diff options
2 files changed, 10 insertions, 0 deletions
diff --git a/init/do_mounts.c b/init/do_mounts.c
index 3715feb8446..d055b1914c3 100644
--- a/init/do_mounts.c
+++ b/init/do_mounts.c
@@ -263,6 +263,10 @@ retry:
printk("Please append a correct \"root=\" boot option; here are the available partitions:\n");
+ printk("DEBUG_BLOCK_EXT_DEVT is enabled, you need to specify "
+ "explicit textual name for \"root=\" boot option.\n");
panic("VFS: Unable to mount root fs on %s", b);
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 4378d5e923c..c556896abe5 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -638,6 +638,12 @@ config DEBUG_BLOCK_EXT_DEVT
userland code paths which assume predetermined contiguous
device number allocation.
+ Note that turning on this debug option shuffles all the
+ device numbers for all IDE and SCSI devices including libata
+ ones, so root partition specified using device number
+ directly (via rdev or root=MAJ:MIN) won't work anymore.
+ Textual device names (root=/dev/sdXn) will continue to work.
Say N if you are unsure.
config LKDTM