From: "H. Peter Anvin" <hpa@zytor.com>
To: "Eric W. Biederman" <ebiederm@xmission.com>, Tejun Heo <tj@kernel.org>
Cc: hacklu <embedway.linux@gmail.com>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 2/2] x86, boot: Optimize the elf header handling.
Date: Sun, 01 Jul 2012 11:37:22 -0700 [thread overview]
Message-ID: <4FF098E2.3040307@zytor.com> (raw)
In-Reply-To: <87a9zj9w43.fsf@xmission.com>
On 07/01/2012 11:25 AM, Eric W. Biederman wrote:
>
> Well I see what is going on now.
>
> In the vmlinux the paddrs and the poffsests stop tracking when they
> come to the percpu PT_LOAD segment.
>
> It looks like we give the percpu segment a 4K alignment in memory
> and a 2M alignment in the file.
>
> It looks like something is causing ld to compute an unfortunate physical
> load address for the percpu section.
>
> At first glace I would say that is a bug. Either we need the alignment
> or we don't. But if we need the alignment we certainly need it to
> be respected for the real memory locations of the init symbols..
>
If we don't need it, I think we can use -z max-page-size=4096, but we
use the PMD alignment for percpu on x86-64; Tejun, does that apply to
the .data..percpu section in the executable as well?
-hpa
next prev parent reply other threads:[~2012-07-01 18:37 UTC|newest]
Thread overview: 34+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-05-17 5:56 why the decompressed procedure move kernel from address 0x100000(1M) to 0x1000000(16M) +x hacklu
2012-06-02 23:48 ` Eric W. Biederman
2012-06-03 3:10 ` H. Peter Anvin
2012-06-03 8:41 ` Eric W. Biederman
2012-06-03 13:01 ` H. Peter Anvin
2012-06-03 20:30 ` [PATCH 1/2] x86, boot: Don't overlap the compressed and non-compressed image Eric W. Biederman
2012-06-03 20:32 ` [PATCH 2/2] x86, boot: Optimize the elf header handling Eric W. Biederman
2012-07-01 14:56 ` [tip:x86/boot] " tip-bot for Eric W. Biederman
2012-07-01 15:04 ` [PATCH 2/2] " H. Peter Anvin
2012-07-01 15:34 ` H. Peter Anvin
2012-07-01 16:08 ` Eric W. Biederman
2012-07-01 16:11 ` H. Peter Anvin
2012-07-01 16:26 ` Eric W. Biederman
2012-07-01 16:44 ` H. Peter Anvin
2012-07-01 17:09 ` Eric W. Biederman
2012-07-01 17:15 ` H. Peter Anvin
2012-07-01 18:25 ` Eric W. Biederman
2012-07-01 18:37 ` H. Peter Anvin [this message]
2012-07-01 19:20 ` Eric W. Biederman
2012-07-01 19:23 ` H. Peter Anvin
2012-07-01 20:40 ` Eric W. Biederman
2012-07-01 20:52 ` H. Peter Anvin
2012-07-09 6:50 ` Eric W. Biederman
2012-07-09 6:52 ` [PATCH 1/4] x86 boot: Jump to the entry point address in the elf header Eric W. Biederman
2012-07-09 6:53 ` [PATCH 2/4] x86 boot: Optimize the elf header handling Eric W. Biederman
2012-07-09 6:55 ` [PATCH 3/4] x86 boot: When building vmlinux.bin properly precompute the memory image Eric W. Biederman
2012-07-09 6:56 ` [PATCH 4/4] x86 boot: Tell ld the kernel doesn't want 2MB file offset alignment Eric W. Biederman
2012-07-09 6:59 ` [PATCH 1/4] x86 boot: Jump to the entry point address in the elf header Eric W. Biederman
2012-07-02 16:56 ` [PATCH 2/2] x86, boot: Optimize the elf header handling Tejun Heo
2012-07-09 7:03 ` Eric W. Biederman
2012-07-01 2:23 ` [PATCH 1/2] x86, boot: Don't overlap the compressed and non-compressed image Eric W. Biederman
2012-07-01 2:32 ` H. Peter Anvin
2012-07-01 5:22 ` Eric W. Biederman
2012-07-01 14:55 ` [tip:x86/boot] x86, boot: Don' t " tip-bot for Eric W. Biederman
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