On Fri, Jul 13, 2012 at 10:54 PM, Myklebust, Trond wrote:

We could at least make selection of a minimal set of drivers for the more common virtualised platforms a lot easier. Right now, you need to hunt through 30+ different menus in order to find what you need to run in a basic KVM virtual machine...

Yes, every time I build a kernel to be used on KVM I forget something. :-\ We could introduce a section in Kconfig which contains selections for common use cases. E.g. as Linus requested for minimal distro requirements but also selections for various common guest configurations. -- Thanks, //richard -- To unsubscribe, e-mail: opensuse-kernel+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-kernel+owner@opensuse.org

On Sat, Jul 14, 2012 at 1:37 PM, Borislav Petkov wrote:

On Fri, Jul 13, 2012 at 11:41:21PM +0200, richard -rw- weinberger wrote:

...

On Fri, Jul 13, 2012 at 10:54 PM, Myklebust, Trond wrote:

...

We could at least make selection of a minimal set of drivers for the more common virtualised platforms a lot easier. Right now, you need to hunt through 30+ different menus in order to find what you need to run in a basic KVM virtual machine...

Yes, every time I build a kernel to be used on KVM I forget something. :-\

We could introduce a section in Kconfig which contains selections for common use cases. E.g. as Linus requested for minimal distro requirements but also selections for various common guest configurations.

+1.

Same experience with building a kvm kernel so I couldn't agree more.

We have "make kvmconfig" in the KVM tool tree that pretty much does that automatically. There's nothing tools/kvm specific about it so I guess you could merge that separately. Pekka -- To unsubscribe, e-mail: opensuse-kernel+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-kernel+owner@opensuse.org

On Sat, Jul 14, 2012 at 04:43:32PM +0400, Cyrill Gorcunov wrote:

For example to enable "PCI driver for virtio devices" I need to go to Device Drivers -> Virtio drivers, while I think it would be great to have everything virt. related in Virtualization section.

Actually, we need something more generic than that: everything X-related should be automatically selected when setting CONFIG_X. And X can be any subset of configuration options which belong to one feature, be it KVM, distro-specific stuff, or CPU-vendor specific stuff, or whatever. I can imagine, for example, that when a user wants to have an AMD-specific config, it automatically selects CPU_SUP_AMD, X86_MCE_AMD (for MCE), MICROCODE_AMD (microcode support), AGP_AMD64, EDAC_AMD64 and a bunch of other AMD-specific features. This would simplify not only the configuration process but also Kconfig-related build failures since for your configuration you'll make sure that required stuff is selected. What I'm saying is that not only distro-specific configs but also some sort of hierarchical config options could be defined to automatically preselect stuff for a specific aspect and save a lot of time when configuring a new system. Our config options have grown humongous right about now and we can use the simplification. Of course, you can always do fine-grained tuning afterwards but it'll save a lot of time, in general. Let's have an example: when I have to build upstream on a distro here, I take the distro config and use it despite that it takes a long time to build since everything is module - it is still better for me to wait that one time instead of doing a dozen of trial and errors after forgetting a config option each time. Thanks. -- Regards/Gruss, Boris. Advanced Micro Devices GmbH Einsteinring 24, 85609 Dornach GM: Alberto Bozzo Reg: Dornach, Landkreis Muenchen HRB Nr. 43632 WEEE Registernr: 129 19551 -- To unsubscribe, e-mail: opensuse-kernel+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-kernel+owner@opensuse.org

On Sat, 14 Jul 2012, Cyrill Gorcunov wrote:

On Sat, Jul 14, 2012 at 07:48:27PM +0200, Borislav Petkov wrote:

...

On Sat, Jul 14, 2012 at 04:43:32PM +0400, Cyrill Gorcunov wrote:

...

For example to enable "PCI driver for virtio devices" I need to go to Device Drivers -> Virtio drivers, while I think it would be great to have everything virt. related in Virtualization section.

Actually, we need something more generic than that: everything X-related should be automatically selected when setting CONFIG_X. And X can be any subset of configuration options which belong to one feature, be it KVM, distro-specific stuff, or CPU-vendor specific stuff, or whatever.

I can imagine, for example, that when a user wants to have an AMD-specific config, it automatically selects CPU_SUP_AMD, X86_MCE_AMD (for MCE), MICROCODE_AMD (microcode support), AGP_AMD64, EDAC_AMD64 and a bunch of other AMD-specific features.

sure, no doubts, it would be great! (I must admit I never looked up into kconfig parser code so i don't know if this could be achieved easily).

think of this as a variation of the miniconfig problem. Instead of the miniconfig being one file that specifies everything you want, that you then use to generate a real .config file, you instead have one _or_ _more_ config files that get combined and then used to generate the real .config file. Doing this as a set of miniconfig snippets instead of as menu options in the main kconfig has the advantage that once the real .config is created, it can then be edited freely, without worrying about things like SELINUX being enabled when you want to do development on a different LSM. The distro config would be the first of these, but then you could have multiple hardware specific config files (a vmware config, a KVM config, one or more config files for the systems that you own, a USB config to enable a bunch of the various USB deices that you want to support, etc) The distros may choose to produce several miniconfig files, one the minimum infrastructure features they need, and then additional files for the rest of their config. For example, I could see them having a set of files 1. Core 2. architecture 3. architecture specific drivers 4. architecture neutral drivers (USB devices and similar) starting off with the distro config, the people creating this are going to be very familiar with kconfig and could create these by hand, but going forward we are going to want to have some tools to help sysadmins to create these files. Not knowing kconfig, it may be as simple as taking the miniconfig snippets that you start with, creating a .config and then doing a diff of that .config with the one the admin created, using the result as the new miniconfig snippet. David Lang -- To unsubscribe, e-mail: opensuse-kernel+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-kernel+owner@opensuse.org

On Thu, Jul 19, 2012 at 10:42:17AM -0400, Steven Rostedt wrote:

On Sat, Jul 14, 2012 at 07:48:27PM +0200, Borislav Petkov wrote:

...

Let's have an example: when I have to build upstream on a distro here, I take the distro config and use it despite that it takes a long time to build since everything is module - it is still better for me to wait that one time instead of doing a dozen of trial and errors after forgetting a config option each time.

This is where 'make localmodconfig' does help. It can remove a lot of modules for you. And I just recently fixed a bug in the tool that it now removes even more modules (The fix is in linux-next).

Even more modules? When is enough, enough? :-)

Also, if you are building on another box than what the kernel is for, you can go to that box and run 'lsmod > /tmp/lsmod'. Copy that file to the build machine (into /tmp/lsmod), and then run 'make LSMOD=/tmp/lsmod localmodconfig', and this will remove the modules not used by the target box.

