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 E8B9A1170E for ; Mon, 11 Sep 2023 13:51:56 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6BFB6C433C7; Mon, 11 Sep 2023 13:51:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1694440316; bh=qA6p7SCgUmuzsOXpkMM6nmu/aGCPjOUNdgd0qHIUXYs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=xZfoCA5eiMXKQ0B9dQLQMlkeQeOHpI16v3r8zv61q7KVtq0n+wDFxLKyTZmj902lp 0PiXHQEwdoMn8MJ55szxgIxorCtPI+VcJH+qXkdTb+BFd7wwibDFyEAGD3pIICHVmk 7iud1us8f3AVBoLm143HWBwm3+Zj4dnuLW26aV9I= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Todd Brandt , Patrick Steinhardt , Raymond Jay Golo , Ronan Pigott , Jerry Snitselaar , Jarkko Sakkinen , Thorsten Leemhuis Subject: [PATCH 6.5 003/739] tpm: Enable hwrng only for Pluton on AMD CPUs Date: Mon, 11 Sep 2023 15:36:42 +0200 Message-ID: <20230911134651.046403743@linuxfoundation.org> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20230911134650.921299741@linuxfoundation.org> References: <20230911134650.921299741@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.5-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jarkko Sakkinen commit 8f7f35e5aa6f2182eabcfa3abef4d898a48e9aa8 upstream. The vendor check introduced by commit 554b841d4703 ("tpm: Disable RNG for all AMD fTPMs") doesn't work properly on a number of Intel fTPMs. On the reported systems the TPM doesn't reply at bootup and returns back the command code. This makes the TPM fail probe on Lenovo Legion Y540 laptop. Since only Microsoft Pluton is the only known combination of AMD CPU and fTPM from other vendor, disable hwrng otherwise. In order to make sysadmin aware of this, print also info message to the klog. Cc: stable@vger.kernel.org Fixes: 554b841d4703 ("tpm: Disable RNG for all AMD fTPMs") Reported-by: Todd Brandt Closes: https://bugzilla.kernel.org/show_bug.cgi?id=217804 Reported-by: Patrick Steinhardt Reported-by: Raymond Jay Golo Reported-by: Ronan Pigott Reviewed-by: Jerry Snitselaar Signed-off-by: Jarkko Sakkinen Cc: Thorsten Leemhuis Signed-off-by: Greg Kroah-Hartman --- drivers/char/tpm/tpm_crb.c | 33 ++++++++------------------------- 1 file changed, 8 insertions(+), 25 deletions(-) --- a/drivers/char/tpm/tpm_crb.c +++ b/drivers/char/tpm/tpm_crb.c @@ -463,28 +463,6 @@ static bool crb_req_canceled(struct tpm_ return (cancel & CRB_CANCEL_INVOKE) == CRB_CANCEL_INVOKE; } -static int crb_check_flags(struct tpm_chip *chip) -{ - u32 val; - int ret; - - ret = crb_request_locality(chip, 0); - if (ret) - return ret; - - ret = tpm2_get_tpm_pt(chip, TPM2_PT_MANUFACTURER, &val, NULL); - if (ret) - goto release; - - if (val == 0x414D4400U /* AMD */) - chip->flags |= TPM_CHIP_FLAG_HWRNG_DISABLED; - -release: - crb_relinquish_locality(chip, 0); - - return ret; -} - static const struct tpm_class_ops tpm_crb = { .flags = TPM_OPS_AUTO_STARTUP, .status = crb_status, @@ -826,9 +804,14 @@ static int crb_acpi_add(struct acpi_devi if (rc) goto out; - rc = crb_check_flags(chip); - if (rc) - goto out; +#ifdef CONFIG_X86 + /* A quirk for https://www.amd.com/en/support/kb/faq/pa-410 */ + if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD && + priv->sm != ACPI_TPM2_COMMAND_BUFFER_WITH_PLUTON) { + dev_info(dev, "Disabling hwrng\n"); + chip->flags |= TPM_CHIP_FLAG_HWRNG_DISABLED; + } +#endif /* CONFIG_X86 */ rc = tpm_chip_register(chip);