tpm: Add reserved memory event log

  Some platforms may desire to pass the event log up to linux in the
form of a reserved memory region. Add support for this in the TPM
core to find the reserved memory region and map it.

Signed-off-by: Eddie James <eajames@linux.ibm.com>
---
 drivers/char/tpm/eventlog/of.c | 38 +++++++++++++++++++++++++++++++++-
 drivers/char/tpm/tpm-chip.c    |  3 ++-
 include/linux/tpm.h            |  1 +
 3 files changed, 40 insertions(+), 2 deletions(-)
  

Hi Eddie,

I love your patch! Perhaps something to improve:

[auto build test WARNING on char-misc/char-misc-testing]
[also build test WARNING on char-misc/char-misc-next char-misc/char-misc-linus linus/master v6.2-rc2 next-20221226]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Eddie-James/tpm-Add-reserved-memory-event-log/20230104-002229
patch link:    https://lore.kernel.org/r/20230103162010.381214-1-eajames%40linux.ibm.com
patch subject: [PATCH] tpm: Add reserved memory event log
config: arm-buildonly-randconfig-r005-20230101
compiler: clang version 16.0.0 (https://github.com/llvm/llvm-project 7a8cb6cd4e3ff8aaadebff2b9d3ee9e2a326d444)
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # install arm cross compiling tool for clang build
        # apt-get install binutils-arm-linux-gnueabi
        # https://github.com/intel-lab-lkp/linux/commit/6aebeea318ade8b695dc36f4c5a2ad166ae4f1a7
        git remote add linux-review https://github.com/intel-lab-lkp/linux
        git fetch --no-tags linux-review Eddie-James/tpm-Add-reserved-memory-event-log/20230104-002229
        git checkout 6aebeea318ade8b695dc36f4c5a2ad166ae4f1a7
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=arm olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=arm SHELL=/bin/bash drivers/char/tpm/

If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@intel.com>

All warnings (new ones prefixed by >>):

   In file included from drivers/char/tpm/tpm-chip.c:24:
   include/linux/tpm_eventlog.h:167:6: warning: variable 'mapping_size' set but not used [-Wunused-but-set-variable]
           int mapping_size;
               ^
>> drivers/char/tpm/tpm-chip.c:327:22: warning: cast from 'void (*)(const void *)' to 'void (*)(void *)' converts to incompatible function type [-Wcast-function-type-strict]
           chip->log.release = (void(*)(void *))kfree;
                               ^~~~~~~~~~~~~~~~~~~~~~
   2 warnings generated.


