Re: kismet: WARNING: unmet direct dependencies detected for HUGETLBFS when selected by PPC_8xx

[Christophe Leroy]

Le 06/02/2025 à 03:08, Miaohe Lin a écrit :
> On 2025/2/6 0:35, Christophe Leroy wrote:
> > Le 05/02/2025 à 03:39, Miaohe Lin a écrit :
> > > On 2025/1/24 6:24, kernel test robot wrote:
> > > > tree:   https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgit.kernel.org%2Fpub%2Fscm%2Flinux%2Fkernel%2Fgit%2Ftorvalds%2Flinux.git&data=05%7C02%7Cchristophe.leroy%40csgroup.eu%7C97f4bcfeef7147c5a46408dd465329e6%7C8b87af7d86474dc78df45f69a2011bb5%7C0%7C0%7C638744045189449604%7CUnknown%7CTWFpbGZsb3d8eyJFbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiTWFpbCIsIldUIjoyfQ%3D%3D%7C0%7C%7C%7C&sdata=x37VZjFG%2BB1zYyoDGgz4jIyUbSWx%2FCklH%2FgsDLGCW%2F4%3D&reserved=0 master
> > > > head:   d0d106a2bd21499901299160744e5fe9f4c83ddb
> > > > commit: f8142cf94d4737ea0c3baffb3b9bad8addcb9b6b hugetlb: make hugetlb depends on SYSFS or SYSCTL
> > > > date:   2 years, 4 months ago
> > > > config: powerpc-kismet-CONFIG_HUGETLBFS-CONFIG_PPC_8xx-0-0 (https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fdownload.01.org%2F0day-ci%2Farchive%2F20250124%2F202501240611.LDmD2nkj-lkp%40intel.com%2Fconfig&data=05%7C02%7Cchristophe.leroy%40csgroup.eu%7C97f4bcfeef7147c5a46408dd465329e6%7C8b87af7d86474dc78df45f69a2011bb5%7C0%7C0%7C638744045189465052%7CUnknown%7CTWFpbGZsb3d8eyJFbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiTWFpbCIsIldUIjoyfQ%3D%3D%7C0%7C%7C%7C&sdata=QSCbgVZFsu%2BQN1b7xDiPsikJR93kWobuPsa%2BtqG3dZA%3D&reserved=0)
> > > > reproduce: (https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fdownload.01.org%2F0day-ci%2Farchive%2F20250124%2F202501240611.LDmD2nkj-lkp%40intel.com%2Freproduce&data=05%7C02%7Cchristophe.leroy%40csgroup.eu%7C97f4bcfeef7147c5a46408dd465329e6%7C8b87af7d86474dc78df45f69a2011bb5%7C0%7C0%7C638744045189472672%7CUnknown%7CTWFpbGZsb3d8eyJFbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiTWFpbCIsIldUIjoyfQ%3D%3D%7C0%7C%7C%7C&sdata=nT4smogT5pTgqIh7%2FCPD%2FpQsCqaBrxfN%2BtEER7l%2FyLY%3D&reserved=0)
> > > >
> > > > If you fix the issue in a separate patch/commit (i.e. not just a new version of
> > > > the same patch/commit), kindly add following tags
> > > > | Reported-by: kernel test robot <lkp@xxxxxxxxx>
> > > > | Closes: https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Flore.kernel.org%2Foe-kbuild-all%2F202501240611.LDmD2nkj-lkp%40intel.com%2F&data=05%7C02%7Cchristophe.leroy%40csgroup.eu%7C97f4bcfeef7147c5a46408dd465329e6%7C8b87af7d86474dc78df45f69a2011bb5%7C0%7C0%7C638744045189480482%7CUnknown%7CTWFpbGZsb3d8eyJFbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiTWFpbCIsIldUIjoyfQ%3D%3D%7C0%7C%7C%7C&sdata=7yBcNLgmgW6BUZ55nHh%2F8fZqHGShaqGDKdotvIQ2Tl8%3D&reserved=0
> > >
> > > Thanks for report. Sorry for late respond. I was on my Spring Festival vacation.
> > >
> > > > kismet warnings: (new ones prefixed by >>)
> > > > > > kismet: WARNING: unmet direct dependencies detected for HUGETLBFS when selected by PPC_8xx
> > > >      WARNING: unmet direct dependencies detected for HUGETLBFS
> > > >        Depends on [n]: (X86 || IA64 || SPARC64 || ARCH_SUPPORTS_HUGETLBFS [=y] || BROKEN [=n]) && (SYSFS [=n] || SYSCTL [=n])
> > > >        Selected by [y]:
> > > >        - PPC_8xx [=y] && <choice>
> > >
> > > I am a bit confused. HUGETLBFS depends on SYSFS or SYSCTL. How can it be selected while SYSFS [=n] || SYSCTL [=n]?
> > > Or am I miss something?
> >
> > CONFIG_HUGETLBFS is selected by CONFIG_PPC_8xx, see commit 34536d780683 ("powerpc/8xx: Add a function to early map kernel via huge pages")
>
> Thanks for your providing. But I'm saying that since HUGETLBFS depends on (SYSFS or SYSCTL), how CONFIG_PPC_8xx succeeds to select it while
> SYSFS and SYSCTL are disabled? I'm not really familiar with Kconfig but I assume Kconfig will confirm that the dependencies are satisfied
> before HUGETLBFS is enabled. Or am I miss something?

I suggest you read https://docs.kernel.org/kbuild/kconfig-language.html

Extract:

Note:
    select should be used with care. select will force a symbol to a 
value without visiting the dependencies. By abusing select you are able 
to select a symbol FOO even if FOO depends on BAR that is not set.

Christophe