Date: Sat, 08 Jan 2022 11:34:28 +0000 From: bugzilla-noreply@freebsd.org To: standards@FreeBSD.org Subject: [Bug 255072] boot (legacy): no progress beyond 'BIOS DRIVE D: is disk1' Message-ID: <bug-255072-99-oshjRYiolA@https.bugs.freebsd.org/bugzilla/> In-Reply-To: <bug-255072-99@https.bugs.freebsd.org/bugzilla/> References: <bug-255072-99@https.bugs.freebsd.org/bugzilla/>
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https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D255072 --- Comment #23 from Toomas Soome <tsoome@freebsd.org> --- (In reply to spell from comment #22) Could you post the disk properties -- actual ones you see from OS tool like gpart or such, and what you get from probing in biosdisk.c (sector size, nu= mber of sectors; I guess it is detecting EDD). The disk IO in early loader is about detecting partition type and reading partition table - what type of partitioning is used on that disk? In case of GPT, we read disk start *and* disk end to be sure there is no corruption. Secondly, disk IO is from the time we attempt to discover zfs pools, that w= ill read every candidate partition start and end (pool config has 4 copies). After that we have hopefully established our boot file system and will star= t to read loader files. Usually, when there is a problem with disk IO, we see failure while detecti= ng partitioning or, while probing for zfs pools. So, what to look for: certainly sector number for read - if we do fit inside the disk. Reading past disk end can crash many BIOS systems. Second possible issue is if the disk read will read more than we have buffer space - memory corruption. Possible way to test this guess would be to read= 1 sector at a time. We use low memory buffer space for realmode INT13 calls a= nd that memory area is 16k, so single sector read will (hopefully) not trash p= ast that buffer end... --=20 You are receiving this mail because: You are the assignee for the bug.=
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