4.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: James Morse <james.mo...@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.mo...@arm.com>
Reviewed-by: "Huang, Ying" <ying.hu...@intel.com>
Fixes: 81e88fdc432a (ACPI, APEI, Generic Hardware Error Source POLL/IRQ/NMI
notification type support)
Signed-off-by: Rafael J. Wysocki <rafael.j.wyso...@intel.com>
Signed-off-by: Greg Kroah-Hartman <gre...@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
@@ -1067,6 +1067,7 @@ 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);
