Date: Tue, 30 Mar 2021 00:06:43 +0000 From: bugzilla-noreply@freebsd.org To: bugs@FreeBSD.org Subject: [Bug 254649] 12.2-RELEASE: possible memory overrun in the loader(8) Message-ID: <bug-254649-227@https.bugs.freebsd.org/bugzilla/>
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https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D254649 Bug ID: 254649 Summary: 12.2-RELEASE: possible memory overrun in the loader(8) Product: Base System Version: 12.2-RELEASE Hardware: Any OS: Any Status: New Severity: Affects Some People Priority: --- Component: kern Assignee: bugs@FreeBSD.org Reporter: eugen@freebsd.org CC: imp@FreeBSD.org, kevans@freebsd.org, tsoome@freebsd.org Hi! I've found that adding loading of several kernel modules to /boot/loader.co= nf can result in failure to mount ZFS root file system at boot time and going = to=20 mountroot> prompt. I've faced to problem after successfully installing and running FreeBSD 12.2/amd64 as VM guest at some hoster providing cheap 1GB RAM/20GB HDD plan. I've reproduced the problem using my own VirtualBox. How to repeat: Use any hypervisor to create new VM for FreeBSD 12.2-RELEASE/amd64 with 102= 4MB RAM and 20GB HDD (thin provisioning is OK, network is not required nor used= ). Attach official FreeBSD-12.2-RELEASE-amd64-disc1.iso image to virtual CD and boot it. Do not use bsdinstall installation procedures but enter Shell dire= ctly to perform installation this way (maybe replace ada0 with da0 or vtbd0 depending on hypervisor): # make MBR with two slices, first one for swap (2GB), the rest for ZFS boot pool gpart destroy -F ada0 gpart create -s MBR ada0 gpart add -b 504 -t freebsd -s 2g ada0 glabel label swap ada0s1 gpart add -t freebsd ada0 # install bootloaders according to zfsboot(8) manual page gpart bootcode -b /boot/boot0 ada0 gpart set -a active -i 2 ada0 boot0cfg -s 2 ada0 dd if=3D/dev/zero of=3D/dev/ada0s2 count=3D2 dd if=3D/boot/zfsboot of=3D/dev/ada0s2 count=3D1 dd if=3D/boot/zfsboot of=3D/dev/ada0s2 iseek=3D1 oseek=3D1024 # create and populate ZFS boot pool named "os" zpool create -f -O reservation=3D100m -O compression=3Dlz4 -O atime=3Doff -= m / -R /mnt os /dev/ada0s2 cd /mnt tar xf /usr/freebsd-dist/kernel.txz tar xf /usr/freebsd-dist/base.txz cat > boot/loader.conf <<EOF kern.vty=3Dsc beastie_disable=3D"YES" autoboot_delay=3D"6" hw.memtest.tests=3D0 zfs_load=3D"YES" vfs.root.mountfrom=3D"zfs:os" dumpdev=3D"/dev/label/swap" EOF cat > etc/rc.conf <<EOF hostname=3D"test.localdomain" zfs_enable=3D"YES" EOF cat > etc/fstab <<EOF # Device Mountpoint FStype Options Dump Pass# /dev/label/swap none swap sw 0 0 EOF cd / umount -f /mnt zpool export os halt -p Now the system is ready to boot off emulated HDD. Reconfigure the VM to boot off HDD instead of CD and boot it. It should boot to multiuser just fine. Now add 4 lines to /boot/loader.conf: aesni_load=3D"YES" mac_portacl_load=3D"YES" dummynet_load=3D"YES" libalias_load=3D"YES" Reboot the VM and see the failure: Mounting from zfs:os failed with error 5; retrying for more 3 seconds Mounting from zfs:os failed with error 5. ... mountroot> To recover, one needs to escape to loader prompt at boot time and use "unlo= ad" command then manually load kernel, opensolaris.ko and zfs.ko then proceed w= ith booting. --=20 You are receiving this mail because: You are the assignee for the bug.=
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