[PATCH] printk: Document that CONFIG_BOOT_PRINTK_DELAY required for boot_delay=

From: Bjorn Helgaas
Date: Mon Jan 23 2023 - 13:05:12 EST


From: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>

Document the fact that CONFIG_BOOT_PRINTK_DELAY must be enabled for the
"boot_delay" kernel parameter to work. Also mention that "lpj=" may be
necessary.

Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
---
Documentation/admin-guide/kernel-parameters.txt | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 6cfa6e3996cf..b0b40b6a765c 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -480,8 +480,9 @@
See Documentation/block/cmdline-partition.rst

boot_delay= Milliseconds to delay each printk during boot.
- Values larger than 10 seconds (10000) are changed to
- no delay (0).
+ Enable CONFIG_BOOT_PRINTK_DELAY and also specify
+ "lpj=". Boot_delay values larger than 10 seconds
+ (10000) are changed to no delay (0).
Format: integer

bootconfig [KNL]
--
2.25.1