diff options
| author | наб <[email protected]> | 2023-03-31 18:47:48 +0200 |
|---|---|---|
| committer | GitHub <[email protected]> | 2023-03-31 09:47:48 -0700 |
| commit | 3399a30ee02d0d31ba2d43d0ce0a2fd90d5c575d (patch) | |
| tree | a7810c367a5acb2d0363040e0c6e47edee3b0ebb /man/man7 | |
| parent | c5431f14655ce05d1ea99cb012806f0e5873d257 (diff) | |
contrib: dracut: fix race with root=zfs:dset when necessities required
This had always worked in my testing, but a user on hardware reported
this to happen 100%, and I reproduced it once with cold VM host caches.
dracut-zfs-generator runs as a systemd generator, i.e. at Some
Relatively Early Time; if root= is a fixed dataset, it tries to
"solve [necessities] statically at generation time".
If by that point zfs-import.target hasn't popped (because the import is
taking a non-negligible amount of time for whatever reason), it'll see
no children for the root datase, and as such generate no mounts.
This has never had any right to work. No-one caught this earlier because
it's just that much more convenient to have root=zfs:AUTO, which orders
itself properly.
To fix this, always run zfs-nonroot-necessities.service;
this additionally simplifies the implementation by:
* making BOOTFS from zfs-env-bootfs.service be the real, canonical,
root dataset name, not just "whatever the first bootfs is",
and only set it if we're ZFS-booting
* zfs-{rollback,snapshot}-bootfs.service can use this instead of
re-implementing it
* having zfs-env-bootfs.service also set BOOTFSFLAGS
* this means the sysroot.mount drop-in can be fixed text
* zfs-nonroot-necessities.service can also be constant and always
enabled, because it's conditioned on BOOTFS being set
There is no longer any code generated at run-time
(the sysroot.mount drop-in is an unavoidable gratuitous cp).
The flow of BOOTFS{,FLAGS} from zfs-env-bootfs.service to sysroot.mount
is not noted explicitly in dracut.zfs(7), because (a) at some point it's
just visual noise and (b) it's already ordered via d-p-m.s from z-i.t.
Reviewed-by: Brian Behlendorf <[email protected]>
Signed-off-by: Ahelenia Ziemiańska <[email protected]>
Closes #14690
Diffstat (limited to 'man/man7')
| -rw-r--r-- | man/man7/dracut.zfs.7 | 16 |
1 files changed, 8 insertions, 8 deletions
diff --git a/man/man7/dracut.zfs.7 b/man/man7/dracut.zfs.7 index 2db2f6639..c1475c695 100644 --- a/man/man7/dracut.zfs.7 +++ b/man/man7/dracut.zfs.7 @@ -1,6 +1,6 @@ .\" SPDX-License-Identifier: 0BSD .\" -.Dd April 4, 2022 +.Dd March 28, 2023 .Dt DRACUT.ZFS 7 .Os . @@ -28,13 +28,13 @@ zfs-import-scan.service \(da \(da | zfs-import-c zfs-import.target \(-> dracut-pre-mount.service | \(ua | | dracut-zfs-generator | - | ____________________/| + | _____________________/| |/ \(da - | sysroot.mount \(<-\(em\(em\(em\(em\(em\(em\(em\(em\(em\(em\(em\(em\(em\(em dracut-zfs-generator - | | \(da | - | \(da sysroot-{usr,etc,lib,&c.}.mount | - | initrd-root-fs.target \(<-\(em\(em\(em\(em\(em\(em\(em\(em\(em\(em\(em\(em or \(da - | | zfs-nonroot-necessities.service + | sysroot.mount \(<-\(em\(em\(em dracut-zfs-generator + | | + | \(da + | initrd-root-fs.target \(<-\(em zfs-nonroot-necessities.service + | | | | \(da | \(da dracut-mount.service | zfs-snapshot-bootfs.service | | @@ -42,7 +42,7 @@ zfs-import-scan.service \(da \(da | zfs-import-c \(da … | zfs-rollback-bootfs.service | | | \(da | - | sysroot-usr.mount \(<-\(em\(em\(em\(em\(em\(em\(em\(em\(em\(em\(em\(em\(em\(em\(em\(em\(em\(em\(em\(em\(em\(em\(em/ + | /sysroot/{usr,etc,lib,&c.} \(<-\(em\(em\(em\(em\(em\(em\(em\(em\(em\(em\(em\(em\(em\(em\(em\(em\(em\(em\(em/ | | | \(da | initrd-fs.target |