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Are they going to build all the supported HW device drivers all into the kernel image? Serial Drivers, all the USB related drivers, all the printers, networks

by tkinom 12y ago

Are they going to build all the supported HW device drivers all into the kernel image? Serial Drivers, all the USB related drivers, all the printers, networks card, graphics card driver? How big will the new kernel image be? It also make dev/debugging driver task much harder as it requires complete reboot system to test it. Also, what about FS? such as ZFS? Build in by default, disable by default, load and reboot different kernel everytime I need something?

_delirium 12y ago
OpenBSD strongly discourages non-default kernel configurations [1], so anything they consider supported is just compiled in to the default kernel. [1] http://www.openbsd.com/faq/faq5.html#Why http://www.openbsd.com/faq/faq5.html#Why
imanaccount247 12y ago
>Are they going to build all the supported HW device drivers all into the kernel image? They always have. No drivers were modules. Modules were just there because netbsd had them. Kernel modules were already not being used at all in OpenBSD, they are removing an unused "feature".
ChuckMcM 12y ago
> Are they going to build all the supported HW device > drivers all into the kernel image? Historically that was what the 'Generic' kernel was, something which would boot on any system. A typical system configuration would be to boot the generic kernel, edit the configuration file to select only those devices and features that were going to be used, config and then make that kernel. Then boot from the configured kernel from then on. There has been both a lot of research and debate about various 'microkernel' strategies where the core of the micro-kernel really only knows how to access the boot disk and load modules. Then as hardware is probed and discovered, modules to support that hardware is loaded. As a desktop machine kernel, micro-kernels allow for changes in the hardware configuration to occur fairly easily without a lot of user visible fuss. But they do leave open the vulnerability that the module system can be exploited. Server systems generally change less frequently and hardware changes beyond adding or removing a disk drive are often quite rare. Things are always trade-offs. I wonder if there is anyone doing mixed virtualization studies. Using a hypervisor that is locked down for the lower layer and then booting the "user" machine for interactive use. This is a very powerful architectural choice and was been used for decades in IBM's mainframe OS. Perhaps we'll see a consumer OS based on those principles at some point.
- imanaccount247 12y ago
  Modules have nothing to do with microkernels. A system like you are describing is still a monolithic kernel. It changes nothing about the behavior of the system, it just saves a couple of MB of RAM. A microkernel runs the drivers as separate userspace programs, there are no modules involved.
feld 12y ago
OpenBSD doesn't support ZFS or any exotic filesystems.
- tkinom 12y ago
  Wouldn't even just supporting samba, nfs alone without kernel module will make the kernel bigger than needed? Or does OpenBSD doesn't support those network fs neither? If smbd/nfsd build in by default, wouldn't a single kernel image with samba/nfs build-in to kernel by default trigger more attack vector/surface especially if I just want to run a simple LAMP stack? Sorry for the OpenBSD noob questions. I am just curious on tradeoff on the decision turn off the kernel module completely.
  - feld 12y ago
    I don't have an answer for this, but I believe they support nfs out of the box.
seryoiupfurds 12y ago
$ du -h /bsd 11.3M /bsd Interestingly, the ramdisk/recovery kernel with a bunch of shell utilities built in is only 8.7M. I guess it saves more space by omitting fancy graphics drivers than is taken up by the recovery tools.

by tkinom 12y ago

_delirium 12y ago

OpenBSD strongly discourages non-default kernel configurations [1], so anything they consider supported is just compiled in to the default kernel. [1] http://www.openbsd.com/faq/faq5.html#Why http://www.openbsd.com/faq/faq5.html#Why

imanaccount247 12y ago

>Are they going to build all the supported HW device drivers all into the kernel image? They always have. No drivers were modules. Modules were just there because netbsd had them. Kernel modules were already not being used at all in OpenBSD, they are removing an unused "feature".

ChuckMcM 12y ago

> Are they going to build all the supported HW device > drivers all into the kernel image? Historically that was what the 'Generic' kernel was, something which would boot on any system. A typical system configuration would be to boot the generic kernel, edit the configuration file to select only those devices and features that were going to be used, config and then make that kernel. Then boot from the configured kernel from then on. There has been both a lot of research and debate about various 'microkernel' strategies where the core of the micro-kernel really only knows how to access the boot disk and load modules. Then as hardware is probed and discovered, modules to support that hardware is loaded. As a desktop machine kernel, micro-kernels allow for changes in the hardware configuration to occur fairly easily without a lot of user visible fuss. But they do leave open the vulnerability that the module system can be exploited. Server systems generally change less frequently and hardware changes beyond adding or removing a disk drive are often quite rare. Things are always trade-offs. I wonder if there is anyone doing mixed virtualization studies. Using a hypervisor that is locked down for the lower layer and then booting the "user" machine for interactive use. This is a very powerful architectural choice and was been used for decades in IBM's mainframe OS. Perhaps we'll see a consumer OS based on those principles at some point.

imanaccount247 12y ago
Modules have nothing to do with microkernels. A system like you are describing is still a monolithic kernel. It changes nothing about the behavior of the system, it just saves a couple of MB of RAM. A microkernel runs the drivers as separate userspace programs, there are no modules involved.

feld 12y ago

OpenBSD doesn't support ZFS or any exotic filesystems.

tkinom 12y ago
Wouldn't even just supporting samba, nfs alone without kernel module will make the kernel bigger than needed? Or does OpenBSD doesn't support those network fs neither? If smbd/nfsd build in by default, wouldn't a single kernel image with samba/nfs build-in to kernel by default trigger more attack vector/surface especially if I just want to run a simple LAMP stack? Sorry for the OpenBSD noob questions. I am just curious on tradeoff on the decision turn off the kernel module completely.
- feld 12y ago
  I don't have an answer for this, but I believe they support nfs out of the box.

seryoiupfurds 12y ago

$ du -h /bsd 11.3M /bsd Interestingly, the ramdisk/recovery kernel with a bunch of shell utilities built in is only 8.7M. I guess it saves more space by omitting fancy graphics drivers than is taken up by the recovery tools.