From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755150AbbI2GCt (ORCPT ); Tue, 29 Sep 2015 02:02:49 -0400 Received: from mga02.intel.com ([134.134.136.20]:31277 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751293AbbI2GCm (ORCPT ); Tue, 29 Sep 2015 02:02:42 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.17,606,1437462000"; d="scan'208";a="799383217" From: Jarkko Sakkinen To: tpmdd-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org Cc: akpm@linux-foundation.org, Jarkko Sakkinen , Peter Huewe , Marcel Selhorst , Jason Gunthorpe Subject: [PATCH] tpm, tpm_crb: fix unaligned read of the command buffer address Date: Tue, 29 Sep 2015 09:02:33 +0300 Message-Id: <1443506553-31224-1-git-send-email-jarkko.sakkinen@linux.intel.com> X-Mailer: git-send-email 2.5.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The command buffer address must be read with exactly two 32-bit reads. Otherwise, on Broxton platform HW will abort the read operation, which causes the CPU to fill the read with 1's. Therefore, we cannot rely on memcpy_fromio() but must call ioread32() two times instead. Also, this matches the PC Client Platform TPM Profile specification, which defines command buffer address with two 32-bit fields. Reported-by: Imran Desai Signed-off-by: Jarkko Sakkinen --- drivers/char/tpm/tpm_crb.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/drivers/char/tpm/tpm_crb.c b/drivers/char/tpm/tpm_crb.c index b4564b6..c09b370 100644 --- a/drivers/char/tpm/tpm_crb.c +++ b/drivers/char/tpm/tpm_crb.c @@ -68,7 +68,8 @@ struct crb_control_area { u32 int_enable; u32 int_sts; u32 cmd_size; - u64 cmd_pa; + u32 cmd_pa_low; + u32 cmd_pa_high; u32 rsp_size; u64 rsp_pa; } __packed; @@ -263,8 +264,8 @@ static int crb_acpi_add(struct acpi_device *device) return -ENOMEM; } - memcpy_fromio(&pa, &priv->cca->cmd_pa, 8); - pa = le64_to_cpu(pa); + pa = ((u64) le32_to_cpu(ioread32(&priv->cca->cmd_pa_high)) << 32) + + (u64) le32_to_cpu(ioread32(&priv->cca->cmd_pa_low)); priv->cmd = devm_ioremap_nocache(dev, pa, ioread32(&priv->cca->cmd_size)); if (!priv->cmd) { -- 2.5.0