Seriously, this helps only in the cases where the stuff the distro actually needs is in modules. So, there probably are obscure situations where you need to enable stuff which is bool and not M. Hopefully those cases are seldom enough so thanks for this, I'll try that the next time. -- Regards/Gruss, Boris. Advanced Micro Devices GmbH Einsteinring 24, 85609 Dornach GM: Alberto Bozzo Reg: Dornach, Landkreis Muenchen HRB Nr. 43632 WEEE Registernr: 129 19551 -- To unsubscribe, e-mail: opensuse-kernel+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-kernel+owner@opensuse.org

On Thu, Jul 19, 2012 at 01:02:46PM -0400, Steven Rostedt wrote:

This is why I created the make-min-config in ktest. It keeps on disabling configs to see what the machine needs to boot (and optionally run some test), and what configs it can disable. It does not touch the multi options though.

It creates two configs. One that has the configs that it can't turn off (still enabled with a make allnoconfig, or selected by something that it must have), and a config that just has the configs that 'if I disable this, the box doesn't boot'.

Here's an example:

For my min-config files with the configs that couldn't be turned off:

$ wc -l config-min* 117 config-min 139 config-min-net

The config-min will get the box to boot (no network). The -net, adds enough to ssh to the box.

$ wc -l config-skip* 11 config-skip 14 config-skip-net

The above are the configs that ktest found if it disabled, would not boot (or ssh).

$ cat config-skip-net CONFIG_SERIAL_8250_CONSOLE=y CONFIG_SATA_AHCI=y CONFIG_E1000=y CONFIG_QUOTA=y CONFIG_ATA=y CONFIG_UNIX=y CONFIG_INET=y CONFIG_DEVTMPFS=y CONFIG_EXT4_FS=y CONFIG_DEVTMPFS_MOUNT=y CONFIG_SERIAL_8250=y CONFIG_BLK_DEV_SD=y CONFIG_NET=y CONFIG_NETDEVICES=y

I can pass the above to a allnoconfig, and the box will boot and allow ssh. Note, the reason for the serial config, is that this ktest run uses a serial port to see if the box booted. If the serial isn't there, then it thinks it failed.

I agree with all this and you've explained this to me live already so you're preaching to the choir. But it would be a lot faster/easier if users can select, let's call'em "profiles" which are not mutually exclusive and can speed up the configuration process. They can either be distro-specific or generic, selecting certain features you need. So configuring your kernel would be like shopping without paying too much attention to details. Let's look into the head of a person doing a config like that and read some of her thoughts :): "Hm, ok, this new configurator is cool, a lot faster I gotta say... So, what do I need, ah, yes, it is an AMD laptop so from vendors I select AMD, then I probably need ext4, then I'd like to do packet filtering so I should enable iptables.. Oh, I'd like to do tracing too so let's enable tracing and trust Steven with the options he's added by default, then I need ahci, I'd also like to do encrypted partitions so I'll enable device mapper with crypto... " So all those things could be selectable from that profiles menu without having to go through the gazillion of little suboptions and having to read help (which is sometimes completely helpless) and figure out do I need it or not. And this would simplify configuration a lot. IMHO, anyway. -- Regards/Gruss, Boris. Advanced Micro Devices GmbH Einsteinring 24, 85609 Dornach GM: Alberto Bozzo Reg: Dornach, Landkreis Muenchen HRB Nr. 43632 WEEE Registernr: 129 19551 -- To unsubscribe, e-mail: opensuse-kernel+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-kernel+owner@opensuse.org

On Thu, Jul 19, 2012 at 01:57:26PM -0400, Steven Rostedt wrote:

Yes, I know you know this already, as we discussed it in a pub over a beer (choir practice). But this is a public forum on LKML (the church), where I now have an audience of heathens. Convert! Convert! You are all sinners!

Ah, gotcha. [ … ]

But this still doesn't solve Linus's initial request. That would be a single option that makes your distro boot, and work well. Again, that option wont have the drivers needed, but it will enable all the core infrastructure that you need.

Oh I'm being additive here. You'll have feature profiles for the stuff we talk above and distro profiles which solve Linus' issue. Basically one coarse-grained config option will either select a feature which has a lot of small subfeatures of which some are sane and want to be enabled by default when selecting the topfeature. Or a distro-specific feature which could itself select other topfeatures. I haven't tried this in reality to actually be able to say that a tree-like configure approach would actually make sense and work. It sounds like a nice idea though, especially having the hierarchical structure. :) -- Regards/Gruss, Boris. Advanced Micro Devices GmbH Einsteinring 24, 85609 Dornach GM: Alberto Bozzo Reg: Dornach, Landkreis Muenchen HRB Nr. 43632 WEEE Registernr: 129 19551 -- To unsubscribe, e-mail: opensuse-kernel+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-kernel+owner@opensuse.org

On Thu, Jul 19, 2012 at 10:06:44AM -0700, Linus Torvalds wrote:

On Thu, Jul 19, 2012 at 9:48 AM, Borislav Petkov wrote:

...

Seriously, this helps only in the cases where the stuff the distro actually needs is in modules. So, there probably are obscure situations where you need to enable stuff which is bool and not M.

Sadly, not obscure at all.

Most of the *drivers* are modules, but most of the "distro config" options are indeed booleans (or, if tristate, =y).

Even driver-wise, there are some things that are often =y, even though you generally don't want them.

Tell me about it. I'm always pissed off when someone thinks his stuff is very important and sets his sacred option to be =y/=m by default so the wider audience can at least compile-test it while the majority of the machines don't actually need it. A more coarse-grained config where most of the stuff is off by default could take care of that probably.

PCMCIA? Not even *laptops* have that shit any more, but having built-in cardbus support almost certainly helps in a distro kernel for booting of certain odder cases.

Yeah, distros need the one-size-fits-all thing so they have to enable *everything*.

Xen support? Odd partition tables? All the different AGP versions? Many of us couldn't care less, but again, it makes sense in the actual distro kernel, even if it does *not* necessarily make sense in a personalized one.

Yep.

So doing "make allmodconfig" is certainly a workable thing (modulo the modules that you need for stuff you hadn't happened to use), but it's not wonderful.

Oh and I always aim to build distro kernels on a big machine - allmodconfig build is no fun on a tiny laptop. So would it be better to have better profiled kernels, obviating the need for an almost full build? Hell yeah!

I also hate having to enable support for modules. A non-modular build is quicker to build and avoids some security issues. Some drivers don't work well built-in (they load firmware etc too early), but imho it's worth doing if you can, and it's something we should make easy for people to do because of the security side (of course, per-build randomly generated keys and signed modules with the keys deleted after the build would be reasonably equivalent from a security standpoint, but we're not there yet).

