linux-yocto-tiny-kexecboot: revert Yocto specific console check

Revert Yocto-specific : "check console device file on fs when booting".
Fix kernel panic at boot because of the missing /dev/console.

Signed-off-by: Andrea Adami <andrea.adami@gmail.com>
Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>

2 files changed, 49 insertions, 0 deletions

diff --git a/meta-initramfs/recipes-kernel/linux/linux-yocto-tiny-kexecboot/revert-check-console.patch b/meta-initramfs/recipes-kernel/linux/linux-yocto-tiny-kexecboot/revert-check-console.patch
new file mode 100644
index 000000000..5e5e8d9f9
--- /dev/null
+++ b/meta-initramfs/recipes-kernel/linux/linux-yocto-tiny-kexecboot/revert-check-console.patch
@@ -0,0 +1,47 @@
+From a74e0bf51adcc867b73fc44050eb9bde985c9cba Mon Sep 17 00:00:00 2001
+From: Andrea Adami <andrea.adami@gmail.com>
+Date: Sun, 28 Feb 2016 01:09:19 +0100
+Subject: [PATCH] main.c: revert check on console device
+
+Fix kernel panic because of the missing /dev/console.
+
+Revert Yocto-specific : "check console device file on fs when booting".
+
+The initramfs used in this kernel needs to be of the smallest possible
+size so we save a few kb by deploying an empty /dev which is populated
+after boot by the init (kexecboot checks and recreates the devices
+with or without devtmpfs).
+
+Signed-off-by: Andrea Adami <andrea.adami@gmail.com>
+---
+ init/main.c | 7 -------
+ 1 file changed, 7 deletions(-)
+
+diff --git a/init/main.c b/init/main.c
+index d191d2a..9e64d70 100644
+--- a/init/main.c
++++ b/init/main.c
+@@ -976,7 +976,6 @@ static int __ref kernel_init(void *unused)
+ 
+ static noinline void __init kernel_init_freeable(void)
+ {
+-       struct stat console_stat;
+        /*
+         * Wait until kthreadd is all set-up.
+         */
+@@ -1008,12 +1007,6 @@ static noinline void __init kernel_init_freeable(void)
+ 
+        do_basic_setup();
+ 
+-       /* Use /dev/console to infer if the rootfs is setup properly */
+-       if (sys_newlstat((char __user *) "/dev/console", (struct stat __user *) &console_stat)
+-                       || !S_ISCHR(console_stat.st_mode)) {
+-               panic("/dev/console is missing or not a character device!\nPlease ensure your rootfs is properly configured\n");
+-       }
+-
+        /* Open the /dev/console on the rootfs, this should never fail */
+        if (sys_open((const char __user *) "/dev/console", O_RDWR, 0) < 0)
+                pr_err("Warning: unable to open an initial console.\n");
+-- 
+1.9.1
+
diff --git a/meta-initramfs/recipes-kernel/linux/linux-yocto-tiny-kexecboot_4.4.bb b/meta-initramfs/recipes-kernel/linux/linux-yocto-tiny-kexecboot_4.4.bb
index 2904ab6b3..fed62a926 100644
--- a/meta-initramfs/recipes-kernel/linux/linux-yocto-tiny-kexecboot_4.4.bb
+++ b/meta-initramfs/recipes-kernel/linux/linux-yocto-tiny-kexecboot_4.4.bb
@@ -1,6 +1,8 @@
 require recipes-kernel/linux/linux-yocto-tiny_${PV}.bb
 SUMMARY = "Yocto tiny kernel embedding a minimalistic kexecboot initramfs"
 
+SRC_URI += "file://revert-check-console.patch"
+
 PACKAGES = ""
 PROVIDES = ""