Patch "devcoredump: Send uevent once devcd is ready" has been added to the 4.19-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    devcoredump: Send uevent once devcd is ready

to the 4.19-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     devcoredump-send-uevent-once-devcd-is-ready.patch
and it can be found in the queue-4.19 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit 5829bd2d0869d252dea2f9712d317f30f4655c7a
Author: Mukesh Ojha <quic_mojha@xxxxxxxxxxx>
Date:   Fri Nov 17 20:19:32 2023 +0530

    devcoredump: Send uevent once devcd is ready
    
    [ Upstream commit af54d778a03853801d681c98c0c2a6c316ef9ca7 ]
    
    dev_coredumpm() creates a devcoredump device and adds it
    to the core kernel framework which eventually end up
    sending uevent to the user space and later creates a
    symbolic link to the failed device. An application
    running in userspace may be interested in this symbolic
    link to get the name of the failed device.
    
    In a issue scenario, once uevent sent to the user space
    it start reading '/sys/class/devcoredump/devcdX/failing_device'
    to get the actual name of the device which might not been
    created and it is in its path of creation.
    
    To fix this, suppress sending uevent till the failing device
    symbolic link gets created and send uevent once symbolic
    link is created successfully.
    
    Fixes: 833c95456a70 ("device coredump: add new device coredump class")
    Signed-off-by: Mukesh Ojha <quic_mojha@xxxxxxxxxxx>
    Cc: stable@xxxxxxxxxxxxxxx
    Link: https://lore.kernel.org/r/1700232572-25823-1-git-send-email-quic_mojha@xxxxxxxxxxx
    Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/drivers/base/devcoredump.c b/drivers/base/devcoredump.c
index 1ba4af7f2f21f..b13574cdef69b 100644
--- a/drivers/base/devcoredump.c
+++ b/drivers/base/devcoredump.c
@@ -376,6 +376,7 @@ void dev_coredumpm(struct device *dev, struct module *owner,
 	devcd->devcd_dev.class = &devcd_class;
 
 	mutex_lock(&devcd->mutex);
+	dev_set_uevent_suppress(&devcd->devcd_dev, true);
 	if (device_add(&devcd->devcd_dev))
 		goto put_device;
 
@@ -387,6 +388,8 @@ void dev_coredumpm(struct device *dev, struct module *owner,
 			      "devcoredump"))
 		/* nothing - symlink will be missing */;
 
+	dev_set_uevent_suppress(&devcd->devcd_dev, false);
+	kobject_uevent(&devcd->devcd_dev.kobj, KOBJ_ADD);
 	INIT_DELAYED_WORK(&devcd->del_wk, devcd_del);
 	schedule_delayed_work(&devcd->del_wk, DEVCD_TIMEOUT);
 	mutex_unlock(&devcd->mutex);