whole kernel range Yinghai Lu
2012-11-21 7:16 ` [PATCH v3 04/12] x86, 64bit: add support for loading kernel above 512G Yinghai Lu
2012-11-21 7:16 ` [PATCH v3 05/12] x86: Merge early_reserve_initrd for 32bit and 64bit Yinghai Lu
2012-11-21 7:40 ` Pekka Enberg
2012-11-21 7:16 ` [PATCH v3 06/12] x86: add get_ramdisk_image/size Yinghai Lu
2012-11-21 7:16 ` [PATCH v3 07/12] x86, boot: add get_cmd_line_ptr() Yinghai Lu
2012-11-21 7:16 ` [PATCH v3 08/12] x86, boot: Don't check if cmd_line_ptr is accessible in misc/decompressor() Yinghai Lu
2012-11-21 17:21 ` H. Peter Anvin
2012-11-21 19:18 ` Yinghai Lu
2012-11-21 7:16 ` [PATCH v3 09/12] x86, boot: update cmd_line_ptr to unsigned long Yinghai Lu
2012-11-21 7:16 ` [PATCH v3 10/12] x86: use io_remap to access real_mode_data Yinghai Lu
2012-11-21 7:16 ` [PATCH v3 11/12] x86, boot: add fields to support load bzImage and ramdisk high Yinghai Lu
2012-11-21 17:17 ` H. Peter Anvin
2012-11-21 18:59 ` Yinghai Lu
2012-11-21 19:18 ` H. Peter Anvin
2012-11-22 5:56 ` Yinghai Lu
[not found] ` <a1ca794a-09d4-4d36-8c8c-67100cb3696e@email.android.com>
2012-11-22 6:47 ` Yinghai Lu
2012-11-22 6:58 ` Yinghai Lu
2012-11-22 15:59 ` H. Peter Anvin
2012-11-22 18:28 ` Yinghai Lu
2012-11-22 18:37 ` H. Peter Anvin [this message]
2012-11-22 18:50 ` Yinghai Lu
2012-11-22 18:51 ` H. Peter Anvin
2012-11-22 20:18 ` Yinghai Lu
2012-11-22 20:20 ` H. Peter Anvin
2012-11-22 20:29 ` Yinghai Lu
2012-11-22 20:50 ` H. Peter Anvin
2012-11-22 21:02 ` H. Peter Anvin
2012-11-22 22:13 ` Yinghai Lu
2012-11-24 12:37 ` Eric W. Biederman
2012-11-24 17:32 ` H. Peter Anvin
[not found] ` <CAE9FiQV0Q0fi7TrNjihdsUt0ueT4LLON4o+JEmX6ry9S6AU-ug@mail.gmail.com>
2012-11-24 18:24 ` H. Peter Anvin
2012-11-24 19:50 ` H. Peter Anvin
2012-11-24 21:30 ` Yinghai Lu
2012-11-24 21:38 ` H. Peter Anvin
2012-11-24 22:18 ` Yinghai Lu
2012-11-24 22:32 ` H. Peter Anvin
2012-11-24 23:24 ` Yinghai Lu
2012-11-24 23:50 ` Eric W. Biederman
2012-11-25 0:04 ` H. Peter Anvin
2012-11-25 0:11 ` Yinghai Lu
2012-11-25 5:50 ` Yinghai Lu
2012-11-25 5:52 ` H. Peter Anvin
2012-11-25 6:09 ` Yinghai Lu
2012-11-25 0:04 ` Yinghai Lu
2012-11-25 0:06 ` H. Peter Anvin
2012-11-21 7:16 ` [PATCH v3 12/12] x86: remove 1024g limitation for kexec buffer on 64bit Yinghai Lu
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