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Blame SOURCES/0310-device-make-sure-to-not-ignore-re-plugged-device.patch

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From 45ff3d79f079c73c73209940cf6eaa0ea0a95708 Mon Sep 17 00:00:00 2001
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From: Franck Bui <fbui@suse.com>
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Date: Fri, 22 Jan 2016 07:18:19 +0100
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Subject: [PATCH] device: make sure to not ignore re-plugged device
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systemd automatically mounts device unless 'noauto' is part of the
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mount options. This can happen during boot if the device is plugged at
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that time or later when the system is already running (the latter case
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is not documented AFAICS).
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After the systemd booted, I plugged my USB device which had an entry
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in /etc/fstab with the default options and systemd automatically
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mounted it.
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However I noticed that if I unplugged and re-plugged the device the
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automatic mounting of the device didn't work anymore: systemd didn't
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notice that the device was re-plugged.
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This was due to the device unit which was not recycled by the GC
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during the unplug event because in the case of automounting, the mount
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unit still referenced it. When the device was re-plugged, the old
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device unit was reused but it still had the old sysfs path (amongst
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other useful information).
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Systemd was confused by the stalled sysfs path and decided to ignore
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the plug event.
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This patch fixes this issue by simply not doing the sanity checking on
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the sysfs path if the device is in unplugged state.
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Cherry-picked from: ac9d396b2abbae4e7ab84f7b556f70681b66236b
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Resolves: #1332606
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---
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 src/core/device.c | 18 +++++++++++++-----
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 1 file changed, 13 insertions(+), 5 deletions(-)
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diff --git a/src/core/device.c b/src/core/device.c
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index 1995e3c0b..fc73e263a 100644
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--- a/src/core/device.c
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+++ b/src/core/device.c
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@@ -314,11 +314,19 @@ static int device_setup_unit(Manager *m, struct udev_device *dev, const char *pa
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         u = manager_get_unit(m, e);
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-        if (u &&
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-            DEVICE(u)->sysfs &&
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-            !path_equal(DEVICE(u)->sysfs, sysfs)) {
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-                log_unit_debug(u->id, "Device %s appeared twice with different sysfs paths %s and %s", e, DEVICE(u)->sysfs, sysfs);
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-                return -EEXIST;
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+        /* The device unit can still be present even if the device was
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+         * unplugged: a mount unit can reference it hence preventing
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+         * the GC to have garbaged it. That's desired since the device
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+         * unit may have a dependency on the mount unit which was
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+         * added during the loading of the later. */
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+        if (u && DEVICE(u)->state == DEVICE_PLUGGED) {
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+                /* This unit is in plugged state: we're sure it's
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+                 * attached to a device. */
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+                if (!path_equal(DEVICE(u)->sysfs, sysfs)) {
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+                        log_unit_debug(u->id, "Dev %s appeared twice with different sysfs paths %s and %s",
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+                                       e, DEVICE(u)->sysfs, sysfs);
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+                        return -EEXIST;
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+                }
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         }
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         if (!u) {