From b711bc3440322872aaca9db6ec3db60d9c88e3a3 Mon Sep 17 00:00:00 2001
From: Steve Mokris <steve@kosada.com>
Date: Wed, 6 Apr 2022 20:04:19 -0400
Subject: [PATCH 1/2] Add workaround for 90 second LX systemd stop/reboot delay

On SmartOS LX, systemd uses its "legacy cgroup hierarchy" (cgroup-v1)
codepath, which does not signal when the root cgroup becomes empty,
causing it to wait 90 seconds before continuing to shut down.

This commit modifies vmadm to send the `systemd-shutdown` process
SIGCHLD every second during a `vmadm stop` or `vmadm reboot` command,
which causes `systemd-shutdown` to re-check its list of remaining
processes, which removes the unnecessary wait.
---
 src/vm/node_modules/VM.js | 40 +++++++++++++++++++++++++++++++--------
 1 file changed, 32 insertions(+), 8 deletions(-)

diff --git a/src/vm/node_modules/VM.js b/src/vm/node_modules/VM.js
index e75f44478..8eeb89188 100644
--- a/src/vm/node_modules/VM.js
+++ b/src/vm/node_modules/VM.js
@@ -17641,11 +17641,16 @@ function doShutdownStop(vmobj, options, callback)
                 cb();
             });
         }, function waitInstalled(cb) {
-            VM.waitForZoneState(vmobj, 'installed', {timeout: STOP_TIMEOUT},
-                function shutdownWaitCb(err) {
-
-                if (err && err.hasOwnProperty('code')
-                    && err.code === 'ETIMEOUT') {
+            var stop_timeout = Date.now(0) + STOP_TIMEOUT * 1000;
+            var ival = setInterval(function () {
+                // Every second, tell `systemd-shutdown` to re-check
+                // its list of remaining processes.
+                // (By default, `systemd-shutdown` waits 90 seconds
+                // for a root cgroup SIGCHLD that is never sent.)
+                killSig(vmobj.pid, 'SIGCHLD');
+
+                if (Date.now(0) > stop_timeout) {
+                    clearInterval(ival);
 
                     log.info('Timeout waiting for shutdown to complete; '
                         + 'halting.');
@@ -17660,10 +17665,22 @@ function doShutdownStop(vmobj, options, callback)
                             }
                             cb(_err);
                         });
-                    return;
                 }
-                cb(err);
-            });
+
+                var load_opts = {fields: ['zone_state'], log: log};
+                vmload.getVmobj(vmobj.uuid, load_opts, function (_err, vmobj) {
+                    if (_err) {
+                        log.warn({err: _err, stdout: fds.stdout,
+                            stderr: fds.stderr}, 'Error checking status while halting zone');
+                        return;
+                    }
+
+                    if (vmobj.zone_state == 'installed') {
+                        clearInterval(ival);
+                        cb();
+                    }
+                });
+            }, 1000);
         }, function zonecfgNoAutoboot(cb) {
             zonecfg(vmobj.uuid, [unset_autoboot], {log: log},
                 function (err, fds) {
@@ -18213,6 +18230,13 @@ function doReboot(vmobj, options, callback)
         }
         ticks = 180 * 10; // (180 * 10) 100ms ticks = 3m
         ival = setInterval(function () {
+            if (ticks % 10 == 0) {
+              // Every second, tell `systemd-shutdown` to re-check
+              // its list of remaining processes.
+              // (By default, `systemd-shutdown` waits 90 seconds
+              // for a root cgroup SIGCHLD that is never sent.)
+              killSig(vmobj.pid, 'SIGCHLD');
+            }
             if (reboot_complete) {
                 log.debug('reboot marked complete, cleaning up');
                 clearInterval(ival);

From ed6eb46468950a0aaf9d0c88d071c95c527f3ba4 Mon Sep 17 00:00:00 2001
From: Steve Mokris <steve@kosada.com>
Date: Wed, 6 Apr 2022 21:40:06 -0400
Subject: [PATCH 2/2] Ensure vmobj.pid is systemd-shutdown before sending
 SIGCHLD

---
 src/vm/node_modules/VM.js | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/src/vm/node_modules/VM.js b/src/vm/node_modules/VM.js
index 8eeb89188..96e680716 100644
--- a/src/vm/node_modules/VM.js
+++ b/src/vm/node_modules/VM.js
@@ -17647,7 +17647,12 @@ function doShutdownStop(vmobj, options, callback)
                 // its list of remaining processes.
                 // (By default, `systemd-shutdown` waits 90 seconds
                 // for a root cgroup SIGCHLD that is never sent.)
-                killSig(vmobj.pid, 'SIGCHLD');
+                fs.readlink('/proc/' + vmobj.pid + '/path/a.out',
+                    function (err, link) {
+                        if (!err && jsprim.endsWith(link, '/systemd-shutdown')) {
+                            killSig(vmobj.pid, 'SIGCHLD');
+                        }
+                    });
 
                 if (Date.now(0) > stop_timeout) {
                     clearInterval(ival);
@@ -18235,7 +18240,12 @@ function doReboot(vmobj, options, callback)
               // its list of remaining processes.
               // (By default, `systemd-shutdown` waits 90 seconds
               // for a root cgroup SIGCHLD that is never sent.)
-              killSig(vmobj.pid, 'SIGCHLD');
+              fs.readlink('/proc/' + vmobj.pid + '/path/a.out',
+                  function (err, link) {
+                      if (!err && jsprim.endsWith(link, '/systemd-shutdown')) {
+                          killSig(vmobj.pid, 'SIGCHLD');
+                      }
+                  });
             }
             if (reboot_complete) {
                 log.debug('reboot marked complete, cleaning up');