Source: linux Version: 5.2.6-1 Tags: patch X-Debbugs-CC: Benjamin Poirier <benjamin.poir...@gmail.com>,Michael Jeanson <mjean...@debian.org>
As reported in originally https://bugs.debian.org/948257#88 with the recent kmod update an issue with our signed packages was uncovered: On Wed, Jan 08, 2020 at 01:45:21PM +0100, Salvatore Bonaccorso wrote: > Hi Benjamin, > > On Wed, Jan 08, 2020 at 01:07:20PM +0100, Salvatore Bonaccorso wrote: > > Hi Benjamin, > > > > On Wed, Jan 08, 2020 at 09:24:30AM +0900, Benjamin Poirier wrote: > > [...] > > > Looks like the modules are built before lttng-sessiond is started: > > > Setting up lttng-modules-dkms (2.11.0-2) ... > > > Loading new lttng-modules-2.11.0 DKMS files... > > > Building for 5.4.0-2-amd64 > > > Building initial module for 5.4.0-2-amd64 > > > Done. > > > > > > lttng-lib-ring-buffer.ko: > > > Running module version sanity check. > > > - Original module > > > - No original module exists within this kernel > > > - Installation > > > - Installing to /lib/modules/5.4.0-2-amd64/updates/dkms/ > > > > > > [...] > > > > > > depmod... > > > > > > DKMS: install completed. > > > Setting up linux-headers-5.4.0-2-amd64 (5.4.8-1) ... > > > /etc/kernel/header_postinst.d/dkms: > > > dkms: running auto installation service for kernel 5.4.0-2-amd64:. > > > Setting up sudo (1.8.29-1) ... > > > Setting up babeltrace (1.5.7-2) ... > > > Setting up liburcu6:amd64 (0.11.1-2) ... > > > Setting up linux-headers-amd64 (5.4.8-1) ... > > > Setting up liblttng-ctl0:amd64 (2.11.0-3) ... > > > Setting up lttng-tools (2.11.0-3) ... > > > > > > Still, it doesn't work. > > > > > > > Simply restarting the sessiond should fix this. > > > > > > I tried restarting lttng-sessiond or rebooting the machine but it was no > > > help, lttng-sessiond always reports: > > > Error: Failed to load kmod library resources > > > Warning: No kernel tracer available > > > > > > A quick look into the code shows that is: > > > src/bin/lttng-sessiond/modprobe.c > > > kmod_set_log_fn(*ctx, log_kmod, NULL); > > > ret = kmod_load_resources(*ctx); > > > if (ret < 0) { > > > ERR("Failed to load kmod library resources"); > > > goto error; > > > } > > > > > > I didn't dig into libkmod, but I noticed (using opensnoop.bt) the > > > following: > > > 8071 lttng-sessiond 2 0 > > > /lib/modules/5.4.0-2-amd64/modules.dep.bin > > > 8071 lttng-sessiond 2 0 > > > /lib/modules/5.4.0-2-amd64/modules.alias.bin > > > 8071 lttng-sessiond 2 0 > > > /lib/modules/5.4.0-2-amd64/modules.symbols.bin > > > 8071 lttng-sessiond 2 0 > > > /lib/modules/5.4.0-2-amd64/modules.builtin.alias.bin > > > > > > On another machine which I haven't yet updated and where lttng still > > > works, I see: > > > 193519 lttng-sessiond 2 0 > > > /lib/modules/5.4.0-1-amd64/modules.dep.bin > > > 193519 lttng-sessiond 2 0 > > > /lib/modules/5.4.0-1-amd64/modules.alias.bin > > > 193519 lttng-sessiond 2 0 > > > /lib/modules/5.4.0-1-amd64/modules.symbols.bin > > > 193519 lttng-sessiond 2 0 > > > /lib/modules/5.4.0-1-amd64/modules.builtin.bin > > > > > > Not sure if /lib/modules/5.4.0-2-amd64/modules.builtin.alias.bin is > > > relevant but it's an empty file... > > > > > > After downgrading libkmod2 from > > > Version: 26+20191223-1 > > > to > > > Version: 26-3 > > > the issue with lttng is no longer apparent: > > > root@vsid:/tmp# lttng list --kernel > > > Kernel events: > > > ------------- > > > asoc_snd_soc_bias_level_start (loglevel: TRACE_EMERG (0)) (type: > > > tracepoint) > > > asoc_snd_soc_bias_level_done (loglevel: TRACE_EMERG (0)) (type: > > > tracepoint) > > > asoc_snd_soc_dapm_start (loglevel: TRACE_EMERG (0)) (type: > > > tracepoint) > > > [...] > > > > > > > Should we track this in a separate bug from #948257? > > So here is what I think is part of what is going on (unless there is > something broken in my analysis): > > Since 898490c010b5 ("moduleparam: Save information about built-in > modules in separate file")[1] which is in 5.2-rc1, there is a new > modules.builtin.modinfo provided. > > [1]: <https://git.kernel.org/linus/898490c010b5d2e499e03b7e815fc214209ac583> > > This one is installed in the -unsigned binary packages but not copied > over into the signing template, so the signed linux image packages do > not contain it. > > Now with kmod/26+20191223-1 we have 60084cf1cb24 ("libkmod: Add parser > for modules.builtin.modinfo")[2] adding the parser and [3] and [4] > using that. > > [2]: > <https://git.kernel.org/pub/scm/utils/kernel/kmod/kmod.git/commit/?id=60084cf1cb24dc3a257976c0d539a4c3ffda5db5> > [3]: > <https://git.kernel.org/pub/scm/utils/kernel/kmod/kmod.git/commit/?id=73eed2aba3cbe18bbda40f18f7bc32e8de1ec81f> > [4]: > <https://git.kernel.org/pub/scm/utils/kernel/kmod/kmod.git/commit/?id=b866b2165ae6cf18fb26b635f4a7ee57c0334731> Merge request: https://salsa.debian.org/kernel-team/linux/merge_requests/201 Regards, Salvatore
