Patch "ACPI / APEI: Add missing synchronize_rcu() on NOTIFY_SCI removal" has been added to the 3.18-stable tree

Patch "ACPI / APEI: Add missing synchronize_rcu() on NOTIFY_SCI removal" has been added to the 3.18-stable tree

[gregkh]

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

    ACPI / APEI: Add missing synchronize_rcu() on NOTIFY_SCI removal

to the 3.18-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:
     acpi-apei-add-missing-synchronize_rcu-on-notify_sci-removal.patch
and it can be found in the queue-3.18 subdirectory.

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


>From 7d64f82cceb21e6d95db312d284f5f195e120154 Mon Sep 17 00:00:00 2001
From: James Morse <james.morse@arm.com>
Date: Thu, 16 Mar 2017 14:30:39 +0000
Subject: ACPI / APEI: Add missing synchronize_rcu() on NOTIFY_SCI removal

From: James Morse <james.morse@arm.com>

commit 7d64f82cceb21e6d95db312d284f5f195e120154 upstream.

When removing a GHES device notified by SCI, list_del_rcu() is used,
ghes_remove() should call synchronize_rcu() before it goes on to call
kfree(ghes), otherwise concurrent RCU readers may still hold this list
entry after it has been freed.

Signed-off-by: James Morse <james.morse@arm.com>
Reviewed-by: "Huang, Ying" <ying.huang@intel.com>
Fixes: 81e88fdc432a (ACPI, APEI, Generic Hardware Error Source POLL/IRQ/NMI notification type support)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/acpi/apei/ghes.c |    1 +
 1 file changed, 1 insertion(+)

--- a/drivers/acpi/apei/ghes.c
+++ b/drivers/acpi/apei/ghes.c
@@ -1078,6 +1078,7 @@ static int ghes_remove(struct platform_d
 		if (list_empty(&ghes_sci))
 			unregister_acpi_hed_notifier(&ghes_notifier_sci);
 		mutex_unlock(&ghes_list_mutex);
+		synchronize_rcu();
 		break;
 	case ACPI_HEST_NOTIFY_NMI:
 		ghes_nmi_remove(ghes);


Patches currently in stable-queue which might be from james.morse@arm.com are

queue-3.18/acpi-apei-add-missing-synchronize_rcu-on-notify_sci-removal.patch