Agreed. So there are some not-so-obscure situations, judging by your examples above. Ho-humm. -- Regards/Gruss, Boris. Advanced Micro Devices GmbH Einsteinring 24, 85609 Dornach GM: Alberto Bozzo Reg: Dornach, Landkreis Muenchen HRB Nr. 43632 WEEE Registernr: 129 19551 -- To unsubscribe, e-mail: opensuse-kernel+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-kernel+owner@opensuse.org

On Sat, Jul 14, 2012 at 03:12:05PM +0300, Pekka Enberg wrote:

We have "make kvmconfig" in the KVM tool tree that pretty much does that automatically. There's nothing tools/kvm specific about it so I guess you could merge that separately.

Yes, something like KVMTOOL_TEST_ENABLE except not a make target but a Kconfig option. I can imagine a user selecting this and other coarse-grained options in Kconfig and then "adjusting" single options like, for example, I wouldn't need the *9P* options on x86, etc, etc. Thanks. -- Regards/Gruss, Boris. Advanced Micro Devices GmbH Einsteinring 24, 85609 Dornach GM: Alberto Bozzo Reg: Dornach, Landkreis Muenchen HRB Nr. 43632 WEEE Registernr: 129 19551 -- To unsubscribe, e-mail: opensuse-kernel+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-kernel+owner@opensuse.org

On Sun, Jul 15, 2012 at 01:17:16PM +0300, Pekka Enberg wrote:

...

Yes, something like KVMTOOL_TEST_ENABLE except not a make target but a Kconfig option.

It is a config option too - "make kvmconfig" simply enables it.

Right, so how about something more concrete in this whole discussion: Maybe add the KVMTOOL_TEST_ENABLE (maybe rename it to a more fitting name like KVM_OPTS or similar) thing to a new toplevel Kconfig menu called "Distro and other profiles" or so: │ │ General setup ---> │ │ Distros and other profiles ---> <--- │ │ [*] Enable loadable module support ---> │ │ [*] Enable the block layer ---> │ │ Processor type and features ---> ... Btw, which Kconfig option is needed for "-usbdevice tablet" support so that the host mouse can be able to send scroll events to the guest qemu screen without the need for the qemu screen to capture it so that I need to "escape" it everytime I need to return to the host? And can we add it to the list of options KVMTOOL_TEST_ENABLE selects? Thanks. -- Regards/Gruss, Boris. Advanced Micro Devices GmbH Einsteinring 24, 85609 Dornach GM: Alberto Bozzo Reg: Dornach, Landkreis Muenchen HRB Nr. 43632 WEEE Registernr: 129 19551 -- To unsubscribe, e-mail: opensuse-kernel+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-kernel+owner@opensuse.org

On Mon, 16 Jul 2012, Cyrill Gorcunov wrote:

Replying to David's message (sorry for delay) I fear having a bunch of miniconfig files will end up in a mess. Maybe (maybe (!) I don't know since I've no time at moment to read kconfig code and I'm not sure if this is right direction at all) it would worth to add some new keyword to kconfig language, say "profile", which would tag symbol to a category if needed, and these categories included into profiles automatically. On the other hands this might end up in a mess as well.

I have a couple problems with the approach of modifying the existing kconfig files 1. how does it handle the case when a profile wants something one way and the admin wants it another way the example is the fedora default wanting SELINUX and I want some other LSM 2. since it requires making changes in the upstream kernel source, the number of people who can make these changes is small. 3. since all these changes go into the upstream kernel source, changes to these profiles are going to be visible churn (think of the issues with the defconfigs for ARM a couple of years ago) 4. the complexity of tagging all possible profiles is very high. Even if you limit the profiles to "Linux Distros", how many different distros are there? Do you really want to have to start arguing over which distros are large enough to get their profile added to the upstream kernel source? If instead we go with something along the lines of the miniconf approach, the picture looks very different 1. this approach only sets things one time, after that the person doing the compile is free to change anything. 2. since the changes are a local file, separate from the upstream source, issues like who can provide the config, what distros will accept it, complexity in having many different options, etc all vanish 3. by simply combining miniconfig files, you can combine sets of pre-defined options David Lang -- To unsubscribe, e-mail: opensuse-kernel+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-kernel+owner@opensuse.org

On Mon, 16 Jul 2012, Cyrill Gorcunov wrote:

On Sun, Jul 15, 2012 at 03:09:12PM -0700, david@lang.hm wrote:

...

3. by simply combining miniconfig files, you can combine sets of pre-defined options

Wait, David, I'm lost. These miniconfigs should live somewhere on my home directory (if they are out of mainline tree)?

the distro provided miniconfig files should live in a "known location" (like the distro specific scripts for "make install", but I'm saying that we should be able to use this same mechanism to include locally generated files. combining external files doesn't need to be the job of the kernel kconfig infrastructure either. There could be external scripts that take one or more distro provided files and one or more local files and combine them for the kconfig infrastructure. For a distro, I could see their build farm using this as well, with a file organization along the lines of base config arch specific options (one per arch) generic drivers (USB devices, etc) This sort of thing would help reduce the chances of there being unexpected differences between the different architecture builds. this can be done without having to modify the existing kconfig stuff at all (by using make oldconfig), but it's likely that a little bit of support from kconfig could make creating these miniconifg files much easier. Linus started off wanting the core requirements, other people want to duplicate the full distro kernel, others want everything but the drivers, others want to substatute a list of driver options that their local systems need, etc. by using separate files that are external to the kconfig files in the kernel.org source tree, I think that all these people can be satisfied without an explosion of complexity in the source tree. David Lang -- To unsubscribe, e-mail: opensuse-kernel+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-kernel+owner@opensuse.org

On Mon, 16 Jul 2012, Borislav Petkov wrote:

On Sun, Jul 15, 2012 at 03:09:12PM -0700, david@lang.hm wrote:

...

On Mon, 16 Jul 2012, Cyrill Gorcunov wrote:

...

Replying to David's message (sorry for delay) I fear having a bunch of miniconfig files will end up in a mess. Maybe (maybe (!) I don't know since I've no time at moment to read kconfig code and I'm not sure if this is right direction at all) it would worth to add some new keyword to kconfig language, say "profile", which would tag symbol to a category if needed, and these categories included into profiles automatically. On the other hands this might end up in a mess as well.

I have a couple problems with the approach of modifying the existing kconfig files

1. how does it handle the case when a profile wants something one way and the admin wants it another way

Select the profile and then fixup the config the normal way.

If what the admin wants is incompatible with the profile, admin doesn't select the profile.

...

the example is the fedora default wanting SELINUX and I want some other LSM

Currently, if you run fedora and want something that's not enabled, you recompile your kernel too, right?

The problem is that you can't select the Fedora profile and then unselect SELINUX, so the profile will do you no good. It's not a matter of needing to recompile or not, it's a mattter that when you want to recompile, you want to be able to easily select the infrastructure pieces that the distro needs to operate, without also getting their huge selection of 'other' things.

...

2. since it requires making changes in the upstream kernel source, the number of people who can make these changes is small.

