On Tue, Mar 30, 2021 at 09:53:25AM +0000, Denis Osterland-Heim wrote: > Hi, > > Thanks for the input. > > >$(mod_strip_cmd) $(2)/$(notdir $@) ; \ > >$(mod_sign_cmd) $(2)/$(notdir $@) $(patsubst %,|| true,$(KBUILD_EXTMOD)) ; \ > from scripts/Makefile.modinst > > As far as I got it, with INSTALL_MOD_STRIP="--strip-debug -R > .GCC.command.line" in KERNEL_MAKE_OPT > and always strip=n in targetinstall it should work identically with signed > modules and without.
We should add TARGET_COMPILER_RECORD_SWITCHES to the kernel blacklist. Then .GCC.command.line won't show up at all. I've seen the kernel complain about it anyways, but I keep forgetting it. At that point only '--strip-debug' is necessary and that's the default, so INSTALL_MOD_STRIP=1 works too. And about always stripping: I think we should do this. In the past, we hat a separate debug nfsroot directory but that's long gone. And for kernel modules we don't actually keep a separate debug file. So we don't actually keep a unstripped version. So stripping early is fine. I think, the unstripped version remains in the build tree, so if someone needs the debug symbols, they can look there. > What do you and Marc think? I'm not a kernel developer, so Marc, does that make sense to you? Michael > Am Dienstag, den 30.03.2021, 09:53 +0200 schrieb Michael Olbrich: > > On Tue, Mar 30, 2021 at 06:08:10AM +0000, Denis Osterland-Heim wrote: > > > If CONFIG_MODULE_SIG_ALL is set in kernelconfig then modules will be > > > automatically signed during the modules_install phase of a kernel build. > > > > > > Signed modules are BRITTLE as the signature is outside of the defined ELF > > > container. Thus they MAY NOT be stripped once the signature is computed > > > and attached. Note the entire module is the signed payload, including any > > > and all debug information present at the time of signing. > > > > Hmm, we had the same issue at some point. The solution was a local copy of > > the shell code that does the stripping and installing. I think we added > > some code to sign the Modules again. > > The result was nice, but the whole thing was rather invasive and makes > > assumptions on how the module signing works internally in the kernel. > > So it was not something that I wanted to merge mainline that way. > > > > In general, I like this approach better. But there are two issues with it. > > > > 1. There are redundant options and if the uses gets it wrong then it wont > > fail at build time. We can get this from the kernelconfig: > > '$(shell ptxd_get_kconfig $(KERNEL_CONFIG) CONFIG_MODULE_SIG_ALL)' I think. > > But we have to make sure that it's not evaluated too early. To avoid > > slowing down ptxdist startup. > > > > 2. The modules are not stripped at all. So we should set > > INSTALL_MOD_STRIP=1 in this case. > > > > Marc, what do you think? > > > > Michael > > > > > See: > > > https://www.kernel.org/doc/html/latest/admin-guide/module-signing.html > > > Signed-off-by: Denis Osterland-Heim <denis.osterl...@diehl.com> > > > --- > > > platforms/kernel.in | 7 +++++++ > > > rules/kernel.make | 3 ++- > > > 2 files changed, 9 insertions(+), 1 deletion(-) > > > > > > diff --git a/platforms/kernel.in b/platforms/kernel.in > > > index 68899c0f7..8b9473b03 100644 > > > --- a/platforms/kernel.in > > > +++ b/platforms/kernel.in > > > @@ -32,6 +32,13 @@ config KERNEL_MODULES > > > default y > > > prompt "build kernel-modules" > > > > > > +config KERNEL_MODULES_SIGNED > > > +bool "kernel-modules are signed on install" > > > +depends on KERNEL_MODULES > > > +help > > > + Set this to y if CONFIG_MODULE_SIG_ALL is y in kernelconfig. > > > + Otherwise the strip would damage automatically generated signature. > > > + > > > config KERNEL_MODULES_INSTALL > > > bool > > > default y > > > diff --git a/rules/kernel.make b/rules/kernel.make > > > index ea748fc8a..c964bd672 100644 > > > --- a/rules/kernel.make > > > +++ b/rules/kernel.make > > > @@ -313,7 +313,8 @@ ifdef PTXCONF_KERNEL_MODULES_INSTALL > > > @$(call install_fixup, kernel-modules, AUTHOR,"Robert Schwebel > > > <r.schwe...@pengutronix.de>") > > > @$(call install_fixup, kernel-modules, DESCRIPTION,missing) > > > > > > -@$(call install_glob, kernel-modules, 0, 0, -, /lib/modules, *.ko,, k) > > > +@$(call install_glob, kernel-modules, 0, 0, -, /lib/modules, *.ko,, \ > > > +$(call ptx/ifdef,PTXCONF_KERNEL_MODULES_SIGNED,n,k)) > > > @$(call install_glob, kernel-modules, 0, 0, -, /lib/modules,, *.ko > > > */build */source, n) > > > > > > @$(call install_finish, kernel-modules) > > > -- > > > 2.31.1 > > > > > > _______________________________________________ > > > ptxdist mailing list > > > ptxdist@pengutronix.de > > > To unsubscribe, send a mail with subject "unsubscribe" to > > > ptxdist-requ...@pengutronix.de > Diehl Connectivity Solutions GmbH > Geschäftsführung: Horst Leonberger > Sitz der Gesellschaft: Nürnberg - Registergericht: Amtsgericht > Nürnberg: HRB 32315 > > ________________________________ > > Der Inhalt der vorstehenden E-Mail ist nicht rechtlich bindend. 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