From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on inbox.vuxu.org X-Spam-Level: X-Spam-Status: No, score=-1.1 required=5.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HTML_MESSAGE,MAILING_LIST_MULTI,T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.4 Received: (qmail 9914 invoked from network); 10 Jun 2023 14:51:58 -0000 Received: from tb-ob0.topicbox.com (64.147.108.117) by inbox.vuxu.org with ESMTPUTF8; 10 Jun 2023 14:51:58 -0000 Received: from tb-mx1.topicbox.com (tb-mx1.nyi.icgroup.com [10.90.30.61]) by tb-ob0.topicbox.com (Postfix) with ESMTP id E86DF24C9C for ; Sat, 10 Jun 2023 10:51:55 -0400 (EDT) (envelope-from bounce.mMb36b2ccec84dc4eb9d0a8c21.r522be890-2105-11eb-b15e-8d699134e1fa@9fans.bounce.topicbox.com) Received: by tb-mx1.topicbox.com (Postfix, from userid 1132) id E4C2B1CCAF1B; Sat, 10 Jun 2023 10:51:55 -0400 (EDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed; d=9fans.net; h=to :message-id:date:mime-version:content-type :content-transfer-encoding:list-help:list-id:list-post :list-subscribe:reply-to:subject:from:list-unsubscribe; s= dkim-1; t=1686408715; x=1686495115; bh=bFkfb72Aroma+eKQFJAA26yv4 wDfx+oxOczUjUNQWGw=; b=T0E6JTY+Js9UkPLU7wDAECAUVaahzhtHdlY2YUJvo iRx4XX4oVt92qZMIrsl2Dg/eoq5eT2tp2wPFl3HR1M99825Wzu0yARhVOFPucuNU d4heyD078ZqPJXz9o00hMrLTjjnyQafKBmFDOFf98Kn0cEfTc0SX7o8nz/XSZ7xD oU= To: 9fans <9fans@9fans.net> Message-Id: <16864087040.35AF.257747@composer.9fans.topicbox.com> Date: Sat, 10 Jun 2023 10:51:44 -0400 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary=16864087041.91B0C5885.257747 Content-Transfer-Encoding: 7bit Topicbox-Policy-Reasoning: allow: sender is a member Topicbox-Message-UUID: 517aa4ae-079e-11ee-b7bd-5344262d11b0 Archived-At: =?UTF-8?B?PGh0dHBzOi8vOWZhbnMudG9waWNib3guY29tL2dyb3Vwcy85?= =?UTF-8?B?ZmFucy9UMjI5OGY1MmZjMzI0Y2ZmOS1NYjM2YjJjY2VjODRkYzRlYjlkMGE4?= =?UTF-8?B?YzIxPg==?= List-Help: List-Id: "9fans" <9fans.9fans.net> List-Post: List-Software: Topicbox v0 List-Subscribe: Precedence: list Reply-To: 9fans <9fans@9fans.net> Subject: [9fans] bug report : disk/fdisk From: "ibrahim via 9fans" <9fans@9fans.net> List-Unsubscribe: , Topicbox-Delivery-ID: 2:9fans:437d30aa-c441-11e9-8a57-d036212d11b0:522be890-2105-11eb-b15e-8d699134e1fa:Mb36b2ccec84dc4eb9d0a8c21:1:lAiSdwxFJeJIhKCMVB27PEB9xM6o_6uu30RZYbKRY2k --16864087041.91B0C5885.257747 Date: Sat, 10 Jun 2023 10:51:44 -0400 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable After creating an image file with : dd disk/mbr disk/fdisk disk/prep the resulting partition table in the mbr=C2=A0 is buggy : the chs values in the mbr are incompatible with bios. bios uses the formula (c*H+h)*S+s-1 to calculate the lba values with H=3D25= 6, S=3D63 while c (cylinder), h(head), s(sector) are the values from chs en= tries in the mbr partition table. disk/fdisk uses the same formula while setting H=3D64, S=3D32. If you write this image to real Hardware (HDD, USB-Sticks) some bios won't = boot from such media especially if your boot drive has a size less than 8GB= cause for media with sizes less than this size some bios'es use CHS addres= sing and some verify that sector id's from chs and lba are equal. ------------------------------------------ 9fans: 9fans Permalink: https://9fans.topicbox.com/groups/9fans/T2298f52fc324cff9-Mb36b2= ccec84dc4eb9d0a8c21 Delivery options: https://9fans.topicbox.com/groups/9fans/subscription --16864087041.91B0C5885.257747 Date: Sat, 10 Jun 2023 10:51:44 -0400 MIME-Version: 1.0 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable

After creating an image file with :

disk/mbr

disk/fdi= sk

disk/prep

the resulting= partition table in the mbr is buggy :

the chs values in the mbr are incompatible with bios.

bios uses the formula (c*H+h)*S+s-1 to calculate the lba val= ues with H=3D256, S=3D63 while c (cylinder), h(head), s(sector) are the val= ues from chs entries in the mbr partition table.

disk/fdisk uses the same formula while setting H=3D64, S=3D32.
=

If you write this image to real Hardware (HDD, = USB-Sticks) some bios won't boot from such media especially if your boo= t drive has a size less than 8GB cause for media with sizes less than this = size some bios'es use CHS addressing and some verify that sector id'= ;s from chs and lba are equal.

= --16864087041.91B0C5885.257747--