I think that's moot since you either select the profile or you don't.

...

3. since all these changes go into the upstream kernel source, changes to these profiles are going to be visible churn (think of the issues with the defconfigs for ARM a couple of years ago)

AFAICT, those changes will be needed only for a new distro release and that happens twice a year, tops.

...

4. the complexity of tagging all possible profiles is very high.

That's why we start simple.

...

Even if you limit the profiles to "Linux Distros", how many different distros are there? Do you really want to have to start arguing over which distros are large enough to get their profile added to the upstream kernel source?

That's a valid question; its answer could be defined arbitrarily.

<joshing> Let's say all distros which make money - more than a certain large amount - are allowed. :-) </joshing>

So that would eliminate all linux distros except for Red Hat Enterprise and Suse (including eliminating opensuse and fedora), somehow I don't think that would produce the benefit that Linus was looking for.

...

If instead we go with something along the lines of the miniconf approach, the picture looks very different

1. this approach only sets things one time, after that the person doing the compile is free to change anything.

...

Sorry, I don't see the simplification: you need to rebuild your kernel anyway and before you rebuild it, you can do all the changes you want. So either you select a profile or you load a miniconfig, it doesn't really matter how you do it?

Yes, you have to recompile in any case. The difference is that with a profile, the profile must be in the kernel source, and you will have problems if you want to start with the profile and then tweak something. with miniconfig, you can have locally defined configs, you can combine multiple configs, and the configs define a starting point, but you can then override them if you want to. David Lang -- To unsubscribe, e-mail: opensuse-kernel+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-kernel+owner@opensuse.org

On Mon, 16 Jul 2012, Linus Torvalds wrote:

On Mon, Jul 16, 2012 at 9:43 AM, wrote:

...

The problem is that you can't select the Fedora profile and then unselect SELINUX, so the profile will do you no good.

Guys, stop it now.

Your "problem" isn't what any sane person cares about, and isn't what I started the RFC for.

Seriously. NOBODY CARES.

You can do what you want to do *today*. Just edit the config file, or use any of the millions of config tools. Stop whining.

The thing I'm asking for is for normal people. Make it easy for people who DO NOT CARE about the config file to just build a kernel for their machine.

Don't complicate the issue by bringing up some totally unrelated question. Don't derail a useful feature for the 99% because you're not in it.

Some of the proposed ways to implement the minimum distro kernel would not allow you to override the distro defaults because they would be implemented by setting dependancies, not by selecting options that you as the user could then unselect. If you have to edit the .config file, and then have your next make *config override your edits (due to dependancy resolution) and so have to edit the .config file again this is a really ugly way of working. David Lang -- To unsubscribe, e-mail: opensuse-kernel+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-kernel+owner@opensuse.org

On Mon, 16 Jul 2012, Linus Torvalds wrote:

On Mon, Jul 16, 2012 at 12:26 PM, wrote:

...

Some of the proposed ways to implement the minimum distro kernel would not allow you to override the distro defaults because they would be implemented by setting dependancies, not by selecting options that you as the user could then unselect.

The sanest thing to do is just a list of "select" statements. And in any case it would have to depend on the "distro config" entry, so EVEN THEN you could just create the Kconfig file, then edit out the distro config thing, and then do whatever you want.

So I don't see why you're arguing. Even if it is very much a "if you select the FEDORA_X kconfig option, that will automatically force all those other options on", I don't see why you are so upset. Just set it, generate your kconfig, and then edit to file to NOT set the distro config. Then you can do whatever the hell you want.

What I'm upset about is simply the fact that EVEN IF your arguments were valid (and I don't think they are: see above for trivial fix) I think your arguments are bogus, for the simple reason that what you ask for isn't even what the whole "distro minconfig" is at all about. It's about normal users who absolutely DO NOT want to edit the config. People who want to say "I know I have intel/amd/nvidia graphics, standard USB, and no CD-ROM drive". They couldn't care *less* about SELINUX, and in fact that very issue is why we should have this.

Anybody who says "I want to run Fedora without SELINUX because I do my own security development" is by *definition* not relevant to the whole feature.

Don't mistake the example for the feature. the SELINUX thing is just an example. As Alan Cox commented, taking a distro config and disabling one thing is a common troubleshooting request from kernel developers. I am not that familiar with the internals of kconfig, but my understanding was that if you select feature X that then turns on A, B, and C, if you then edit the .config file to remove feature X features A, B, and C will be turned off the next time you do a make *config. If this is not the case, then it's not as horrible as I was thinking. However, there's still the question of how many different variations of how many different distros are you going to accept into the upstream kernel. How many different versions of Fedora are you going to be willing to have in the menu? This seems to me to be the defconfig problem multiplied by many distros and many versions of each distro. If we can eliminate this combinational explosion by referencing something outside of the kernel tree, it seems to me that it's a big win. As Alan Cox put it in code

make distroconfig [cp /etc/system-kconfig(.$ARCH?) .config make oldconfig]

make menuconfig (if you want to customise)

with the distros providing /etc/system-kconfig files seems far more scalable as well as far more flexible than either setting up a lot of dependancies for new tags or adding a field to every option to make it part of some profile. This approach works both for the users who just want to say "I know I have intel/amd/nvidia graphics, standard USB, and no CD-ROM drive", for the users who know a bit more, but want to start with a known point, and for the production sysadmins who want to use the same mechanism for other purposes (standardizing builds for systems as kernel versions move forward) David Lang -- To unsubscribe, e-mail: opensuse-kernel+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-kernel+owner@opensuse.org

On Wed, 18 Jul 2012, Ingo Molnar wrote:

* david@lang.hm wrote:

...

...

Anybody who says "I want to run Fedora without SELINUX because I do my own security development" is by *definition* not relevant to the whole feature.

Don't mistake the example for the feature. the SELINUX thing is just an example. As Alan Cox commented, taking a distro config and disabling one thing is a common troubleshooting request from kernel developers.

It's still irrelevant:

- if a user chooses a distro config it means that he is using that distro. Disabling an essential component of the distro config, even if a kernel developer asks for it, will likely break that distro and is thus a dumb thing to do. (the typical user will also be unlikely to be *able* to edit a .config and make sure it works.)

that's assuming that everything listed really is essential. The history of features defaulting to 'Y' in the existing kernel config doesn't give me great confidence that reality will be anywhere close to this ideal.

- Furthermore, there's *already* over ten thousand select's in our Kconfig's, and it's already hard at times to disable dependent options.

- I've been using what Linus suggested for many years via private patches to do bootable randconfig testing and the concept works just fine - enabling a distro specific minconfig is absolutely useful, I'm glad it's being pursued upstream as well...

So what you are arguing about is IMO irrelevant, it is immaterial to the problem at hand and the concept works just fine in practice.

