From a0767672aac01f41516550e3808ff72da893102f Mon Sep 17 00:00:00 2001
From: Georgy Yakovlev <gyakovlev@gentoo.org>
Date: Tue, 26 Nov 2019 12:07:36 -0800
Subject: [PATCH] backport udev timeout patch

https://github.com/zfsonlinux/zfs/commit/803884217f9b9b5fb235d7c5e78a809d271f6387
---
 lib/libzfs/libzfs_import.c | 11 ++++++++++-
 man/man8/zpool.8           |  6 ++++++
 2 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/lib/libzfs/libzfs_import.c b/lib/libzfs/libzfs_import.c
index 9dbf207..cd08806 100644
--- a/lib/libzfs/libzfs_import.c
+++ b/lib/libzfs/libzfs_import.c
@@ -53,6 +53,7 @@
 #endif
 #include <stddef.h>
 #include <stdlib.h>
+#include <stdio.h>
 #include <string.h>
 #include <sys/stat.h>
 #include <unistd.h>
@@ -1594,17 +1595,25 @@ zpool_open_func(void *arg)
 	if (rn->rn_labelpaths) {
 		char *path = NULL;
 		char *devid = NULL;
+		char *env = NULL;
 		rdsk_node_t *slice;
 		avl_index_t where;
+		int timeout;
 		int error;
 
 		if (label_paths(rn->rn_hdl, rn->rn_config, &path, &devid))
 			return;
 
+		env = getenv("ZPOOL_IMPORT_UDEV_TIMEOUT_MS");
+		if ((env == NULL) || sscanf(env, "%d", &timeout) != 1 ||
+		    timeout < 0) {
+			timeout = DISK_LABEL_WAIT;
+		}
+
 		/*
 		 * Allow devlinks to stabilize so all paths are available.
 		 */
-		zpool_label_disk_wait(rn->rn_name, DISK_LABEL_WAIT);
+		zpool_label_disk_wait(rn->rn_name, timeout);
 
 		if (path != NULL) {
 			slice = zfs_alloc(hdl, sizeof (rdsk_node_t));
diff --git a/man/man8/zpool.8 b/man/man8/zpool.8
index 46e531e..10a19b5 100644
--- a/man/man8/zpool.8
+++ b/man/man8/zpool.8
@@ -2291,6 +2291,12 @@ Similar to the
 option in
 .Nm zpool import .
 .El
+.Bl -tag -width "ZPOOL_IMPORT_UDEV_TIMEOUT_MS"
+.It Ev ZPOOL_IMPORT_UDEV_TIMEOUT_MS
+The maximum time in milliseconds that
+.Nm zpool import
+will wait for an expected device to be available.
+.El
 .Bl -tag -width "ZPOOL_VDEV_NAME_GUID"
 .It Ev ZPOOL_VDEV_NAME_GUID
 Cause
-- 
2.24.0