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
Subject: Re: [PATCH v3 08/12] x86, boot: Don't check if cmd_line_ptr is accessible in misc/decompressor()
Date: Wed, 21 Nov 2012 09:21:09 -0800 [thread overview]
Message-ID: <50AD0D85.5070906@zytor.com> (raw)
In-Reply-To: <1353482170-10160-9-git-send-email-yinghai@kernel.org>
On 11/20/2012 11:16 PM, Yinghai Lu wrote:
> At that stage, it is already in 32bit protected mode or 64bit mode.
> so we do not need to check if ptr less 1M.
>
> When go from other boot loader (kexec) instead of boot/ code path.
>
> Move out accessible checking out __cmdline_find_option....
>
> So misc.c will parse cmdline and have debug print out.
Your description doesn't seem to match the code, and is incredibly
confusing to the reader.
The reason why is because you leave out an essential piece of
information: cmdline.c is included both in 16-bit code and in the
decompressor (32/64-bit code), so you want to move the test out of the
shared code.
-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:[~2012-11-21 17:21 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 [this message]
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
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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