Re: linux-next: Tree for Apr 19 (bcache)

Re: linux-next: Tree for Apr 19 (bcache)

[Randy Dunlap]

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On 4/19/21 3:23 AM, Stephen Rothwell wrote:
> Hi all,
> 
> Changes since 20210416:
> 

on x86_64:

when
# CONFIG_BLK_DEV is not set


WARNING: unmet direct dependencies detected for LIBNVDIMM
  Depends on [n]: PHYS_ADDR_T_64BIT [=y] && HAS_IOMEM [=y] && BLK_DEV [=n]
  Selected by [y]:
  - BCACHE_NVM_PAGES [=y] && MD [=y] && BCACHE [=y] && PHYS_ADDR_T_64BIT [=y]


Full randconfig file is attached.

-- 
~Randy
Reported-by: Randy Dunlap <rdunlap@infradead.org>

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Re: linux-next: Tree for Apr 19 (bcache)

[Coly Li]

On 4/19/21 11:40 PM, Randy Dunlap wrote:
> On 4/19/21 3:23 AM, Stephen Rothwell wrote:
>> Hi all,
>>
>> Changes since 20210416:
>>
> 
> on x86_64:
> 
> when
> # CONFIG_BLK_DEV is not set
> 
> 
> WARNING: unmet direct dependencies detected for LIBNVDIMM
>   Depends on [n]: PHYS_ADDR_T_64BIT [=y] && HAS_IOMEM [=y] && BLK_DEV [=n]
>   Selected by [y]:
>   - BCACHE_NVM_PAGES [=y] && MD [=y] && BCACHE [=y] && PHYS_ADDR_T_64BIT [=y]
> 
> 
> Full randconfig file is attached.
> 

I need hint from kbuild expert.

My original idea to use "select LIBNVDIMM" is to avoid the
BCACHE_NVM_PAGES option to disappear if LIBNVDIMM is not enabled.
Otherwise if nvdimm driver is not configure, users won't know there is a
BCACHE_NVM_PAGES option unless they read bcache Kconfig file.

But I see nvdimm's Kconfig, it uses "depends on BLK_DEV", I understand
it is acceptable that LIBNVDIMM option to disappear from "make
menuconfig" if BLK_DEV is not enabled.

For such condition, which one is the proper way to set the dependence ?
- Change "select LIBNVDIMM" and "select DAX" to "depends on LIBNVDIMM"
and "depends on DAX" in bcache Kconfig
- Or change "depends on BLK_DEV" to "select BLK_DEV" in nvdimm Kconfig.


I want to ask for a proper way to handle such dependence, and I will
follow the guide for now and in future.

Thanks in advance for the advice.

Coly Li

Re: linux-next: Tree for Apr 19 (bcache)

[Jens Axboe]

On 4/19/21 10:26 AM, Coly Li wrote:
> On 4/19/21 11:40 PM, Randy Dunlap wrote:
>> On 4/19/21 3:23 AM, Stephen Rothwell wrote:
>>> Hi all,
>>>
>>> Changes since 20210416:
>>>
>>
>> on x86_64:
>>
>> when
>> # CONFIG_BLK_DEV is not set
>>
>>
>> WARNING: unmet direct dependencies detected for LIBNVDIMM
>>   Depends on [n]: PHYS_ADDR_T_64BIT [=y] && HAS_IOMEM [=y] && BLK_DEV [=n]
>>   Selected by [y]:
>>   - BCACHE_NVM_PAGES [=y] && MD [=y] && BCACHE [=y] && PHYS_ADDR_T_64BIT [=y]
>>
>>
>> Full randconfig file is attached.
>>
> 
> I need hint from kbuild expert.
> 
> My original idea to use "select LIBNVDIMM" is to avoid the
> BCACHE_NVM_PAGES option to disappear if LIBNVDIMM is not enabled.
> Otherwise if nvdimm driver is not configure, users won't know there is a
> BCACHE_NVM_PAGES option unless they read bcache Kconfig file.

But why? That's exactly how it should work. Just use depends to set the
dependency.

> But I see nvdimm's Kconfig, it uses "depends on BLK_DEV", I understand
> it is acceptable that LIBNVDIMM option to disappear from "make
> menuconfig" if BLK_DEV is not enabled.
> 
> For such condition, which one is the proper way to set the dependence ?
> - Change "select LIBNVDIMM" and "select DAX" to "depends on LIBNVDIMM"
> and "depends on DAX" in bcache Kconfig
> - Or change "depends on BLK_DEV" to "select BLK_DEV" in nvdimm Kconfig.

The former.

-- 
Jens Axboe

Re: linux-next: Tree for Apr 19 (bcache)

[Coly Li]

On 4/20/21 1:50 AM, Jens Axboe wrote:
> On 4/19/21 10:26 AM, Coly Li wrote:
>> On 4/19/21 11:40 PM, Randy Dunlap wrote:
>>> On 4/19/21 3:23 AM, Stephen Rothwell wrote:
>>>> Hi all,
>>>>
>>>> Changes since 20210416:
>>>>
>>>
>>> on x86_64:
>>>
>>> when
>>> # CONFIG_BLK_DEV is not set
>>>
>>>
>>> WARNING: unmet direct dependencies detected for LIBNVDIMM
>>>   Depends on [n]: PHYS_ADDR_T_64BIT [=y] && HAS_IOMEM [=y] && BLK_DEV [=n]
>>>   Selected by [y]:
>>>   - BCACHE_NVM_PAGES [=y] && MD [=y] && BCACHE [=y] && PHYS_ADDR_T_64BIT [=y]
>>>
>>>
>>> Full randconfig file is attached.
>>>
>>
>> I need hint from kbuild expert.
>>
>> My original idea to use "select LIBNVDIMM" is to avoid the
>> BCACHE_NVM_PAGES option to disappear if LIBNVDIMM is not enabled.
>> Otherwise if nvdimm driver is not configure, users won't know there is a
>> BCACHE_NVM_PAGES option unless they read bcache Kconfig file.
> 
> But why? That's exactly how it should work. Just use depends to set the
> dependency.
> 
>> But I see nvdimm's Kconfig, it uses "depends on BLK_DEV", I understand
>> it is acceptable that LIBNVDIMM option to disappear from "make
>> menuconfig" if BLK_DEV is not enabled.
>>
>> For such condition, which one is the proper way to set the dependence ?
>> - Change "select LIBNVDIMM" and "select DAX" to "depends on LIBNVDIMM"
>> and "depends on DAX" in bcache Kconfig
>> - Or change "depends on BLK_DEV" to "select BLK_DEV" in nvdimm Kconfig.
> 
> The former.
> 

Copied. Thanks for the hint. I will post a fix soon.

Coly Li