From: "H. Peter Anvin" <hpa@zytor.com>
To: Tirumala Reddy Marri <tmarri@amcc.com>
Cc: linux-raid@vger.kernel.org
Subject: Re: RAID-6 polynomial
Date: Thu, 22 Apr 2010 22:43:57 -0700 [thread overview]
Message-ID: <4BD1339D.3040506@zytor.com> (raw)
In-Reply-To: <AC5E1C3367E37D44970B81A6ADD1DA2C09439F92@SDCEXCHANGE01.ad.amcc.com>
On 04/22/2010 09:14 PM, Tirumala Reddy Marri wrote:
>
> Is there a reason for hard coding 0x11d as polynomial ? The problem I
> ran into was when I was trying disk fail test there was issue in
> recovering the data. Then it turned out to be ADMA was using polynomial
> 0x14d and SW algorithm was using 0x11d. This was because syndrome
> calculated using DMA engine and recovery done using SW api.
>
Yes, it would mean the on-disk format would be incompatible otherwise.
Everyone needs to use the same polynomial.
-hpa
--
H. Peter Anvin, Intel Open Source Technology Center
I work for Intel. I don't speak on their behalf.
prev parent reply other threads:[~2010-04-23 5:43 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-04-19 23:44 RAID-6 polynomial Tirumala Reddy Marri
2010-04-20 1:55 ` Michael Evans
2010-04-20 3:14 ` Tirumala Reddy Marri
2010-04-20 4:39 ` Michael Evans
2010-04-22 1:00 ` H. Peter Anvin
2010-04-23 4:14 ` Tirumala Reddy Marri
2010-04-23 5:43 ` H. Peter Anvin [this message]
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