[U-Boot] [PATCH v2] cmd: usb_mass_storage: add protection for block_dev

[Marek Vasut]

On 09/28/2018 11:30 AM, Patrick DELAUNAY wrote:
> Hi,

Hi,

>> From: Marek Vasut <marex at denx.de>
>>
>> On 09/26/2018 01:04 PM, Patrick Delaunay wrote:
>>> solve data abort for the command "ums 0 ubi 0"
>>> because result of case blk_get_device_part_str() result is OK but with
>>> block_dev = 0 when CONFIG_CMD_UBIFS is activate and ubi volume is
>>> mounted
>>
>> I don't quite understand the commit message, can you reword it?
> 
> Ok, I prepare a V3 

Sending a V3 while discussion is ongoing is pointless.

>> Also, when is this ever called with block_dev == NULL ? What's the condition to
>> trigger this and why ?
> 
> To reproduce the issue you need to have a ubifs  already mounted,
> for example with the command:
> 	ubi part UBI
>  	ubifsmount ubi0:boot
> 
> I investigate the point, the call stack before the crash is  caused by the ubi support in 
> ./disk/part.c:425 =  blk_get_device_part_str()
> 
> Some part of code here are under CONFIG_CMD_UBIFS with the comment :
> 	"ubi goes through a mtd, rathen then through a regular block device"
> 
> So the the function return a pointer to disk_partition_t :
> 		info->type = BOOT_PART_TYPE
> 		info->name =  "UBI"
>  but without block device information !
> 		*dev_desc = NULL

Would it rather make sense to fix it here , so it has a valid dev_desc ?

> So the issue occurs because, when the ubifs volume is mounted,
> The code in  cmd/usb_mass_storage.c
[...]

-- 
Best regards,
Marek Vasut