Commit Graph
6 Commits
Author SHA1 Message Date
Javier Martinez Canillas 985a141002 grub2: Exit gracefully if the configuration has BLS enabled
Since Fedora 30 grub2 has support to populate its menu entries from the
BootLoaderSpec fragments in /boot/loader/entries, so there's no need to
generate menu entries anymore using the /etc/grub.d/15_ostree script.

But since ostree doesn't update the bootloader, it may be that the grub2
installed is an old one that doesn't have BLS support.

For new installs, GRUB_ENABLE_BLSCFG=true is set in /etc/default/grub to
tell the /etc/grub.d/10_linux script if a blscfg command has to be added
to the generated grub2 config file.

So check if BLS is enabled in /etc/default/grub and only add the entries
if that's not the case. Otherwise the menu entries will be duplicated.

The approach has the drawback that if a user sets GRUB_ENABLE_BLSCFG=true
in /etc/default/grub without updating grub2, they will get an empty menu.
Since there won't be any entries created by the 30_ostree script and the
blscfg command won't work on the older grub2.

Unfortunately there is no way to know if the installed grub2 already has
BLS support or not.

Related: https://bugzilla.redhat.com/show_bug.cgi?id=1751272#c27

Closes: #1929
Approved by: jlebon
2019-09-26 17:59:37 +00:00
Javier Martinez Canillas d42f970ed3 lib/bootconfig-parser: Always include deployment index in BLS title
If there are different deployments for the same commit version, the BLS
snippets will have the same title fields (but different version fields):

$ grep title *
ostree-1-testos.conf:title TestOS 42 20190902.0 (ostree)
ostree-2-testos.conf:title TestOS 42 20190902.0 (ostree)
ostree-3-testos.conf:title TestOS 42 20190902.0 (ostree)

But bootloaders could expect the title field to be unique for BLS files.
For example, the zipl bootloader used in the s390x architecture uses the
field to name the boot sections that are created from the BLS snippets.

So two BLS snippets having the same title would lead to zipl failing to
create the IPL boot sections because they would have duplicated names:

$ zipl
Using config file '/etc/zipl.conf'
Using BLS config file '/boot/loader/entries/ostree-3-testos.conf'
Using BLS config file '/boot/loader/entries/ostree-2-testos.conf'
Using BLS config file '/boot/loader/entries/ostree-1-testos.conf'
Error: Config file '/etc/zipl.conf': Line 0: section name 'TestOS 42 20190902.0 (ostree)' already specified

Avoid this by always including the deployment index along with the commit
version in the title field, so this will be unique even if there are BLS
files for deployments that use the same commit version:

$ grep title *
ostree-1-testos.conf:title TestOS 42 20190902.0 (ostree:2)
ostree-2-testos.conf:title TestOS 42 20190902.0 (ostree:1)
ostree-3-testos.conf:title TestOS 42 20190902.0 (ostree:0)

$ zipl
Using config file '/etc/zipl.conf'
Using BLS config file '/boot/loader/entries/ostree-3-testos.conf'
Using BLS config file '/boot/loader/entries/ostree-2-testos.conf'
Using BLS config file '/boot/loader/entries/ostree-1-testos.conf'
Building bootmap in '/boot'
Building menu 'zipl-automatic-menu'
Adding #1: IPL section 'TestOS 42 20190902.0 (ostree:0)' (default)
Adding #2: IPL section 'TestOS 42 20190902.0 (ostree:1)'
Adding #3: IPL section 'TestOS 42 20190902.0 (ostree:2)'
Preparing boot device: dasda (0120).
Done.

Closes: #1911
Approved by: cgwalters
2019-09-02 21:08:58 +00:00
Javier Martinez Canillas 2ca2b88f51 lib/bootconfig-parser: Write BLS fragment fields in a deterministic order
Currently the BLS fragments fields write is non-determinisitc. The order
of the fields will depend on how the iterator of the options GHashTable
iterates over the key/value pairs.

But some bootloaders expect the fields to be written in a certain order.
For example the zipl bootloader (used in the s390x architecture) fails to
parse BLS files if the first field is not the 'title' field, since that's
used to name the zipl boot sections that are created from the BLS files.

Write the fields in a deterministic order, following what is used in the
example file of the BootLoaderspec document:

https://systemd.io/BOOT_LOADER_SPECIFICATION

Related: https://github.com/ostreedev/ostree/issues/1888

Closes: #1904
Approved by: cgwalters
2019-08-29 12:58:43 +00:00
Javier Martinez Canillas f82f825fed lib/bootconfig-parser: Remove support to preserve comments in BLS files
OSTree has some logic to preserve comment lines in the BLS fragments, but
the BLS fragments are always created on new deployments so the comments
are never carried.

Also, OSTree never writes BLS fragments with comments so these will only
be present in BLS files that were modified outside of OSTree. Something
that should be avoided in general.

Finally, there is a bug in the logic that causes BLS files to have lines
with only a newline character.

The ostree_bootconfig_parser_parse_at() function reads the bootconfig file
using glnx_fd_readall_utf8() but this function NUL terminates the returned
string with the file contents.