vim +327 drivers/char/tpm/tpm-chip.c

   302	
   303	/**
   304	 * tpm_chip_alloc() - allocate a new struct tpm_chip instance
   305	 * @pdev: device to which the chip is associated
   306	 *        At this point pdev mst be initialized, but does not have to
   307	 *        be registered
   308	 * @ops: struct tpm_class_ops instance
   309	 *
   310	 * Allocates a new struct tpm_chip instance and assigns a free
   311	 * device number for it. Must be paired with put_device(&chip->dev).
   312	 */
   313	struct tpm_chip *tpm_chip_alloc(struct device *pdev,
   314					const struct tpm_class_ops *ops)
   315	{
   316		struct tpm_chip *chip;
   317		int rc;
   318	
   319		chip = kzalloc(sizeof(*chip), GFP_KERNEL);
   320		if (chip == NULL)
   321			return ERR_PTR(-ENOMEM);
   322	
   323		mutex_init(&chip->tpm_mutex);
   324		init_rwsem(&chip->ops_sem);
   325	
   326		chip->ops = ops;
 > 327		chip->log.release = (void(*)(void *))kfree;
   328	
   329		mutex_lock(&idr_lock);
   330		rc = idr_alloc(&dev_nums_idr, NULL, 0, TPM_NUM_DEVICES, GFP_KERNEL);
   331		mutex_unlock(&idr_lock);
   332		if (rc < 0) {
   333			dev_err(pdev, "No available tpm device numbers\n");
   334			kfree(chip);
   335			return ERR_PTR(rc);
   336		}
   337		chip->dev_num = rc;
   338	
   339		device_initialize(&chip->dev);
   340	
   341		chip->dev.class = tpm_class;
   342		chip->dev.class->shutdown_pre = tpm_class_shutdown;
   343		chip->dev.release = tpm_dev_release;
   344		chip->dev.parent = pdev;
   345		chip->dev.groups = chip->groups;
   346	
   347		if (chip->dev_num == 0)
   348			chip->dev.devt = MKDEV(MISC_MAJOR, TPM_MINOR);
   349		else
   350			chip->dev.devt = MKDEV(MAJOR(tpm_devt), chip->dev_num);
   351	
   352		rc = dev_set_name(&chip->dev, "tpm%d", chip->dev_num);
   353		if (rc)
   354			goto out;
   355	
   356		if (!pdev)
   357			chip->flags |= TPM_CHIP_FLAG_VIRTUAL;
   358	
   359		cdev_init(&chip->cdev, &tpm_fops);
   360		chip->cdev.owner = THIS_MODULE;
   361	
   362		rc = tpm2_init_space(&chip->work_space, TPM2_SPACE_BUFFER_SIZE);
   363		if (rc) {
   364			rc = -ENOMEM;
   365			goto out;
   366		}
   367	
   368		chip->locality = -1;
   369		return chip;
   370	
   371	out:
   372		put_device(&chip->dev);
   373		return ERR_PTR(rc);
   374	}
   375	EXPORT_SYMBOL_GPL(tpm_chip_alloc);
   376
  

On Tue, Jan 03, 2023 at 10:20:10AM -0600, Eddie James wrote:
> Some platforms may desire to pass the event log up to linux in the
> form of a reserved memory region. Add support for this in the TPM
> core to find the reserved memory region and map it.
> 
> Signed-off-by: Eddie James <eajames@linux.ibm.com>

Which platforms? 

I do not see information of 

+	void (*release)(void *ptr);

in the commit message. The description of the implemenation approach is
missing.


> ---
>  drivers/char/tpm/eventlog/of.c | 38 +++++++++++++++++++++++++++++++++-
>  drivers/char/tpm/tpm-chip.c    |  3 ++-
>  include/linux/tpm.h            |  1 +
>  3 files changed, 40 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/char/tpm/eventlog/of.c b/drivers/char/tpm/eventlog/of.c
> index a9ce66d09a75..0455d7f61c10 100644
> --- a/drivers/char/tpm/eventlog/of.c
> +++ b/drivers/char/tpm/eventlog/of.c
> @@ -11,12 +11,48 @@
>   */
>  
>  #include <linux/slab.h>
> +#include <linux/io.h>
> +#include <linux/ioport.h>
>  #include <linux/of.h>
> +#include <linux/of_address.h>
> +#include <linux/of_reserved_mem.h>
>  #include <linux/tpm_eventlog.h>
>  
>  #include "../tpm.h"
>  #include "common.h"
>  
> +static int tpm_read_log_memory_region(struct tpm_chip *chip)
> +{
> +	struct device_node *node;
> +	struct resource res;
> +	int rc;
> +
> +	node = of_parse_phandle(chip->dev.parent->of_node, "memory-region", 0);
> +	if (!node) {
> +		dev_info(&chip->dev, "no phandle\n");
> +		return -ENODEV;
> +	}
> +
> +	rc = of_address_to_resource(node, 0, &res);
> +	of_node_put(node);
> +	if (rc) {
> +		dev_info(&chip->dev, "no mem\n");
> +		return rc;
> +	}
> +
> +	chip->log.bios_event_log = memremap(res.start, resource_size(&res), MEMREMAP_WB);
> +	if (!chip->log.bios_event_log) {
> +		dev_info(&chip->dev, "err memremap\n");
> +		return -ENOMEM;
> +	}
> +
> +	chip->log.release = memunmap;
> +	chip->log.bios_event_log_end = chip->log.bios_event_log + resource_size(&res);
> +
> +	return chip->flags & TPM_CHIP_FLAG_TPM2 ? EFI_TCG2_EVENT_LOG_FORMAT_TCG_2 :
> +		EFI_TCG2_EVENT_LOG_FORMAT_TCG_1_2;
> +}

We do not want to support TPM 1.2 for new features.

