From: "H. Peter Anvin" <hpa@zytor.com>
To: Adrian Bunk <bunk@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>,
Ingo Molnar <mingo@elte.hu>,
Linus Torvalds <torvalds@linux-foundation.org>,
linux-kernel@vger.kernel.org,
Thomas Gleixner <tglx@linutronix.de>,
Yinghai Lu <yinghai.lu@sun.com>,
Yinghai Lu <yhlu.kernel@gmail.com>,
jbarnes@virtuousgeek.org
Subject: Re: [git pull] "big box" x86 changes, boot protocol
Date: Sat, 26 Apr 2008 14:10:13 -0700 [thread overview]
Message-ID: <48139A35.6050608@zytor.com> (raw)
In-Reply-To: <20080426210632.GW2252@cs181133002.pp.htv.fi>
Adrian Bunk wrote:
>>> + memcpy(&early_res[i], &early_res[i + 1],
>>> + (j - 1 - i) * sizeof(struct early_res));
>> nit: memcpy() shouldn't be used for overlapping copies. It happens to be
>> OK (for dst<src) in the kernel implementations. We hope.
>> ...
>
> We always use the gcc builtin for memcpy() here.
>
You have to do something pretty weird for memcpy() to not work for
dst <= src even with overlap; this usually involves architectures that
have explicit cache control instructions to establish the dst in the
cache, if used before src is read.
This is not an issue on x86, though.
-hpa
next prev parent reply other threads:[~2008-04-26 21:10 UTC|newest]
Thread overview: 52+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-04-26 18:55 [RFC git pull] "big box" x86 changes Ingo Molnar
2008-04-26 19:05 ` Stefan Richter
2008-04-26 19:21 ` Ingo Molnar
2008-04-26 19:12 ` Linus Torvalds
2008-04-26 19:41 ` [git pull] "big box" x86 changes, bootmem/sparsemem Ingo Molnar
2008-04-26 19:52 ` Linus Torvalds
2008-04-26 20:07 ` Ingo Molnar
2008-04-26 20:08 ` [git pull] "big box" x86 changes, bootmem/sparsemem, #2 Ingo Molnar
2008-04-26 20:30 ` Linus Torvalds
2008-04-26 20:55 ` [git pull] "big box" x86 changes, bootmem/sparsemem, #3 Ingo Molnar
2008-04-27 22:48 ` [git pull] "big box" x86 changes, bootmem/sparsemem Johannes Weiner
2008-04-27 23:46 ` Ingo Molnar
2008-04-28 0:19 ` Johannes Weiner
2008-04-28 0:40 ` [patch] mm: node-setup agnostic free_bootmem() Ingo Molnar
2008-04-28 1:48 ` Yinghai Lu
2008-04-28 16:54 ` Johannes Weiner
2008-04-28 19:11 ` Yinghai Lu
2008-04-28 19:55 ` Yinghai Lu
2008-04-30 10:50 ` Johannes Weiner
2008-04-30 16:22 ` Yinghai Lu
2008-04-30 17:52 ` Johannes Weiner
2008-04-30 20:30 ` Yinghai Lu
2008-04-28 16:49 ` Johannes Weiner
2008-04-29 14:25 ` Ingo Molnar
2008-04-30 10:52 ` Johannes Weiner
2008-04-28 0:33 ` [git pull] "big box" x86 changes, bootmem/sparsemem Yinghai Lu
2008-04-28 16:58 ` Johannes Weiner
2008-04-26 19:54 ` [git pull] "big box" x86 changes, boot protocol Ingo Molnar
2008-04-26 20:39 ` Andrew Morton
2008-04-26 21:06 ` Adrian Bunk
2008-04-26 21:10 ` H. Peter Anvin [this message]
2008-04-26 21:11 ` Linus Torvalds
2008-04-26 21:17 ` Ingo Molnar
2008-04-26 23:37 ` Jeremy Fitzhardinge
2008-04-27 11:21 ` Ian Campbell
2008-04-27 19:29 ` H. Peter Anvin
2008-04-28 15:27 ` Ingo Molnar
2008-04-26 20:24 ` [RFC git pull] "big box" x86 changes, GART Ingo Molnar
2008-04-26 20:26 ` Ingo Molnar
2008-04-26 21:55 ` [git pull] "big box" x86 changes, PCI Ingo Molnar
2008-04-27 16:30 ` Jesse Barnes
2008-04-28 15:38 ` Ingo Molnar
2008-04-28 20:34 ` Jesse Barnes
2008-04-28 22:53 ` Yinghai Lu
2008-04-28 23:27 ` [PATCH] x86/pci: remove flag in pci_cfg_space_size_ext Yinghai Lu
2008-04-29 16:14 ` Jesse Barnes
2008-04-29 22:05 ` Ingo Molnar
2008-04-29 22:34 ` Jesse Barnes
2008-04-26 22:17 ` [RFC git pull] "big box" x86 changes Andi Kleen
2008-04-27 3:14 ` Yinghai Lu
2008-04-27 8:30 ` Andi Kleen
2008-04-27 8:32 ` [RFC git pull] "big box" x86 changes II Andi Kleen
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