From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934516AbdKAV3q (ORCPT ); Wed, 1 Nov 2017 17:29:46 -0400 Received: from wtarreau.pck.nerim.net ([62.212.114.60]:35519 "EHLO 1wt.eu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933724AbdKAV3n (ORCPT ); Wed, 1 Nov 2017 17:29:43 -0400 From: Willy Tarreau To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, linux@roeck-us.net Cc: James Morse , "Rafael J . Wysocki" , Willy Tarreau Subject: [PATCH 3.10 123/139] ACPI / APEI: Add missing synchronize_rcu() on NOTIFY_SCI removal Date: Wed, 1 Nov 2017 22:26:48 +0100 Message-Id: <1509571624-5001-24-git-send-email-w@1wt.eu> X-Mailer: git-send-email 2.8.0.rc2.1.gbe9624a In-Reply-To: <1509571624-5001-1-git-send-email-w@1wt.eu> References: <1509571159-4405-1-git-send-email-w@1wt.eu> <1509571624-5001-1-git-send-email-w@1wt.eu> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: James Morse 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 Reviewed-by: "Huang, Ying" Fixes: 81e88fdc432a (ACPI, APEI, Generic Hardware Error Source POLL/IRQ/NMI notification type support) Signed-off-by: Rafael J. Wysocki Signed-off-by: Willy Tarreau --- drivers/acpi/apei/ghes.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c index 070b843..8cff7ca 100644 --- a/drivers/acpi/apei/ghes.c +++ b/drivers/acpi/apei/ghes.c @@ -988,6 +988,7 @@ static int ghes_remove(struct platform_device *ghes_dev) 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: mutex_lock(&ghes_list_mutex); -- 2.8.0.rc2.1.gbe9624a