> -----Original Message----- > From: Lucas De Marchi <lucas.de.marchi@xxxxxxxxx> > Sent: den 11 maj 2021 20:02 > To: Peter Kjellerstedt <peter.kjellerstedt@xxxxxxxx> > Cc: linux-modules <linux-modules@xxxxxxxxxxxxxxx> > Subject: Re: [PATCH] libkmod: Always search modules.builtin if no alias > has been found > > On Tue, May 11, 2021 at 9:58 AM Lucas De Marchi > <lucas.de.marchi@xxxxxxxxx> wrote: > > > > On Mon, May 10, 2021 at 6:55 AM Peter Kjellerstedt > > <peter.kjellerstedt@xxxxxxxx> wrote: > > > > > > > -----Original Message----- > > > > From: Lucas De Marchi <lucas.de.marchi@xxxxxxxxx> > > > > Sent: den 9 maj 2021 07:55 > > > > To: Peter Kjellerstedt <peter.kjellerstedt@xxxxxxxx> > > > > Cc: linux-modules <linux-modules@xxxxxxxxxxxxxxx>; Peter Kjellerstedt > > > > <peter.kjellerstedt@xxxxxxxx> > > > > Subject: Re: [PATCH] libkmod: Always search modules.builtin if no alias > > > > has been found > > > > > > > > On Tue, May 4, 2021 at 5:17 PM Peter Kjellerstedt <pkj@xxxxxxxx> wrote: > > > > > > > > > > Commit 89443220e broke the lookup for builtin modules. modules.builtin > > > > > was no longer searched if kmod_lookup_alias_from_kernel_builtin_file() > > > > > returned 0. > > > > > > > > > > Signed-off-by: Peter Kjellerstedt <peter.kjellerstedt@xxxxxxxx> > > > > > --- > > > > > > > > > > I do not know if this is the correct thing to do, or if the commit > > > > > message makes any sense. However, it solves the problem we were seeing. > > > > > We use fuse, which installs /etc/modules-load.d/fuse.conf to load the > > > > > fuse kernel module. However, we have fuse built-in. Normally, the > > > > > following can be seen in the log: > > > > > > > > > > systemd-modules-load[192]: Module 'fuse' is built in > > > > > > > > > > but after commit 89443220e, we instead got: > > > > > > > > > > systemd-modules-load[193]: Failed to find module 'fuse' > > > > > > > > > > //Peter > > > > > > > > > > libkmod/libkmod-module.c | 2 +- > > > > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > > > > > > > diff --git a/libkmod/libkmod-module.c b/libkmod/libkmod-module.c > > > > > index 76a6dc3..6720930 100644 > > > > > --- a/libkmod/libkmod-module.c > > > > > +++ b/libkmod/libkmod-module.c > > > > > @@ -577,7 +577,7 @@ KMOD_EXPORT int kmod_module_new_from_lookup(struct kmod_ctx *ctx, > > > > > > > > > > DBG(ctx, "lookup modules.builtin.modinfo %s\n", alias); > > > > > err = kmod_lookup_alias_from_kernel_builtin_file(ctx, alias, list); > > > > > - if (err == -ENOSYS) { > > > > > + if (err == 0 || err == -ENOSYS) { > > > > > > > > So in your case you do have modules.builtin.modinfo, but fuse doesn't > > > > show up there. On the other hand it is listed in modules.builtin. > > > > Does modules.builtin.info contain anything or is it an empty file? > > > > > > We have neither modules.builtin.modinfo nor modules.builtin.info. > > > A little googling turned out that modules.builtin.modinfo seems to have > > > been introduced in 5.2, but this product uses a 4.19 based kernel. > > > > ok, now I understood the entire context. So it seems the problem is > > not that we are missing the handling for return 0, but rather that > > kmod_lookup_alias_from_kernel_builtin_file() is not returning -ENOSYS > > when it should (index doesn't exist). I thought this was covered, but > > obviously I was wrong. I will take a look what's going on.... we > > should not handle err == 0 the same way we handle err == -ENOSYS. If > > the index is missing we want to fallback to the old one, but if the > > index is there and we didn't find the module, we should just return > > an error. > > Ok, I think I see what's happening. If you have a recent kmod with an > old kernel, you have this scenario: > > 1) modules.builtin.modinfo doesn't exist since kernel didn't create it > 2) depmod will write and empty index to modules.builtin.alias.bin when > modules.builtin.modinfo is not present > > I have a fix to depmod to stop writing an empty index. I will submit > that for review. I have tested the suggested solution and it solves the problem for us. Thank you. //Peter > thanks > Lucas De Marchi > > > > > > Lucas De Marchi > > > > > > > > > It seems to me something else is broken: all modules in > > > > modules.builtin should be in modules.builtin.modinfo as well. What > is > > > > the result of the following commands? > > > > > > > > grep fuse /lib/modules/$(uname -r)/modules.builtin > > > > > > kernel/fs/fuse/fuse.ko > > > > > > > grep fuse /lib/modules/$(uname -r)/modules.builtin.modinfo > > > > > > grep: /lib/modules/4.19.110-axis8/modules.builtin.modinfo: No such > file or directory > > > > > > This is an embedded product built with our own distribution based on > > > Poky Gatesgarth from the Yocto Project. The rootfs is read-only, > including > > > /lib/modules, so any contest there is created when the firmware image > is > > > built. > > > > > > > thanks > > > > Lucas De Marchi > > > > > > > > > /* Optional index missing, try the old one */ > > > > > DBG(ctx, "lookup modules.builtin %s\n", alias); > > > > > err = kmod_lookup_alias_from_builtin_file(ctx, > alias, list); > > > > > > //Peter > > >