d/freebsd-dev
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

loader: zfs reader should not probe partitionless disks

Browse Source 
First of all, normal setups can not boot such pools as the tools
do not support installing boot programs.

Secondly, for proper pool configuration detection, we need to checks all
four label copies on disk, 2 from front and 2 from the end of the disk,
but zfs label does not contain the size of the disk - so we depend on
firmware to report the correct disk size or use information from the
partition table.

Without partition table, we only can rely on firmware to report and support
disk IO properly.

There is a specific case: 8TB disks are reported by BIOS to have 4294967295
sectors (0x00000000ffffffff), the sectors reported by OS is 15628053168
(0x00000003a3812ab0), so the reported size is less than actual but is hitting
32-bit max. Unfortuantely the real limit must be even lower because probing
this disk in this system will wnd up with hung system.

UEFI boot of this system seems not to be affected.

Reviewed by:	imp
MFC after:	2 weeks
Differential Revision:	https://reviews.freebsd.org/D18558
This commit is contained in:
Toomas Soome 2018-12-16 08:58:14 +00:00
parent 0060ae1876
commit 1309bed839
Notes: svn2git 2020-12-20 02:59:44 +00:00 
svn path=/head/; revision=342151
1 changed files with 5 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
stand/libsa/zfs/zfs.c
View File

@ -527,10 +527,11 @@ zfs_probe_dev(const char *devname, uint64_t *pool_guid)
pa.fd = open(devname, O_RDONLY);
if (pa.fd == -1)
return (ENXIO);
/* Probe the whole disk */
ret = zfs_probe(pa.fd, pool_guid);
if (ret == 0)
return (0);
/*
* We will not probe the whole disk, we can not boot from such
* disks and some systems will misreport the disk sizes and will
* hang while accessing the disk.
*/
/* Probe each partition */
ret = ioctl(pa.fd, DIOCGMEDIASIZE, &mediasz);