From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793211286; b=DZSltddUhOsv/pE1KtuEGDPXhUHE2kKDXAKY0J3TQ+cNhOVsED/Mq32ZeuxePlB99L8W aLEQl7ZEMT8BzHpqYoWXaBr+dw8MaaoKoqaWpRvQmYb/oZep+kOFUap0LNYjlLvGYqvW9 RdZTNJNg0n9Ra6pkQR9Hi7G4SNjeJBTXQ85NomHX6JiS6pHA9JK8ukBHvEItPQdlBfMvY 8RlToXxltZtbGKn8Bl1fChDWtkrntgDREGeFJEm1VQzImtWSkGggiJ2/4oldOxqCpFQ4k cRZ/QKLbi1BaZHZr+k56joeNDqeO4fSwrcYg8hGqBVOhMVS1ysPNzVKAIFzufwbzsjA== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793211286; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:User-Agent:X-stable:X-Patchwork-Hint: MIME-Version:Content-Transfer-Encoding; bh=PyciHQ91MACIJ/us+17kvAem3u4E8SErn1Zmj1Gn8iI=; b=iRXFMTK/sQ8qQ6IgLy4FdJGBhyZzNiJA+qNEE7gV5QmUC0yflYD0E1Ssm9hhwlQQ9Non TwviKVmwX2gH9eYgjRnJEzmog7h2zLhsusb0u+5sH898knJY6KFTBD/9Fgr/YXyLvjALH U4z21AJJcKFcuAWER07VCWW4guFAXRYap2SV+4cS83zfTW0kxQGyAqFlsaXUblXxAfhOb ZG5/MI6PWzeDYUcklhYpLLHvwI4NrBLzHti3DoLsIwML09+hngnq+vyqOKYWW+It6p6Hk 3b0rXy2WUB+aoHF7qyqEQPAijb4co6SbkirIKevKkOYAzuexQAORSFaIcuHcb6qIyjw== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=es0BxFsE; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D258960A2621; Wed, 28 Oct 2026 18:14:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=es0BxFsE Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2C8B01F01829; Wed, 28 Oct 2026 18:14:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1793211285; bh=PyciHQ91MACIJ/us+17kvAem3u4E8SErn1Zmj1Gn8iI=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=es0BxFsEvYWYEMxir3+Frfc1JIsNVpBki7trK27erisFutKyc8DMT/w4SNwoeV2i8 4hE/5wY2upiSOxmWIZl3rTInR+MehZRTnIILu1qNoRosT1YbD591D9HKtd/eJrj4mU rRgMDwrhcLkFXkPSU4KUfVf3lL/B2WGxd4/PQKCE= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, sashiko-bot@kernel.org, stable@kernel.org, Johan Hovold , Sasha Levin Subject: [PATCH 5.15 317/571] serial: fix TIOCMIWAIT race Date: Wed, 28 Oct 2026 17:57:44 +0100 Message-ID: <20261028170015.521698285@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261028170008.009143722@linuxfoundation.org> References: <20261028170008.009143722@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore X-Mailing-List: patches@lists.linux.dev List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Johan Hovold [ Upstream commit 40adffec8c0090533dfaa863ced7901b60bbf1dc ] The task state must be updated before checking the wakeup condition to avoid missing a racing modem status update. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: sashiko-bot@kernel.org Link: https://lore.kernel.org/r/20260904115542.E20D11F00A3D@smtp.kernel.org Cc: stable@kernel.org Signed-off-by: Johan Hovold Link: https://patch.msgid.link/20260910130816.642699-4-johan@kernel.org Signed-off-by: Greg Kroah-Hartman [ sashal: Adjusted context for direct spin_lock_irq() and spin_unlock_irq() calls. ] Signed-off-by: Sasha Levin --- drivers/tty/serial/serial_core.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c index 404354727d194..1cba822e068e9 100644 --- a/drivers/tty/serial/serial_core.c +++ b/drivers/tty/serial/serial_core.c @@ -1213,12 +1213,12 @@ static int uart_wait_modem_status(struct uart_state *state, unsigned long arg) add_wait_queue(&port->delta_msr_wait, &wait); for (;;) { + set_current_state(TASK_INTERRUPTIBLE); + spin_lock_irq(&uport->lock); memcpy(&cnow, &uport->icount, sizeof(struct uart_icount)); spin_unlock_irq(&uport->lock); - set_current_state(TASK_INTERRUPTIBLE); - if (((arg & TIOCM_RNG) && (cnow.rng != cprev.rng)) || ((arg & TIOCM_DSR) && (cnow.dsr != cprev.dsr)) || ((arg & TIOCM_CD) && (cnow.dcd != cprev.dcd)) || -- 2.53.0