From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:37738 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751451AbdCXPD5 (ORCPT ); Fri, 24 Mar 2017 11:03:57 -0400 Subject: Patch "hwrng: omap - write registers after enabling the clock" has been added to the 4.10-stable tree To: thomas.petazzoni@free-electrons.com, gregkh@linuxfoundation.org, herbert@gondor.apana.org.au Cc: , From: Date: Fri, 24 Mar 2017 16:02:05 +0100 Message-ID: <1490367725396@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled hwrng: omap - write registers after enabling the clock to the 4.10-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: hwrng-omap-write-registers-after-enabling-the-clock.patch and it can be found in the queue-4.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From 45c2fdde01299b02a6e3225e848598a3c1e55539 Mon Sep 17 00:00:00 2001 From: Thomas Petazzoni Date: Tue, 7 Mar 2017 15:14:46 +0100 Subject: hwrng: omap - write registers after enabling the clock From: Thomas Petazzoni commit 45c2fdde01299b02a6e3225e848598a3c1e55539 upstream. Commit 383212425c926 ("hwrng: omap - Add device variant for SafeXcel IP-76 found in Armada 8K") added support for the SafeXcel IP-76 variant of the IP. This modification included getting a reference and enabling a clock. Unfortunately, this was done *after* writing to the RNG_INTMASK_REG register. This generally works fine when the driver is built-in because the clock might have been left enabled by the bootloader, but fails short when the driver is built as a module: it causes a system hang because a register is being accessed while the clock is not enabled. This commit fixes that by making the register access *after* enabling the clock. This issue was found by the kernelci.org testing effort. Fixes: 383212425c926 ("hwrng: omap - Add device variant for SafeXcel IP-76 found in Armada 8K") Signed-off-by: Thomas Petazzoni Signed-off-by: Herbert Xu Signed-off-by: Greg Kroah-Hartman --- drivers/char/hw_random/omap-rng.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/drivers/char/hw_random/omap-rng.c +++ b/drivers/char/hw_random/omap-rng.c @@ -397,7 +397,6 @@ static int of_get_omap_rng_device_detail irq, err); return err; } - omap_rng_write(priv, RNG_INTMASK_REG, RNG_SHUTDOWN_OFLO_MASK); priv->clk = of_clk_get(pdev->dev.of_node, 0); if (IS_ERR(priv->clk) && PTR_ERR(priv->clk) == -EPROBE_DEFER) @@ -408,6 +407,8 @@ static int of_get_omap_rng_device_detail dev_err(&pdev->dev, "unable to enable the clk, " "err = %d\n", err); } + + omap_rng_write(priv, RNG_INTMASK_REG, RNG_SHUTDOWN_OFLO_MASK); } return 0; } Patches currently in stable-queue which might be from thomas.petazzoni@free-electrons.com are queue-4.10/hwrng-omap-use-devm_clk_get-instead-of-of_clk_get.patch queue-4.10/hwrng-omap-do-not-access-intmask_reg-on-eip76.patch queue-4.10/hwrng-omap-write-registers-after-enabling-the-clock.patch