ACK: [PATCH] bios: smm: add a test to check SMM lock bits

[ivanhu]

On 3/9/21 1:06 PM, Alex Hung wrote:
> Signed-off-by: Alex Hung <alex.hung at canonical.com>
> ---
>  src/Makefile.am    |   1 +
>  src/bios/smm/smm.c | 115 +++++++++++++++++++++++++++++++++++++++++++++
>  2 files changed, 116 insertions(+)
>  create mode 100644 src/bios/smm/smm.c
> 
> diff --git a/src/Makefile.am b/src/Makefile.am
> index b7f3f7db..b447e357 100644
> --- a/src/Makefile.am
> +++ b/src/Makefile.am
> @@ -162,6 +162,7 @@ fwts_SOURCES = main.c 				\
>  	bios/pnp/pnp.c 				\
>  	bios/romdump/romdump.c 			\
>  	bios/s0idle/s0idle.c 			\
> +	bios/smm/smm.c				\
>  	cmos/cmosdump/cmosdump.c 		\
>  	coreboot/clog/clog.c			\
>  	cpu/virt/virt.c 			\
> diff --git a/src/bios/smm/smm.c b/src/bios/smm/smm.c
> new file mode 100644
> index 00000000..990c7bd4
> --- /dev/null
> +++ b/src/bios/smm/smm.c
> @@ -0,0 +1,115 @@
> +/*
> + * Copyright (C) 2021 Canonical
> + *
> + * This code was originally part of the Linux-ready Firmware Developer Kit
> + *
> + * This program is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU General Public License
> + * as published by the Free Software Foundation; either version 2
> + * of the License, or (at your option) any later version.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program; if not, write to the Free Software
> + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
> + *
> + */
> +#include "fwts.h"
> +
> +#ifdef FWTS_ARCH_INTEL
> +
> +#include <stdlib.h>
> +#include <stdio.h>
> +#include <fcntl.h>
> +
> +#define FWTS_INTEL_HOST_PATH	"/sys/bus/pci/devices/0000:00:00.0/config"
> +
> +#define FWTS_GGC			0x50
> +#define FWTS_TSEGMB		0xB8
> +#define FWTS_TOLUD		0xBC
> +#define FWTS_LOCK_FIELD	0x01
> +
> +static int smm_init(fwts_framework *fw)
> +{
> +	bool intel;
> +
> +	if (fwts_cpu_is_Intel(&intel) != FWTS_OK) {
> +		fwts_log_error(fw, "Cannot determine processor type.");
> +		return FWTS_ERROR;
> +	}
> +
> +	if (!intel) {
> +		fwts_log_info(fw, "The SMM test currently only supports Intel platforms.");
> +		return FWTS_SKIP;
> +	}
> +
> +	return FWTS_OK;
> +}
> +
> +static int smm_deinit(fwts_framework *fw)
> +{
> +	FWTS_UNUSED(fw);
> +	return FWTS_OK;
> +}
> +
> +static int smm_test0(fwts_framework *fw)
> +{
> +	uint8_t config[256];
> +	bool passed = true;
> +	ssize_t n;
> +	int fd;
> +
> +	if ((fd = open(FWTS_INTEL_HOST_PATH, O_RDONLY)) < 0) {
> +		fwts_log_warning(fw, "Could not open PCI HOST bridge config data\n");
> +		return FWTS_ERROR;
> +	}
> +	if ((n = read(fd, config, sizeof(config))) < 0) {
> +		fwts_log_warning(fw, "Could not read PCI HOST bridge config data\n");
> +		(void)close(fd);
> +		return FWTS_ERROR;
> +	}
> +	(void)close(fd);
> +
> +	if ((config[FWTS_GGC] & FWTS_LOCK_FIELD) != 1) {
> +		fwts_failed(fw, LOG_LEVEL_HIGH, "SMMGGCNotLocked",
> +			"Graphics Control register is not locked (GGCLCK != 1).");
> +		passed = false;
> +	}
> +
> +	if ((config[FWTS_TSEGMB] & FWTS_LOCK_FIELD) != 1) {
> +		fwts_failed(fw, LOG_LEVEL_HIGH, "SMMTSEGNotLocked",
> +			"TSEG Memory Base register is not locked.");
> +		passed = false;
> +	}
> +
> +	if ((config[FWTS_TOLUD] & FWTS_LOCK_FIELD) != 1) {
> +		fwts_failed(fw, LOG_LEVEL_HIGH, "SMMTOLUDNotLocked",
> +			"Top of Low Usable DRAM (TOLUD) register is not locked.");
> +		passed = false;
> +	}
> +
> +	if (passed)
> +		fwts_passed(fw, "No issues found in SMM locks.");
> +
> +	return FWTS_OK;
> +}
> +
> +static fwts_framework_minor_test smm_tests[] = {
> +	{ smm_test0, "Validate the System management mode (SMM) locks." },
> +	{ NULL, NULL }
> +};
> +
> +static fwts_framework_ops smm_ops = {
> +	.description = "SMM tests.",
> +	.init        = smm_init,
> +	.deinit      = smm_deinit,
> +	.minor_tests = smm_tests
> +};
> +
> +FWTS_REGISTER("smm", &smm_ops, FWTS_TEST_ANYTIME, FWTS_FLAG_BATCH | FWTS_FLAG_ROOT_PRIV)
> +
> +#endif
> 

Acked-by: Ivan Hu <ivan.hu at canonical.com>