From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter Hurley Subject: [PATCH 10/26] serial: core: Document lock requirement for UPF_* flags updates Date: Tue, 2 Sep 2014 17:39:19 -0400 Message-ID: <1409693975-1028-11-git-send-email-peter@hurleysoftware.com> References: <1409693975-1028-1-git-send-email-peter@hurleysoftware.com> Return-path: In-Reply-To: <1409693975-1028-1-git-send-email-peter@hurleysoftware.com> Sender: linux-kernel-owner@vger.kernel.org To: Greg Kroah-Hartman Cc: Jiri Slaby , One Thousand Gnomes , linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org, Peter Hurley List-Id: linux-serial@vger.kernel.org The flags field of struct uart_port can only be safely modified if the port mutex is held; no other lock prevents concurrent changes from corrupting the field. Signed-off-by: Peter Hurley --- include/linux/serial_core.h | 1 + 1 file changed, 1 insertion(+) diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h index 5bbb809..4a43292 100644 --- a/include/linux/serial_core.h +++ b/include/linux/serial_core.h @@ -152,6 +152,7 @@ struct uart_port { unsigned long sysrq; /* sysrq timeout */ #endif + /* flags must be updated while holding port mutex */ upf_t flags; #define UPF_FOURPORT ((__force upf_t) (1 << 1)) -- 2.1.0