[PATCH 3/3] commands: add new devunbind debugging command

[Ahmad Fatoum]

On 10.01.22 09:56, Sascha Hauer wrote:
> On Sat, Jan 08, 2022 at 06:14:26PM +0100, Ahmad Fatoum wrote:
>> Memory corruption around device removal may go unnoticed, because
>> barebox is shutting down anyway and doing no new allocations.
>>
>> Add a new devunbind command that should help with debugging such issues
>> by allowing selective unbinding and removal of devices.
>>
>> Signed-off-by: Ahmad Fatoum <a.fatoum at pengutronix.de>
>> ---
>>  commands/Kconfig      | 12 +++++++
>>  commands/Makefile     |  1 +
>>  commands/devunbind.c  | 74 +++++++++++++++++++++++++++++++++++++++++++
>>  drivers/base/driver.c |  7 ++--
>>  include/driver.h      |  4 +++
>>  5 files changed, 95 insertions(+), 3 deletions(-)
>>  create mode 100644 commands/devunbind.c
>>
>> diff --git a/commands/Kconfig b/commands/Kconfig
>> index e2c36949347e..9abd97271952 100644
>> --- a/commands/Kconfig
>> +++ b/commands/Kconfig
>> @@ -68,6 +68,18 @@ config CMD_DEVINFO
>>  	  If called with a device path being the argument, devinfo shows more
>>  	  default information about this device and its parameters.
>>  
>> +config CMD_DEVUNBIND
>> +	tristate
>> +	default y
>> +	prompt "devunbind"
>> +	help
>> +	  Debugging aid to unbind device from driver at runtime
>> +
>> +	  devunbind [-f] DEVICE
>> +
>> +	  Options:
>> +	    -f   unbind driver and force removal of device and children
>> +
>>  config CMD_DMESG
>>  	tristate
>>  	prompt "dmesg"
>> diff --git a/commands/Makefile b/commands/Makefile
>> index 0b7c1563b534..875826743ffe 100644
>> --- a/commands/Makefile
>> +++ b/commands/Makefile
>> @@ -107,6 +107,7 @@ obj-$(CONFIG_CMD_MIITOOL)	+= miitool.o
>>  obj-$(CONFIG_CMD_DETECT)	+= detect.o
>>  obj-$(CONFIG_CMD_BOOT)		+= boot.o
>>  obj-$(CONFIG_CMD_DEVINFO)	+= devinfo.o
>> +obj-$(CONFIG_CMD_DEVUNBIND)	+= devunbind.o
>>  obj-$(CONFIG_CMD_DRVINFO)	+= drvinfo.o
>>  obj-$(CONFIG_CMD_READF)		+= readf.o
>>  obj-$(CONFIG_CMD_MENUTREE)	+= menutree.o
>> diff --git a/commands/devunbind.c b/commands/devunbind.c
>> new file mode 100644
>> index 000000000000..4bebb27e8e68
>> --- /dev/null
>> +++ b/commands/devunbind.c
>> @@ -0,0 +1,74 @@
>> +// SPDX-License-Identifier: GPL-2.0-only
>> +// SPDX-FileCopyrightText: © 2021 Ahmad Fatoum <a.fatoum at pengutronix.de>, Pengutronix
>> +
>> +#include <command.h>
>> +#include <common.h>
>> +#include <complete.h>
>> +#include <driver.h>
>> +#include <getopt.h>
>> +
>> +static int do_devunbind(int argc, char *argv[])
>> +{
>> +	bool unregister = false;
>> +	struct device_d *dev;
>> +	int ret = COMMAND_SUCCESS, i, opt;
>> +
>> +	while ((opt = getopt(argc, argv, "fl")) > 0) {
>> +		switch (opt) {
>> +		case 'f':
>> +			unregister = true;
>> +			break;
>> +		case 'l':
>> +			list_for_each_entry(dev, &active_device_list, active) {
>> +				BUG_ON(!dev->driver);
>> +				if (dev->bus->remove)
>> +					printf("%pS(%s, %s)\n", dev->bus->remove,
>> +					       dev->driver->name, dev_name(dev));
>> +			}
>> +			return 0;
>> +		default:
>> +			return COMMAND_ERROR_USAGE;
>> +		}
>> +	}
>> +
>> +	if (!argv[optind])
>> +		return COMMAND_ERROR_USAGE;
>> +
>> +	for (i = optind; i < argc; i++) {
>> +		dev = get_device_by_name(argv[i]);
>> +		if (!dev)
>> +			return -ENODEV;
>> +
>> +		if (unregister)
>> +			return unregister_device(dev);
> 
> Shouldn't you continue the loop here?

Yes. Fixed in v2.

> 
> Sascha
> 


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