rules: import previous SYSTEMD_READY state for suspended DM devices and skip other rules

We can't get any FS meta-data from a suspended device. Hence defer
making any plugged/unplugged decisions, i.e. we just import whatever was
previous state and skip processing all other rules.

Thanks Lennart Poettering <lennart@poettering.net> for suggesting this
solution.

1 files changed, 6 insertions, 0 deletions

diff --git a/rules.d/99-systemd.rules.in b/rules.d/99-systemd.rules.in
index 25b8a590a6..3dbba1f850 100644
--- a/rules.d/99-systemd.rules.in
+++ b/rules.d/99-systemd.rules.in
@@ -15,12 +15,18 @@ KERNEL=="vport*", TAG+="systemd"
 SUBSYSTEM=="ubi", TAG+="systemd"
 
 SUBSYSTEM=="block", TAG+="systemd"
+
+# We can't make any conclusions about suspended DM devices so let's just import previous SYSTEMD_READY state and skip other rules
+SUBSYSTEM=="block", ENV{DM_SUSPENDED}=="1", IMPORT{db}="SYSTEMD_READY", GOTO="systemd_end"
 SUBSYSTEM=="block", ACTION=="add", ENV{DM_UDEV_DISABLE_OTHER_RULES_FLAG}=="1", ENV{SYSTEMD_READY}="0"
 
 # Ignore encrypted devices with no identified superblock on it, since
 # we are probably still calling mke2fs or mkswap on it.
 SUBSYSTEM=="block", ENV{DM_UUID}=="CRYPT-*", ENV{ID_PART_TABLE_TYPE}=="", ENV{ID_FS_USAGE}=="", ENV{SYSTEMD_READY}="0"
 
+# Explicitly set SYSTEMD_READY=1 for DM devices that don't have it set yet, so that we always have something to import above
+SUBSYSTEM=="block", ENV{DM_UUID}=="?*", ENV{SYSTEMD_READY}=="", ENV{SYSTEMD_READY}="1"
+
 # add symlink to GPT root disk
 SUBSYSTEM=="block", ENV{ID_PART_GPT_AUTO_ROOT}=="1", ENV{ID_FS_TYPE}!="crypto_LUKS", SYMLINK+="gpt-auto-root"
 SUBSYSTEM=="block", ENV{ID_PART_GPT_AUTO_ROOT}=="1", ENV{ID_FS_TYPE}=="crypto_LUKS", SYMLINK+="gpt-auto-root-luks"