Shrug, you guys have to maintain the result, I'm just a user. But I don't see why the same logic that kept the kernel installation outside of the makefiles and created /sbin/installkernel wouldn't also apply here. using a separate miniconfig in a known place would seem to be less code, distribute the work better (as every distro can use it without having to patch the same files in the kernel source), and be more flexible. Flexibility has a way of being leveraged in ways never imagined initially, so if it can be gained without complicating the code (and it's maintinance), and the initial use case, I always tend to push for the more flexible option. David Lang -- To unsubscribe, e-mail: opensuse-kernel+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-kernel+owner@opensuse.org

On Mon, Jul 16, 2012 at 10:56 PM, Linus Torvalds wrote:

On Mon, Jul 16, 2012 at 12:26 PM, wrote:

...

Some of the proposed ways to implement the minimum distro kernel would not allow you to override the distro defaults because they would be implemented by setting dependancies, not by selecting options that you as the user could then unselect.

The sanest thing to do is just a list of "select" statements. And in any case it would have to depend on the "distro config" entry, so EVEN THEN you could just create the Kconfig file, then edit out the distro config thing, and then do whatever you want.

Except that "select" is one of the ugliest things in Kconfig, as it blindly sets a symbol without checking if its dependencies are fulfilled. Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds -- To unsubscribe, e-mail: opensuse-kernel+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-kernel+owner@opensuse.org

Select the profile and then fixup the config the normal way.

If what the admin wants is incompatible with the profile, admin doesn't select the profile.

Thats ugly - "distro except..." is a standard thing you ask users to do for debugging. However providing you separate the initial profile from the later tools it simply becomes make distroconfig [cp /etc/system-kconfig(.$ARCH?) .config make oldconfig] make menuconfig (if you want to customise) In addition the make oldconfig means you can ship a deliberately incomplete distroconfig and get the user asked some bits. make -- To unsubscribe, e-mail: opensuse-kernel+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-kernel+owner@opensuse.org

On Fri, Jul 13, 2012 at 02:17:30PM -0700, Linus Torvalds wrote:

On Fri, Jul 13, 2012 at 2:02 PM, Dave Jones wrote:

...

As long as you don't mind these being added after the fact, I suppose it would be workable. The reason I say that is sometimes, it even catches *us* by surprise. We recently found out our virtualisation guys started using sch_htb for example, and we inadvertantly broke it when we moved its module to a 'not always installed' kernel subpackage. (and before that, 9PFS..)

People don't tell us anything, but somehow expect things to keep working.

I think even a "educated guess" config file is better than what we have now.

The *two* requirements (and they're really the same theme) I personally think we should have for this are

- I think every single "select" for these things should come with a comment about what it is about and why the distro needs it (to show there was some thought involved and not just a blind "took it from the distro config")

- It should be about *minimal* settings. I'd rather have too few things and the occasional complaint about "oh, it didn't work because it missed XYZ" than have it grow to contain all the options just because somebody decided to just add random things until things worked.

I'd agree that should be the goal. It seems like something worth at least trying to get to. Even if we don't wind up merging them into the kernel, it will at least lead to a better documented distro config for every one that tries it. josh -- To unsubscribe, e-mail: opensuse-kernel+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-kernel+owner@opensuse.org

On Thu, Jul 19, 2012 at 8:26 AM, Steven Rostedt wrote:

Side note, and this is for the 1%. If you want a true minconfig for your system, ktest can do that for you.

Try it, it's actually much harder than it seems. Like allmodconfig, it handles the minimum hardware well, but it tends to handle the subtle issues really badly. Many config options cause *very* subtle failures that are almost impossible to see. Like firewalls not loading correctly (and leaving the machine completely open), or just stuff that you didn't happen to test (USB sticks, printers, certain programs) not working. Not having the right audit options will make things still "work", but you'll get warnings at bootup, and who knows what that causes etc etc. These kinds of things are exactly why I'd like to have a distro config. Linus -- To unsubscribe, e-mail: opensuse-kernel+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-kernel+owner@opensuse.org

On Thu, Jul 19, 2012 at 11:26:18AM -0400, Steven Rostedt wrote:

On Fri, Jul 13, 2012 at 02:17:30PM -0700, Linus Torvalds wrote:

...

The *two* requirements (and they're really the same theme) I personally think we should have for this are

- I think every single "select" for these things should come with a comment about what it is about and why the distro needs it (to show there was some thought involved and not just a blind "took it from the distro config")

What about expanding on Alan's idea. I'm guessing that 99% of the users build the kernel for the box that they are running. If this is the case, perhaps we can get the distros to add a:

/usr/share/Linux/Kconfig

And this Kconfig would have something like:

bool "Distro X config" select A select B select C [...]

Perhaps with a comment for each select. Or have the comments in the help section.

Then have the kernel kbuild system check if this file exists and include it.

Of course the kbuild system would need to verify that the selects exist, and perhaps warn if they do not. But the nice thing about this is that you would get the minconfig for the system you are running. When the system is updated to a new version, the minconfig would be updated too. The list of selects would not have to live in the kernel, nor would the kernel need to maintain the list for N+1 different distributions.

Is there a reason you don't want distro maintainers to maintain these files in the upstream git tree? (You said "the kernel need to maintain", but I would expect the distro maintainers to be doing that work.) I think it would actually be beneficial to maintain them upstream instead of in distro kernel packaging. You'd be able to track the history of changes with git. You would see for a given kernel version what options are set for each distro (e.g. F17 can support NEW_FOO_THING but F16 userspace can't so it doesn't select that). Perhaps most importantly, it provides a consolidated view of what options various distros are setting and allows the distro maintainers to easily do comparisons. josh -- To unsubscribe, e-mail: opensuse-kernel+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-kernel+owner@opensuse.org

On Thu, Jul 19, 2012 at 12:08:08PM -0400, Steven Rostedt wrote:

On Thu, 2012-07-19 at 11:45 -0400, Josh Boyer wrote:

...

Of course the kbuild system would need to verify that the selects exist,

...

and perhaps warn if they do not. But the nice thing about this is that you would get the minconfig for the system you are running. When the system is updated to a new version, the minconfig would be updated too. The list of selects would not have to live in the kernel, nor would the kernel need to maintain the list for N+1 different distributions.

Is there a reason you don't want distro maintainers to maintain these files in the upstream git tree? (You said "the kernel need to maintain", but I would expect the distro maintainers to be doing that work.)

I think it would actually be beneficial to maintain them upstream instead of in distro kernel packaging. You'd be able to track the history of changes with git. You would see for a given kernel version what options are set for each distro (e.g. F17 can support NEW_FOO_THING but F16 userspace can't so it doesn't select that). Perhaps most importantly, it provides a consolidated view of what options various distros are setting and allows the distro maintainers to easily do comparisons.