So when the string is later split using '\n' as delimiter, the last token
is set to '\0' and a wrong GVariant will be added to the lines GPtrArray
in the OstreeBootconfigParser struct.

This will lead to bootconfig files that contains lines with only a newline
character, since the key in the GVariant would be set to NUL and won't be
present in the options GHashTable of the OstreeBootconfigParser struct.

So let's just remove that logic since is never used and makes BLS files to
have wrong empty lines.

Before this patch:

$ tail -n 4 /boot/loader/entries/ostree-1-testos.conf | hexdump -C
00000000  74 69 74 6c 65 20 54 65  73 74 4f 53 20 34 32 20  |title TestOS 42 |
00000010  32 30 31 39 30 38 32 34  2e 30 20 28 6f 73 74 72  |20190824.0 (ostr|
00000020  65 65 29 0a 0a 0a 0a                              |ee)....|
00000027

After this patch:

$ tail -n 4 /boot/loader/entries/ostree-1-testos.conf | hexdump -C
00000000  76 65 72 73 69 6f 6e 20  31 0a 6f 70 74 69 6f 6e  |version 1.option|
00000010  73 20 72 6f 6f 74 3d 4c  41 42 45 4c 3d 4d 4f 4f  |s root=LABEL=MOO|
00000020  20 71 75 69 65 74 20 6f  73 74 72 65 65 3d 2f 6f  | quiet ostree=/o|
00000030  73 74 72 65 65 2f 62 6f  6f 74 2e 31 2f 74 65 73  |stree/boot.1/tes|
00000040  74 6f 73 2f 61 65 34 36  34 39 36 38 30 64 33 65  |tos/ae4649680d3e|
00000050  38 33 62 32 34 65 34 37  66 38 64 66 31 30 38 31  |83b24e47f8df1081|
00000060  38 62 66 36 39 38 39 64  36 34 37 61 62 32 38 38  |8bf6989d647ab288|
00000070  64 31 63 30 39 38 30 36  65 34 61 33 36 61 34 65  |d1c09806e4a36a4e|
00000080  62 62 66 36 2f 30 0a 6c  69 6e 75 78 20 2f 6f 73  |bbf6/0.linux /os|
00000090  74 72 65 65 2f 74 65 73  74 6f 73 2d 61 65 34 36  |tree/testos-ae46|
000000a0  34 39 36 38 30 64 33 65  38 33 62 32 34 65 34 37  |49680d3e83b24e47|
000000b0  66 38 64 66 31 30 38 31  38 62 66 36 39 38 39 64  |f8df10818bf6989d|
000000c0  36 34 37 61 62 32 38 38  64 31 63 30 39 38 30 36  |647ab288d1c09806|
000000d0  65 34 61 33 36 61 34 65  62 62 66 36 2f 76 6d 6c  |e4a36a4ebbf6/vml|
000000e0  69 6e 75 7a 2d 33 2e 36  2e 30 0a 74 69 74 6c 65  |inuz-3.6.0.title|
000000f0  20 54 65 73 74 4f 53 20  34 32 20 32 30 31 39 30  | TestOS 42 20190|
00000100  38 32 34 2e 30 20 28 6f  73 74 72 65 65 29 0a     |824.0 (ostree).|
0000010f

Closes: #1904
Approved by: cgwalters
2019-08-29 12:58:43 +00:00
Javier Martinez Canillas 9f48e212a3 deploy: Change BootLoaderSpec filenames so they can be used for sorting
Currently the BLS snippets are named ostree-$ID-$VARIANT_ID-$index.conf,
but the BLS config files are actually sorted by using the version field
which is the inverse of the index.

In most places, _ostree_sysroot_read_boot_loader_configs() is used to
get the BLS files and this function already returns them sorted by the
version field. The only place where the index trailing number is used is
in the ostree-grub-generator script that lists the BLS files to populate
the grub config file.

But for some bootloaders the BLS filename is the criteria for sorting by
taking the filename as a string version. So on these bootloaders the BLS
entries will be listed in the reverse order.

To avoid that, change the BLS snippets filename to have the version field
instead of the index and also to have the version before deployment name.

Make the filenames to be of the form ostree-$version-$ID-$VARIANT_ID.conf
so the version is before the deployment name.

Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>

Closes: #1654
Approved by: cgwalters
2018-06-27 18:08:28 +00:00
Javier Martinez Canillas 25e17e0b62 ostree-grub-generator: sort BLS files by version instead of alphabetically
The ostree-grub-generator populates the grub.cfg menu entries using the
BLS config files. But it uses the ls command that by default sorts the
entries alphabetically, so the order won't be correct if there are more
than 10 deployments, i.e:

$ ls -1 /boot/loader/entries/
ostree-fedora-workstation-0.conf
ostree-fedora-workstation-10.conf
ostree-fedora-workstation-1.conf
...

So instead the -v option should be used to make ls use version sorting:

$ ls -1 -v /boot/loader/entries/
ostree-fedora-workstation-0.conf
ostree-fedora-workstation-1.conf
...
ostree-fedora-workstation-10.conf

Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>

Closes: #1653
Approved by: cgwalters
2018-06-27 14:20:29 +00:00