From 39d90012a652fa4d9d2534d0168ddad8cacec248 Mon Sep 17 00:00:00 2001

From: Kairui Song <kasong@redhat.com>

Date: Thu, 10 Sep 2020 02:18:02 +0800

Subject: [PATCH] 04watchdog: split the watchdog module install

In some cases, user only want to include the watchdog module, not the

wdctl or any other userspace helper. For example, systemd have a

RebootWatchdogSec option that use watchdog to prevent reboot hangs. And

it can help prevent machines hangs when reboot directly within the

initramfs stage. So split the module installation to a standlone module.

Also when watchdog-module get included, install driver for all loaded

watchdog instaed of only install driver for active watchdog. Both

watchdog and watchdog-module return 255 in check(), so it's enabled only

when manually included, the watchdog may get configured/activated later.

Signed-off-by: Kairui Song <kasong@redhat.com>

---

 modules.d/04watchdog-modules/module-setup.sh | 61 ++++++++++++++++++++++++++++

 modules.d/04watchdog/module-setup.sh         | 50 +----------------------

 2 files changed, 63 insertions(+), 48 deletions(-)

diff --git a/modules.d/04watchdog-modules/module-setup.sh b/modules.d/04watchdog-modules/module-setup.sh

new file mode 100755

index 00000000..5fbd769b

--- /dev/null

+++ b/modules.d/04watchdog-modules/module-setup.sh

@@ -0,0 +1,61 @@

+#!/bin/bash

+

+# called by dracut

+check() {

+    return 255

+}

+

+# called by dracut

+depends() {

+    return 0

+}

+

+# called by dracut

+install() {

+    return 0

+}

+

+installkernel() {

+    local -A _drivers

+    local _alldrivers _wdtdrv _wdtppath _dir

+    [[ -d /sys/class/watchdog/ ]] || return

+    for _dir in /sys/class/watchdog/*; do

+        [[ -d "$_dir" ]] || continue

+        [[ -f "$_dir/state" ]] || continue

+        # device/modalias will return driver of this device

+        _wdtdrv=$(< "$_dir/device/modalias")

+        # There can be more than one module represented by same

+        # modalias. Currently load all of them.

+        # TODO: Need to find a way to avoid any unwanted module

+        # represented by modalias

+        _wdtdrv=$(modprobe --set-version "$kernel" -R $_wdtdrv 2>/dev/null)

+        if [[ $_wdtdrv ]]; then

+            instmods $_wdtdrv

+            for i in $_wdtdrv; do

+                _drivers[$i]=1

+            done

+        fi

+        # however in some cases, we also need to check that if there is

+        # a specific driver for the parent bus/device.  In such cases

+        # we also need to enable driver for parent bus/device.

+        _wdtppath=$(readlink -f "$_dir/device")

+        while [[ -d "$_wdtppath" ]] && [[ "$_wdtppath" != "/sys" ]]; do

+            _wdtppath=$(readlink -f "$_wdtppath/..")

+            [[ -f "$_wdtppath/modalias" ]] || continue

+

+            _wdtdrv=$(< "$_wdtppath/modalias")

+            _wdtdrv=$(modprobe --set-version "$kernel" -R $_wdtdrv 2>/dev/null)

+            if [[ $_wdtdrv ]]; then

+                instmods $_wdtdrv

+                for i in $_wdtdrv; do

+                    _drivers[$i]=1

+                done

+            fi

+        done

+    done

+    # ensure that watchdog module is loaded as early as possible

+    _alldrivers="${!_drivers[*]}"

+    [[ $_alldrivers ]] && echo "rd.driver.pre=${_alldrivers// /,}" > ${initdir}/etc/cmdline.d/00-watchdog.conf

+

+    return 0

+}

diff --git a/modules.d/04watchdog/module-setup.sh b/modules.d/04watchdog/module-setup.sh

index 7566d651..15bcd897 100755

--- a/modules.d/04watchdog/module-setup.sh

+++ b/modules.d/04watchdog/module-setup.sh

@@ -7,7 +7,7 @@ check() {

 # called by dracut

 depends() {

-    return 0

+    return "watchdog-modules"

 }

 # called by dracut

@@ -27,53 +27,7 @@ install() {

         inst_hook cleanup   00 "$moddir/watchdog.sh"

         inst_hook cleanup   99 "$moddir/watchdog.sh"

     fi

+

     inst_hook emergency 02 "$moddir/watchdog-stop.sh"

     inst_multiple -o wdctl

 }

-

-installkernel() {

-    local -A _drivers

-    local _alldrivers _active _wdtdrv _wdtppath _dir

-    [[ -d /sys/class/watchdog/ ]] || return

-    for _dir in /sys/class/watchdog/*; do

-        [[ -d "$_dir" ]] || continue

-        [[ -f "$_dir/state" ]] || continue

-        _active=$(< "$_dir/state")

-        ! [[ $hostonly ]] || [[ "$_active" =  "active" ]] || continue

-        # device/modalias will return driver of this device

-        _wdtdrv=$(< "$_dir/device/modalias")

-        # There can be more than one module represented by same

-        # modalias. Currently load all of them.

-        # TODO: Need to find a way to avoid any unwanted module

-        # represented by modalias

-        _wdtdrv=$(modprobe --set-version "$kernel" -R $_wdtdrv 2>/dev/null)

-        if [[ $_wdtdrv ]]; then

-            instmods $_wdtdrv

-            for i in $_wdtdrv; do

-                _drivers[$i]=1

-            done

-        fi

-        # however in some cases, we also need to check that if there is

-        # a specific driver for the parent bus/device.  In such cases

-        # we also need to enable driver for parent bus/device.

-        _wdtppath=$(readlink -f "$_dir/device")

-        while [[ -d "$_wdtppath" ]] && [[ "$_wdtppath" != "/sys" ]]; do

-            _wdtppath=$(readlink -f "$_wdtppath/..")

-            [[ -f "$_wdtppath/modalias" ]] || continue

-

-            _wdtdrv=$(< "$_wdtppath/modalias")

-            _wdtdrv=$(modprobe --set-version "$kernel" -R $_wdtdrv 2>/dev/null)

-            if [[ $_wdtdrv ]]; then

-                instmods $_wdtdrv

-                for i in $_wdtdrv; do

-                    _drivers[$i]=1

-                done

-            fi

-        done

-    done

-    # ensure that watchdog module is loaded as early as possible

-    _alldrivers="${!_drivers[*]}"

-    [[ $_alldrivers ]] && echo "rd.driver.pre=${_alldrivers// /,}" > ${initdir}/etc/cmdline.d/00-watchdog.conf

-

-    return 0

-}