From: "H. Peter Anvin" <hpa@zytor.com>
To: Borislav Petkov <bp@amd64.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
Ingo Molnar <mingo@kernel.org>,
Thomas Gleixner <tglx@linutronix.de>
Subject: Re: [PATCH 3/3] x86, extable: Handle early exceptions
Date: Thu, 19 Apr 2012 10:59:23 -0700 [thread overview]
Message-ID: <4F90527B.7020005@zytor.com> (raw)
In-Reply-To: <20120419173802.GI3221@aftab.osrc.amd.com>
On 04/19/2012 10:38 AM, Borislav Petkov wrote:
>
> Yeah, simplicity is the key here. I don't think we're getting that many
> early boot exceptions due to rdmsr or whatever to warrant adding a bunch
> of code.
>
> OTOH, if we can share early and normal exception handling lookup code, then a
> perfect hash would make sense as those exceptions would pile up.
>
Obviously we should use the hash after the main kernel is up, too.
Anything else would be silly.
I would argue that the O(1) hash makes things simpler as there is no
need to deal with collisions at all. The one advantage with "plain"
hashes is that can be runtime modified, which would be of some interest
if we create one single hash table that includes modules.
*That* seems complex to me, though.
-hpa
next prev parent reply other threads:[~2012-04-19 17:59 UTC|newest]
Thread overview: 43+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-04-19 0:16 [PATCH 0/5] RFC: x86: Early exception table support H. Peter Anvin
2012-04-19 0:16 ` [PATCH 1/5] x86, nop: Make the ASM_NOP* macros work from assembly H. Peter Anvin
2012-04-19 9:29 ` Borislav Petkov
2012-04-20 0:24 ` [tip:x86/extable] " tip-bot for H. Peter Anvin
2012-04-19 0:16 ` [PATCH 2/5] x86: Add symbolic constant for exceptions with error code H. Peter Anvin
2012-04-19 9:30 ` Borislav Petkov
2012-04-20 0:25 ` [tip:x86/extable] " tip-bot for H. Peter Anvin
2012-04-19 0:16 ` [PATCH 3/5] x86, paravirt: Replace GET_CR2_INTO_RCX with GET_CR2_INTO_RAX H. Peter Anvin
2012-04-20 0:26 ` [tip:x86/extable] " tip-bot for H. Peter Anvin
2012-04-19 0:16 ` [PATCH 4/5] x86-64: Handle exception table entries during early boot H. Peter Anvin
2012-04-19 13:02 ` Borislav Petkov
2012-04-19 16:59 ` H. Peter Anvin
2012-04-19 17:16 ` Borislav Petkov
2012-04-20 0:29 ` [tip:x86/extable] x86, doc: Revert "x86: Document rdmsr_safe restrictions" tip-bot for H. Peter Anvin
2012-04-20 0:28 ` [tip:x86/extable] x86-64: Handle exception table entries during early boot tip-bot for H. Peter Anvin
2012-04-19 0:16 ` [PATCH 5/5] x86-32: " H. Peter Anvin
2012-04-20 0:28 ` [tip:x86/extable] " tip-bot for H. Peter Anvin
2012-04-19 9:22 ` [PATCH 0/5] RFC: x86: Early exception table support Borislav Petkov
2012-04-19 9:24 ` [PATCH 1/3] x86, extable: Cleanup fixup_exception Borislav Petkov
2012-04-19 9:25 ` [PATCH 2/3] x86, extable: Carve out the main extable searching routine Borislav Petkov
2012-04-19 9:26 ` [PATCH 3/3] x86, extable: Handle early exceptions Borislav Petkov
2012-04-19 17:02 ` H. Peter Anvin
2012-04-19 17:27 ` Linus Torvalds
2012-04-19 17:38 ` Borislav Petkov
2012-04-19 17:59 ` H. Peter Anvin [this message]
2012-04-19 18:25 ` Linus Torvalds
2012-04-19 18:55 ` H. Peter Anvin
2012-04-19 20:17 ` David Daney
2012-04-19 20:20 ` H. Peter Anvin
2012-04-19 20:26 ` H. Peter Anvin
2012-04-19 20:40 ` David Daney
2012-04-19 21:47 ` Linus Torvalds
2012-04-19 22:16 ` H. Peter Anvin
2012-04-19 22:47 ` Tony Luck
2012-04-19 22:58 ` Linus Torvalds
2012-04-19 23:10 ` H. Peter Anvin
2012-04-19 23:26 ` Tony Luck
2012-04-19 23:35 ` H. Peter Anvin
2012-04-20 8:26 ` Andreas Schwab
2012-04-19 18:11 ` Linus Torvalds
2012-04-20 8:46 ` Borislav Petkov
2012-04-19 17:54 ` H. Peter Anvin
2012-04-20 0:27 ` [tip:x86/extable] x86, extable: Add early_fixup_exception() tip-bot for H. Peter Anvin
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