I think I am misunderstanding something because the aliases visible through kmod_config_get_aliases don't look anything like the modaliases used by udev to match devices to modules. I have some concern that making the changes necessary to use kmod would result in the files/indexes being much larger to include all the extra values that are being left out, so I think the sysfs approach might be the better way to go. On Tue, Nov 15, 2022 at 12:40 PM Allen Webb <allenwebb@xxxxxxxxxx> wrote: > > When i get the modinfo for usbhid, there are no aliases listed: > ``` > localhost ~ # modinfo usbhid > name: usbhid > filename: (builtin) > author: Andreas Gal > author: Vojtech Pavlik > author: Jiri Kosina > description: USB HID core driver > file: drivers/hid/usbhid/usbhid > license: GPL > parm: quirks:Add/modify USB HID quirks by specifying > quirks=vendorID:productID:quirks where vendorID, productID, and quirks > are all in 0x-prefixed hex (array of charp) > parm: ignoreled:Autosuspend with active leds (uint) > parm: kbpoll:Polling interval of keyboards (uint) > parm: jspoll:Polling interval of joysticks (uint) > parm: mousepoll:Polling interval of mice (uint) > ``` > > bluetooth however has an alias listed: > ``` > localhost ~ # modinfo bluetooth > filename: > /lib/modules/5.10.154-20424-gea7532c123d8/kernel/net/bluetooth/bluetooth.ko.gz > author: Marcel Holtmann <marcel@xxxxxxxxxxxx> > description: Bluetooth Core ver 2.22 > version: 2.22 > license: GPL > alias: net-pf-31 > vermagic: 5.10.154-20424-gea7532c123d8 SMP preempt mod_unload > name: bluetooth > intree: Y > retpoline: Y > depends: ecdh_generic > srcversion: F8E46CD048C50B0AA1CD471 > parm: disable_esco:Disable eSCO connection creation (bool) > parm: enable_ecred:Enable enhanced credit flow control mode (bool) > parm: disable_ertm:Disable enhanced retransmission mode (bool) > ``` > > I believe the reason for this is many modules use `#define > MODULE_DEVICE_TABLE(type, name)` which is a noop for buildin modules. > I have a local patch that resolves that issue here: > See: https://chromium-review.googlesource.com/c/chromiumos/third_party/kernel/+/3840672/1/include/linux/module.h#b246 > > However, I probably ought to rework that patch to create the > MODULE_ALIAS defines instead of the buildin.alias file. > > On Tue, Nov 15, 2022 at 11:35 AM Luis Chamberlain <mcgrof@xxxxxxxxxx> wrote: > > > > On Tue, Nov 15, 2022 at 10:05:35AM -0600, Allen Webb wrote: > > > On Mon, Nov 14, 2022 at 11:22 AM Lucas De Marchi > > > <lucas.demarchi@xxxxxxxxx> wrote: > > > > > > > > On Mon, Nov 14, 2022 at 10:42:50AM -0600, Allen Webb wrote: > > > > >On Fri, Nov 11, 2022 at 12:29 PM Luis Chamberlain <mcgrof@xxxxxxxxxx> wrote: > > > > >> > > > > >> On Fri, Nov 11, 2022 at 09:28:52AM -0600, Allen Webb wrote: > > > > >> > USB devices support the authorized attribute which can be used by > > > > >> > user-space to implement trust-based systems for enabling USB devices. It > > > > >> > would be helpful when building these systems to be able to know in > > > > >> > advance which kernel drivers (or modules) are reachable from a > > > > >> > particular USB device. > > > > >> > > > > > >> > This information is readily available for external modules in > > > > >> > modules.alias. However, builtin kernel modules are not covered. This > > > > >> > patch adds a sys-fs attribute to both builtin and loaded modules > > > > >> > exposing the matching rules in the modalias format for integration > > > > >> > with tools like USBGuard. > > > > >> > > > > > >> > Signed-off-by: Allen Webb <allenwebb@xxxxxxxxxx> > > > > >> > > > > >> Thanks for the patch Allen! > > > > >> > > > > >> I'd rather have something generic though, and it would seem kmod [0] already > > > > >> does this, have you seen the kmod support for builtin.alias.bin > > > > >> > > > > >> Can't that be used? > > > > > > > > > >Probably, but I don't see the builtin.alias.bin in my build. Is it experimental? > > > > > > > > no. That is generated by depmod since v27 using modules.builtin.modinfo > > > > generated by the kernel build system. Highly recommend v30 though > > > > as there were fixes in v28 and v29 and some changes to speed up its > > > > generation/use in v30: See entries mentioning > > > > builtin.alias and bultin.modinfo in > > > > https://git.kernel.org/pub/scm/utils/kernel/kmod/kmod.git/tree/NEWS > > > > > > > > libkmod/modprobe/modinfo also have the corresponding changes to lookup that > > > > index when resolving aliases. > > > > > > I see the file but it is largely missing the aliases I am interested > > > in, so it looks like I might need to modify my patch that creates > > > buildin.alias to add the missing alias defines in the header along > > > with the other module metadata for builtin modules. Does this sound > > > right to you? > > > > Can you clarify what is missing and why? And an RFC is welcomed if it > > helps demonstrates what you mean. > > > > Luis