Then we'll have a list of options in each kernel:

Fedora 16 Fedora 17 Fedora 18 [...] Debian x Debian x+1 Debian x+2 [...] Ubuntu y Ubuntu y+1 [...]

Well, yes. I was thinking it would be more like: distro/Kconfig.fedora menuconfig FEDORA if FEDORA config FEDORA_16 select WHATEVER config FEDORA_17 ... distro/Kconfig.debian menuconfig DEBIAN if DEBIAN config DEBIAN_X ... etc. Not one giant distro file with a bunch of varying distros doing a bunch of selects. But in general, yes there would be options for each supported distro release.

What about older kernels? Say you installed Fedora 18 with an older kernel that doesn't know what to select? Having the distro tell the kernel what it needs seems to me the easiest for the 99% case.

How is the above not telling the kernel what it needs? I'm confused how the location of such a file makes it's functionality and usefulness differ... Quite possible I missed what you meant originally, but it sounds like we're talking about the same thing? Also, I'm not very convinced the 99% are going to be wanting to install shiny new versions of a distro with a kernel older than what the distro ships with. I could be very wrong, but it seems like in-general the whole premise of this RFC was geared towards using new kernels on distros.

Also, if something isn't supported by the older kernel, it would warn the user about it. That way the user can be told that their older kernel won't work with this version of the distro. And there wont be as many surprises. If the user is told "your init wont work with this kernel" before they compile it, then they shouldn't complain if they decide to install this older kernel and their box doesn't boot.

kconfig already spits out warnings for symbols being selected that don't exist. josh -- To unsubscribe, e-mail: opensuse-kernel+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-kernel+owner@opensuse.org

On Thu, Jul 19, 2012 at 06:30:47PM +0100, Alan Cox wrote:

...

Well, yes. I was thinking it would be more like:

distro/Kconfig.fedora menuconfig FEDORA if FEDORA config FEDORA_16 select WHATEVER config FEDORA_17

Nope you need

distro/everyarchtheyship/everykernelvarianttkeyship(smp,largemem,arm boards)/Kconfig

which for some distros is over 20 per release and the end user wouldn't have a cat in hells chance of knowing which to pick.

I wasn't include arch-specific options in the "minimal distro config" stuff. That doesn't seem minimal to me. I was thinking more along the lines of "distro X needs CGROUPS, SELINUX, HOTPLUG, DEVTMPFS, namespace stuff". Stuff that they need that is basically architecture independent that the distro userspace needs. Having the distro provide files that select architecture specific options and variations of that really doesn't seem any better than what most of them do already, which is just ship the whole damn config file in /boot (or some other location).

For the end user case you need the distro to plonk the right file in the right place and be done with it, once they do that the rest is bikeshedding a ten line Makefile rule.

If people want the distros to plonk some architecture+distro specific minimal config file down as part of the packaging, I guess that's a thing that could be done. I'd honestly wonder if maintaining X number of those in the packaging is something the distro maintainers would really like to do, but one can always hope. josh -- To unsubscribe, e-mail: opensuse-kernel+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-kernel+owner@opensuse.org

On Thu, 19 Jul 2012, Ben Hutchings wrote:

On Thu, Jul 19, 2012 at 06:30:47PM +0100, Alan Cox wrote:

...

For the end user case you need the distro to plonk the right file in the right place and be done with it, once they do that the rest is bikeshedding a ten line Makefile rule.

This might work well for future releases; is there not a need to make this work for past releases too?

This approach can work for any 3.x kernel version with any distro. The distro provides the file, with a new kernel version you do "make distconfig', with something prior to when this is added you do 'cp /etc/kconfig/filename .config ; make oldconfig' instead. the make oldconfig papers over a LOT of differences between the kernel that the distro built with and the kernel the user is trying to compile. David Lang -- To unsubscribe, e-mail: opensuse-kernel+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-kernel+owner@opensuse.org

...

kconfig already spits out warnings for symbols being selected that don't exist.

We can make these even bigger :-) Add lots of stars (*) around them!

Make oldconfig already handles this just fine Alan -- To unsubscribe, e-mail: opensuse-kernel+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-kernel+owner@opensuse.org

On Thu, 2012-07-19 at 13:56 -0400, Josh Boyer wrote:

Distros aren't stationary things.

Exactly my point.

I mean, some of them certainly aim for that goal, but userspace and kernels get upgraded all the time. So if this distro-Kconfig file is provided by some package _other_ than the kernel the distros are going to have a bit of a hassle keeping track of it.

How about a directory called /usr/share/Linux/Kconfig.d/ Then have anything installed that needs to work correctly put in its minimum (must have) requirement configs of the kernel. Say you are running Debian, and decide to try out systemd. If you set up your system to run that it would add a file called: /usr/share/Linux/Kconfig.d/systemd.conf or something, and this would select things like CGROUPS and the like. We could make the kernel build select all, or individual files in this directory. All for the 'make my distro work' or individual for a 'I want part of my distro to work' option.

Upgraded the kernel within the confines of that distro, right? So you go back to what was already installed and working. You don't go back arbitrarily far just to see what happens. I would think a reasonably crafted distro config would work in those scenarios.

A reasonable one, but still not the minimum. One issue with Linus's proposal is that he's asking us to focus on the 99%. But the 99% of who? Because 99% of Linux users do not compile their own kernels, so he must be asking about the 99% of Linux users that compile their own kernels. This 99% does not just simply compile their kernels, but only want to compile the absolutely necessary stuff. That is, they want their kernels not to include anything they are not using. A reasonable config would probably need to include a lot that's not used. -- Steve -- To unsubscribe, e-mail: opensuse-kernel+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-kernel+owner@opensuse.org

On Thu, 19 Jul 2012, Josh Boyer wrote:

On Thu, Jul 19, 2012 at 02:13:40PM -0400, Steven Rostedt wrote:

...

On Thu, 2012-07-19 at 13:56 -0400, Josh Boyer wrote:

...

Distros aren't stationary things.

Exactly my point.

...

I mean, some of them certainly aim for that goal, but userspace and kernels get upgraded all the time. So if this distro-Kconfig file is provided by some package _other_ than the kernel the distros are going to have a bit of a hassle keeping track of it.

How about a directory called /usr/share/Linux/Kconfig.d/

Then have anything installed that needs to work correctly put in its minimum (must have) requirement configs of the kernel.

Say you are running Debian, and decide to try out systemd. If you set up your system to run that it would add a file called:

/usr/share/Linux/Kconfig.d/systemd.conf

or something, and this would select things like CGROUPS and the like. We could make the kernel build select all, or individual files in this directory. All for the 'make my distro work' or individual for a 'I want part of my distro to work' option.

That sounds like a pretty good idea, aside from the fact that now your config is determined by 1) what is currently installed on your system and 2) people that don't maintain the kernel.