> +
>  int tpm_read_log_of(struct tpm_chip *chip)
>  {
>  	struct device_node *np;
> @@ -38,7 +74,7 @@ int tpm_read_log_of(struct tpm_chip *chip)
>  	sizep = of_get_property(np, "linux,sml-size", NULL);
>  	basep = of_get_property(np, "linux,sml-base", NULL);
>  	if (sizep == NULL && basep == NULL)
> -		return -ENODEV;
> +		return tpm_read_log_memory_region(chip);
>  	if (sizep == NULL || basep == NULL)
>  		return -EIO;
>  
> diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c
> index 741d8f3e8fb3..09ea8145d7c6 100644
> --- a/drivers/char/tpm/tpm-chip.c
> +++ b/drivers/char/tpm/tpm-chip.c
> @@ -267,7 +267,7 @@ static void tpm_dev_release(struct device *dev)
>  	idr_remove(&dev_nums_idr, chip->dev_num);
>  	mutex_unlock(&idr_lock);
>  
> -	kfree(chip->log.bios_event_log);
> +	chip->log.release(chip->log.bios_event_log);
>  	kfree(chip->work_space.context_buf);
>  	kfree(chip->work_space.session_buf);
>  	kfree(chip->allocated_banks);
> @@ -324,6 +324,7 @@ struct tpm_chip *tpm_chip_alloc(struct device *pdev,
>  	init_rwsem(&chip->ops_sem);
>  
>  	chip->ops = ops;
> +	chip->log.release = (void(*)(void *))kfree;

Why do you need this cast?

>  
>  	mutex_lock(&idr_lock);
>  	rc = idr_alloc(&dev_nums_idr, NULL, 0, TPM_NUM_DEVICES, GFP_KERNEL);
> diff --git a/include/linux/tpm.h b/include/linux/tpm.h
> index dfeb25a0362d..f1c0b0eb20a5 100644
> --- a/include/linux/tpm.h
> +++ b/include/linux/tpm.h
> @@ -109,6 +109,7 @@ struct tpm_space {
>  struct tpm_bios_log {
>  	void *bios_event_log;
>  	void *bios_event_log_end;
> +	void (*release)(void *ptr);
>  };
>  
>  struct tpm_chip_seqops {
> -- 
> 2.31.1
> 

BR, Jarkko
  

On 1/16/23 00:53, Jarkko Sakkinen wrote:
> On Tue, Jan 03, 2023 at 10:20:10AM -0600, Eddie James wrote:
>> Some platforms may desire to pass the event log up to linux in the
>> form of a reserved memory region. Add support for this in the TPM
>> core to find the reserved memory region and map it.
>>
>> Signed-off-by: Eddie James <eajames@linux.ibm.com>
> Which platforms?
>
> I do not see information of
>
> +	void (*release)(void *ptr);
>
> in the commit message. The description of the implemenation approach is
> missing.


Hi, please see v2 which is a two patch series. I have changed the 
implementation to avoid this release pointer. 
https://patchwork.kernel.org/project/linux-integrity/list/?series=711832


