From patchwork Wed Jan 22 11:39:26 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Denis Arefev X-Patchwork-Id: 859352 Received: from mx.swemel.ru (mx.swemel.ru [95.143.211.150]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7A18A211A2B; Wed, 22 Jan 2025 11:39:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.143.211.150 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1737545981; cv=none; b=OVH33wu+EzsjW9gg+tKWevVxD61mvcnSZPr+kOaZAzHfKMSLSdv2HHDIAavXePTnWte/hNDd4jvwbY5d42tix/UDLGzSr3hzrKbUSy9cOJa3cxzgvSPku0V9Z8CSA2wsfaGHe8cOtGo+piTcWn1p89mL17R6l5WFi4aK2KPFp0s= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1737545981; c=relaxed/simple; bh=+dVhSQUvLzcvSSYXfU/4UkSbcl4EP9qLyCUDk1YeA8I=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=M3ikXjh0sEnColZcUPn6ekQSzBoNz3BqBf4+YdealxCbyUruEERCiS/S5zumCxH5l1HQio97etlL2l9VQD5QlEY1e+BH1RA23mYTnr4IznIgQGlR+iIzh04fJ1NIivuVXwZVifj24eZysd8pI0Rbh3RlorRV/fOCONOlHO8Ob88= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=swemel.ru; spf=pass smtp.mailfrom=swemel.ru; dkim=pass (1024-bit key) header.d=swemel.ru header.i=@swemel.ru header.b=HmfKgzt8; arc=none smtp.client-ip=95.143.211.150 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=swemel.ru Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=swemel.ru Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=swemel.ru header.i=@swemel.ru header.b="HmfKgzt8" From: Denis Arefev DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=swemel.ru; s=mail; t=1737545967; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=uvXoMozXSUq7ECwRvOIW2A8tWpZ7jbIGzymPHm6Jvjg=; b=HmfKgzt8BUKnKCByrmvAc7jYejozQtTKXhFPQO2ZlaDjE7uqLoeulo4MU1o6x/B6pG0CUS iLq8RCru4oNQnLHQ1cGUDLn3n/l6wkTF2itevxnVifj6jgvyEnrF9PwiLvYWP2NsJWAJpW lxFrZti5R9Fa4NOmuXh1UQE7g+ma0cs= To: stable@vger.kernel.org, Greg Kroah-Hartman Cc: Jiri Slaby , Shawn Guo , Sascha Hauer , Pengutronix Kernel Team , Fabio Estevam , NXP Linux Team , linux-serial@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, lvc-project@linuxtesting.org, Esben Haabendal , Marc Kleine-Budde Subject: [PATCH 5.10] serial: imx: Introduce timeout when waiting on transmitter empty Date: Wed, 22 Jan 2025 14:39:26 +0300 Message-ID: <20250122113927.301596-1-arefev@swemel.ru> Precedence: bulk X-Mailing-List: linux-serial@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Esben Haabendal commit e533e4c62e9993e62e947ae9bbec34e4c7ae81c2 upstream. By waiting at most 1 second for USR2_TXDC to be set, we avoid a potential deadlock. In case of the timeout, there is not much we can do, so we simply ignore the transmitter state and optimistically try to continue. Signed-off-by: Esben Haabendal Acked-by: Marc Kleine-Budde Link: https://lore.kernel.org/r/919647898c337a46604edcabaf13d42d80c0915d.1712837613.git.esben@geanix.com Signed-off-by: Greg Kroah-Hartman [Denis: minor fix to resolve merge conflict.] Signed-off-by: Denis Arefev --- Backport fix for CVE-2024-40967 Link: https://nvd.nist.gov/vuln/detail/CVE-2024-40967 --- drivers/tty/serial/imx.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c index 6e49928bb864..5abf6685fe3c 100644 --- a/drivers/tty/serial/imx.c +++ b/drivers/tty/serial/imx.c @@ -27,6 +27,7 @@ #include #include #include +#include #include #include @@ -2006,8 +2007,8 @@ imx_uart_console_write(struct console *co, const char *s, unsigned int count) { struct imx_port *sport = imx_uart_ports[co->index]; struct imx_port_ucrs old_ucr; - unsigned int ucr1; - unsigned long flags = 0; + unsigned long flags; + unsigned int ucr1, usr2; int locked = 1; if (sport->port.sysrq) @@ -2038,8 +2039,8 @@ imx_uart_console_write(struct console *co, const char *s, unsigned int count) * Finally, wait for transmitter to become empty * and restore UCR1/2/3 */ - while (!(imx_uart_readl(sport, USR2) & USR2_TXDC)); - + read_poll_timeout_atomic(imx_uart_readl, usr2, usr2 & USR2_TXDC, + 0, USEC_PER_SEC, false, sport, USR2); imx_uart_ucrs_restore(sport, &old_ucr); if (locked)