1 is obviously a great thing once you have a stable working set of packages you use daily, but wouldn't it kind of suck to have to rebuild the kernel just to install some new package? I mean... say you wanted to now use an NFS mount, but you didn't have nfs-utils previously installed. So you install it, and it plops the kconfig file in /usr/share but oops, you have to rebuild the kernel and reboot because that module isn't built. Of course I'm extrapolating possibly the worst usage case here, but it will still happen.

the alturnative to this is what? compile everything just in case you need it some time in the future? we already have some tools (vmware) that check for the proper kernel config when they startup, and if the appropriate stuff isn't there they ask for the root password and compile the modules.

2... yeah. I don't really know if that is going to pan out, but I am ever hopeful. I'd be mostly concerned with people that are coding userspace applications using every whiz-bang kernel feature. Or not paying attention at all to the kernel after the initial file creation and the options going stale (don't follow renames, etc).

it would be determined by the distro maintainers who maintain the kernel config for that distro. David Lang -- To unsubscribe, e-mail: opensuse-kernel+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-kernel+owner@opensuse.org

On Thu, 2012-07-19 at 18:35 -0400, Josh Boyer wrote:

...

...

2... yeah. I don't really know if that is going to pan out, but I am ever hopeful. I'd be mostly concerned with people that are coding userspace applications using every whiz-bang kernel feature. Or not paying attention at all to the kernel after the initial file creation and the options going stale (don't follow renames, etc).

it would be determined by the distro maintainers who maintain the kernel config for that distro.

Erm... not in Steven's scheme. At least I don't think distro kernel maintainers are going to willingly crawl through every application package that might depend on a kernel feature being enabled and maintain those files across X number of packages.

Correct. If we keep the selects in the kernel proper, then it would be the kernel maintainer to make sure it works for the necessary applications. If we have a directory called /usr/share/Linux/Kconfig.d/ then the individual packages could add their needed selects. Now this wouldn't be for the average package. We don't need emacs developers adding any configs here. It's just for those packages that are already tightly coupled with the kernel (systemd, iptables, SELinux tools, etc). -- Steve -- To unsubscribe, e-mail: opensuse-kernel+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-kernel+owner@opensuse.org

On Thu, 2012-07-19 at 13:19 -0400, Josh Boyer wrote:

kconfig already spits out warnings for symbols being selected that don't exist.

Does it? Since when does it do that? Or do you mean select in a more general way (not just meaning Kconfig's "select" statement)? Paul Bolle -- To unsubscribe, e-mail: opensuse-kernel+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-kernel+owner@opensuse.org

On Thu, Jul 19, 2012 at 8:22 PM, Josh Boyer wrote:

On Thu, Jul 19, 2012 at 08:20:36PM +0200, Paul Bolle wrote:

...

On Thu, 2012-07-19 at 13:19 -0400, Josh Boyer wrote:

...

kconfig already spits out warnings for symbols being selected that don't exist.

...

Does it? Since when does it do that? Or do you mean select in a more general way (not just meaning Kconfig's "select" statement)?

I believe Alan was more correct than me when he said it was 'make oldconfig' that produced the warnings.

Kconfig does spit out warnings for selecting things with unmet dependencies. But does anyone care? [...checking logs...] Oh, only 12 warnings in the v3.5-rc7 builds. Not that bad as my gut feeling said... warning: (ETRAX_USB_HOST && MOUSE_APPLETOUCH && MOUSE_BCM5974 && MOUSE_SYNAPTICS_USB && JOYSTICK_XPAD && TABLET_USB_ACECAD && TABLET_USB_AIPTEK && TABLET_USB_HANWANG && TABLET_USB_KBTAB && TABLET_USB_WACOM && TOUCHSCREEN_USB_COMPOSITE && INPUT_ATI_REMOTE2 && INPUT_KEYSPAN_REMOTE && INPUT_POWERMATE && INPUT_YEALINK && INPUT_CM109) selects USB which has unmet direct dependencies (USB_SUPPORT && USB_ARCH_HAS_HCD): 10 warnings in 2 logs warning: (IWLWIFI && IWLEGACY && ATH5K && ATH9K && ATH9K_HTC && CARL9170_LEDS) selects MAC80211_LEDS which has unmet direct dependencies (NET && WIRELESS && MAC80211 && LEDS_CLASS): 10 warnings in 2 logs warning: (LOCKDEP && FAULT_INJECTION_STACKTRACE_FILTER && LATENCYTOP && KMEMCHECK) selects FRAME_POINTER which has unmet direct dependencies (DEBUG_KERNEL && (CRIS || M68K || FRV || UML || AVR32 || SUPERH || BLACKFIN || MN10300) || ARCH_WANT_FRAME_POINTERS): 10 warnings in 2 logs warning: (MPC836x_RDK && MTD_NAND_FSL_ELBC && MTD_NAND_FSL_UPM) selects FSL_LBC which has unmet direct dependencies (FSL_SOC): 9 warnings in 2 logs warning: (SINGLE_MEMORY_CHUNK) selects NEED_MULTIPLE_NODES which has unmet direct dependencies (DISCONTIGMEM || NUMA): 9 warnings in 2 logs warning: (COMPAT) selects COMPAT_BINFMT_ELF which has unmet direct dependencies (COMPAT && BINFMT_ELF): 3 warnings in 1 logs warning: (DRM) selects DMA_SHARED_BUFFER which has unmet direct dependencies (EXPERIMENTAL): 3 warnings in 1 logs warning: (DRM_RADEON_KMS && DRM_I915 && STUB_POULSBO && FB_BACKLIGHT && USB_APPLEDISPLAY && FB_OLPC_DCON && ASUS_LAPTOP && SONY_LAPTOP && THINKPAD_ACPI && EEEPC_LAPTOP && ACPI_CMPC && SAMSUNG_Q10 && APPLE_GMUX) selects BACKLIGHT_CLASS_DEVICE which has unmet direct dependencies (HAS_IOMEM && BACKLIGHT_LCD_SUPPORT): 3 warnings in 1 logs warning: (IA64) selects PM which has unmet direct dependencies (PM_SLEEP || PM_RUNTIME): 4 warnings in 1 logs warning: (MOUSE_APPLETOUCH && MOUSE_BCM5974 && MOUSE_SYNAPTICS_USB && JOYSTICK_XPAD && TABLET_USB_ACECAD && TABLET_USB_AIPTEK && TABLET_USB_HANWANG && TABLET_USB_KBTAB && TABLET_USB_WACOM && TOUCHSCREEN_USB_COMPOSITE && INPUT_ATI_REMOTE2 && INPUT_KEYSPAN_REMOTE && INPUT_POWERMATE && INPUT_YEALINK && INPUT_CM109 && RC_ATI_REMOTE && IR_IMON && IR_MCEUSB && IR_REDRAT3 && IR_STREAMZAP && DRM_USB) selects USB which has unmet direct dependencies (USB_SUPPORT && USB_ARCH_HAS_HCD): 5 warnings in 1 logs warning: (PLATFORM_AT32AP) selects HAVE_NET_MACB which has unmet direct dependencies (NETDEVICES && ETHERNET): 3 warnings in 1 logs warning: (PREEMPT && DEBUG_ATOMIC_SLEEP) selects PREEMPT_COUNT which has unmet direct dependencies (COLDFIRE): 5 warnings in 1 logs Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds -- To unsubscribe, e-mail: opensuse-kernel+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-kernel+owner@opensuse.org

On Thu, Jul 19, 2012 at 8:22 PM, Josh Boyer wrote:

On Thu, Jul 19, 2012 at 08:20:36PM +0200, Paul Bolle wrote:

...