Thanks,

Eddie


>
>
>> ---
>>   drivers/char/tpm/eventlog/of.c | 38 +++++++++++++++++++++++++++++++++-
>>   drivers/char/tpm/tpm-chip.c    |  3 ++-
>>   include/linux/tpm.h            |  1 +
>>   3 files changed, 40 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/char/tpm/eventlog/of.c b/drivers/char/tpm/eventlog/of.c
>> index a9ce66d09a75..0455d7f61c10 100644
>> --- a/drivers/char/tpm/eventlog/of.c
>> +++ b/drivers/char/tpm/eventlog/of.c
>> @@ -11,12 +11,48 @@
>>    */
>>   
>>   #include <linux/slab.h>
>> +#include <linux/io.h>
>> +#include <linux/ioport.h>
>>   #include <linux/of.h>
>> +#include <linux/of_address.h>
>> +#include <linux/of_reserved_mem.h>
>>   #include <linux/tpm_eventlog.h>
>>   
>>   #include "../tpm.h"
>>   #include "common.h"
>>   
>> +static int tpm_read_log_memory_region(struct tpm_chip *chip)
>> +{
>> +	struct device_node *node;
>> +	struct resource res;
>> +	int rc;
>> +
>> +	node = of_parse_phandle(chip->dev.parent->of_node, "memory-region", 0);
>> +	if (!node) {
>> +		dev_info(&chip->dev, "no phandle\n");
>> +		return -ENODEV;
>> +	}
>> +
>> +	rc = of_address_to_resource(node, 0, &res);
>> +	of_node_put(node);
>> +	if (rc) {
>> +		dev_info(&chip->dev, "no mem\n");
>> +		return rc;
>> +	}
>> +
>> +	chip->log.bios_event_log = memremap(res.start, resource_size(&res), MEMREMAP_WB);
>> +	if (!chip->log.bios_event_log) {
>> +		dev_info(&chip->dev, "err memremap\n");
>> +		return -ENOMEM;
>> +	}
>> +
>> +	chip->log.release = memunmap;
>> +	chip->log.bios_event_log_end = chip->log.bios_event_log + resource_size(&res);
>> +
>> +	return chip->flags & TPM_CHIP_FLAG_TPM2 ? EFI_TCG2_EVENT_LOG_FORMAT_TCG_2 :
>> +		EFI_TCG2_EVENT_LOG_FORMAT_TCG_1_2;
>> +}
> We do not want to support TPM 1.2 for new features.
>
>> +
>>   int tpm_read_log_of(struct tpm_chip *chip)
>>   {
>>   	struct device_node *np;
>> @@ -38,7 +74,7 @@ int tpm_read_log_of(struct tpm_chip *chip)
>>   	sizep = of_get_property(np, "linux,sml-size", NULL);
>>   	basep = of_get_property(np, "linux,sml-base", NULL);
>>   	if (sizep == NULL && basep == NULL)
>> -		return -ENODEV;
>> +		return tpm_read_log_memory_region(chip);
>>   	if (sizep == NULL || basep == NULL)
>>   		return -EIO;
>>   
>> diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c
>> index 741d8f3e8fb3..09ea8145d7c6 100644
>> --- a/drivers/char/tpm/tpm-chip.c
>> +++ b/drivers/char/tpm/tpm-chip.c
>> @@ -267,7 +267,7 @@ static void tpm_dev_release(struct device *dev)
>>   	idr_remove(&dev_nums_idr, chip->dev_num);
>>   	mutex_unlock(&idr_lock);
>>   
>> -	kfree(chip->log.bios_event_log);
>> +	chip->log.release(chip->log.bios_event_log);
>>   	kfree(chip->work_space.context_buf);
>>   	kfree(chip->work_space.session_buf);
>>   	kfree(chip->allocated_banks);
>> @@ -324,6 +324,7 @@ struct tpm_chip *tpm_chip_alloc(struct device *pdev,
>>   	init_rwsem(&chip->ops_sem);
>>   
>>   	chip->ops = ops;
>> +	chip->log.release = (void(*)(void *))kfree;
> Why do you need this cast?
>
>>   
>>   	mutex_lock(&idr_lock);
>>   	rc = idr_alloc(&dev_nums_idr, NULL, 0, TPM_NUM_DEVICES, GFP_KERNEL);
>> diff --git a/include/linux/tpm.h b/include/linux/tpm.h
>> index dfeb25a0362d..f1c0b0eb20a5 100644
>> --- a/include/linux/tpm.h
>> +++ b/include/linux/tpm.h
>> @@ -109,6 +109,7 @@ struct tpm_space {
>>   struct tpm_bios_log {
>>   	void *bios_event_log;
>>   	void *bios_event_log_end;
>> +	void (*release)(void *ptr);
>>   };
>>   
>>   struct tpm_chip_seqops {
>> -- 
>> 2.31.1
>>
> BR, Jarkko