From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 41C2011C86 for ; Thu, 24 Aug 2023 14:57:31 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B4E11C433C8; Thu, 24 Aug 2023 14:57:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1692889051; bh=kn5U04wt/x+mdGTzL3UCnk/p0FmMVh3g1zG1KIj1CBY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=oVuCBrxgNQuC2xfWs/EoShhcWENGbQtKqkAtDpVIvUME9YTg09OgVjT5yTDQecoQG WokuhWwmHigtIl+QcgEts34u6bqfXeVJ6dxasmz+72Mc+s6asKYbFaVyuFacLihwoo PXN7QTfnFE9YCSrMpoujTDnKAqsJNwJGijWiLG+s= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Tony Lindgren , Sasha Levin Subject: [PATCH 5.15 109/139] serial: 8250: Fix oops for port->pm on uart_change_pm() Date: Thu, 24 Aug 2023 16:50:32 +0200 Message-ID: <20230824145028.259796631@linuxfoundation.org> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20230824145023.559380953@linuxfoundation.org> References: <20230824145023.559380953@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Tony Lindgren [ Upstream commit dfe2aeb226fd5e19b0ee795f4f6ed8bc494c1534 ] Unloading a hardware specific 8250 driver can produce error "Unable to handle kernel paging request at virtual address" about ten seconds after unloading the driver. This happens on uart_hangup() calling uart_change_pm(). Turns out commit 04e82793f068 ("serial: 8250: Reinit port->pm on port specific driver unbind") was only a partial fix. If the hardware specific driver has initialized port->pm function, we need to clear port->pm too. Just reinitializing port->ops does not do this. Otherwise serial8250_pm() will call port->pm() instead of serial8250_do_pm(). Fixes: 04e82793f068 ("serial: 8250: Reinit port->pm on port specific driver unbind") Signed-off-by: Tony Lindgren Link: https://lore.kernel.org/r/20230804131553.52927-1-tony@atomide.com Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- drivers/tty/serial/8250/8250_port.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c index ad5b742a68cd0..74e477016f255 100644 --- a/drivers/tty/serial/8250/8250_port.c +++ b/drivers/tty/serial/8250/8250_port.c @@ -3274,6 +3274,7 @@ void serial8250_init_port(struct uart_8250_port *up) struct uart_port *port = &up->port; spin_lock_init(&port->lock); + port->pm = NULL; port->ops = &serial8250_pops; port->has_sysrq = IS_ENABLED(CONFIG_SERIAL_8250_CONSOLE); -- 2.40.1