On Thu, 2012-07-19 at 13:19 -0400, Josh Boyer wrote:

...

kconfig already spits out warnings for symbols being selected that don't exist.

Does it? Since when does it do that? Or do you mean select in a more general way (not just meaning Kconfig's "select" statement)?

I believe Alan was more correct than me when he said it was 'make oldconfig' that produced the warnings.

Indeed, no warnings for all these remaining "select MISC_DEVICES" (patch sent to remove these). Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds -- To unsubscribe, e-mail: opensuse-kernel+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-kernel+owner@opensuse.org

On Fri, 2012-07-13 at 17:02 -0400, Dave Jones wrote:

I wish defconfig was actually something useful like this, instead of.. what the hell is it exactly ? No-one even seems to agree, other than "random selection of options, many of which were removed n years ago"

As for the "many of which were removed n years ago" part: in https://lkml.org/lkml/2011/11/18/211 I suggested to delete almost 2000 lines from over 400 defconfig files. That would have deleted all certainly unused macros from all defconfig files. Nothing happened after that. My fault, I'm afraid. But just removing all the certainly unused macros probably wouldn't have made a noticeable difference to anyone using those defconfig files anyway. Paul Bolle -- To unsubscribe, e-mail: opensuse-kernel+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-kernel+owner@opensuse.org

I always thought that the x86 defconfig file was the one that Linus used for his primary machine. -Tony -- To unsubscribe, e-mail: opensuse-kernel+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-kernel+owner@opensuse.org

On 07/13/12 14:55, Dave Jones wrote:

On Fri, Jul 13, 2012 at 11:50:25PM +0200, Paul Bolle wrote:

...

But just removing all the certainly unused macros probably wouldn't have made a noticeable difference to anyone using those defconfig files anyway.

My point is that I don't think there's many people actually using them. (maybe more on the niche platforms, but x86[64] ? I'm sceptical they're used at all)

I'm one of those people who use default configs. I build a given kernel version for many different embedded boards and expect the default config to work for them. It makes life much easier. I also share Linus' pain when building for my host x86 system and try to remove the cruft from my distro config. -Frank -- To unsubscribe, e-mail: opensuse-kernel+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-kernel+owner@opensuse.org

On Fri, 13 Jul 2012, Linus Torvalds wrote:

On Fri, Jul 13, 2012 at 2:17 PM, Casey Schaufler wrote:

...

Oh dear. I would expect Fedora to say that they require SELinux, thereby making it unusable by anyone doing LSM development.

Oh, *absolutely*.

These options would *not* be meant for people doing odd things and experienting with configs.

If you do that, then you might *start* by saying "I want this distro" to get the initial guesstimate of the config file you want, but then edit the .config by hand later (and remove the "I want all the Fedora requirements" option, of course).

This is explicitly and exclusively for normal users. The whole point of "expert configurator for special cases" should not be given any thought at all - those kinds of people should simply answer "No" to the "Do you want the distro basic kconfig requirements" question.

hopefully this can be made a little easier. more of a 'enable anything set in this file, then give me control again so I can turn things off' rather than having to manually edit the .config file. If this is done as a hard set of dependancy settings, it will be very annoying for people who for any reason want to disable something that the distro considers 'essential'. I also _really_ like the idea of being able to have a vmware option that enables the minimum devices that are needed to run. Having these be hard dependancies also seems like it would make interactions between these sorts of things much more likely to cause problems. If however they are one-shot "go through this file and enable anything that it says to turn on" things that then let you turn anything off, it seems much less likely to cause problems. and if we can then get some of the big hardware vendors to create such files to enable all the drivers needed for their hardware.... (the big things are easy, it's when you get into the internal monitoring busses and so on that things get messy) David Lang -- To unsubscribe, e-mail: opensuse-kernel+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-kernel+owner@opensuse.org

On Sat, Jul 14, 2012 at 12:33:51AM +0200, Jesper Juhl wrote:

How about we start cutting down on the options and start saying "a Linux system will provide feature x and y - always ...". Stuff like (and I'm just pulling random stuff out here) - ASLR, seccomp, 250HZ minimum etc etc.. We could cut the KConfig options down to 10% of what they are now if we just made a few (hard) choices about some things that would always be there that everyone could count on. If people want to deviate from the default minimum, sure, let them, but put it under *custom*, *embedded*, *specialized distro*, *you know what you are doing* menu options.

In number of options the "infrastructure" options are at most 20% of the total. The other 80% are individual drivers, hardware (like network cards, serial devices, usb devices, video...) or software (crypto algorithms, partition formats, codepages, filesystems...). You're going to have a hard time slashing 90% of that. OG. -- To unsubscribe, e-mail: opensuse-kernel+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-kernel+owner@opensuse.org

On Sat, Jul 14, 2012 at 12:18 AM, Ben Hutchings wrote:

...

- distro/Kconfig:

config DISTRO_REQUIREMENTS bool "Pick minimal distribution requirements"

choice DISTRO prompt "Distribution" depends on DISTRO_REQUIREMENTS

config FEDORA config OPENSUSE config UBUNTU ...

endchoice

and then depending on the DISTRO config, we'd include one of the distro-specific ones with lists of supported distro versions and then the random config settings for that version:

You might also want to *un*select some options like CONFIG_SYSFS_DEPRECATED and CONFIG_SYSFS_DEPRECATED_V2 that need to be set one way or the other depending on the version of udev. (I think it's possible to kluge this with the addition of a hidden negative config option.)

How about stuff like NET and INET, that every distro will need and yet is configurable even without EXPERT?

Yeah, I'm sure once distro configs are created we'll find quite a bit similarity in them. We could create Kconfig.distro that has all the common options selected and then have the per distro Kconfig files select that. Sure we'd need to watch Kconfig.distro (or Kconfig.min-distro) for changes, but I'd hope the distro maintainers would sign up to maintain these things upstream and be keeping an eye on it anyway. josh -- To unsubscribe, e-mail: opensuse-kernel+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-kernel+owner@opensuse.org