On 04/11/25 4:47 pm, Samir M wrote:
Hello,
I am observing below error while running the make modules_install command on latest mainline kernel on IBM Power11 server.
Error: DEPMOD /lib/modules/6.18.0-rc4 depmod: ERROR: kmod_builtin_iter_next: unexpected string without modname prefix
IBM CI has also reported this error.
Error:
depmod: ERROR: kmod_builtin_iter_next: unexpected string without modname prefix INSTALL /boot depmod: ERROR: kmod_builtin_iter_next: unexpected string without modname prefix depmod: ERROR: kmod_builtin_iter_next: unexpected string without modname prefix
Git bisect is pointing to below commit as first bad commit.
d50f21091358b2b29dc06c2061106cdb0f030d03 is the first bad commit commit d50f21091358b2b29dc06c2061106cdb0f030d03 Author: Dimitri John Ledkov dimitri.ledkov@surgut.co.uk Date: Sun Oct 26 20:21:00 2025 +0000
kbuild: align modinfo section for Secureboot Authenticode EDK2 compat
Previously linker scripts would always generate vmlinuz that has sections aligned. And thus padded (correct Authenticode calculation) and unpadded calculation would be same. As in https://github.com/rhboot/pesign userspace tool would produce the same authenticode digest for both of the following commands:
pesign --padding --hash --in ./arch/x86_64/boot/bzImage pesign --nopadding --hash --in ./arch/x86_64/boot/bzImage
The commit 3e86e4d74c04 ("kbuild: keep .modinfo section in vmlinux.unstripped") added .modinfo section of variable length. Depending on kernel configuration it may or may not be aligned.
All userspace signing tooling correctly pads such section to calculation spec compliant authenticode digest.
However, if bzImage is not further processed and is attempted to be loaded directly by EDK2 firmware, it calculates unpadded Authenticode digest and fails to correct accept/reject such kernel builds even when propoer Authenticode values are enrolled in db/dbx. One can say EDK2 requires aligned/padded kernels in Secureboot.
Thus add ALIGN(8) to the .modinfo section, to esure kernels irrespective of modinfo contents can be loaded by all existing EDK2 firmware builds.
Fixes: 3e86e4d74c04 ("kbuild: keep .modinfo section in vmlinux.unstripped") Cc: stable@vger.kernel.org Signed-off-by: Dimitri John Ledkov dimitri.ledkov@surgut.co.uk Link: https://patch.msgid.link/20251026202100.679989-1-dimitri.ledkov@surgut.co.uk Signed-off-by: Nathan Chancellor nathan@kernel.org
include/asm-generic/vmlinux.lds.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
Git Bisect log:
git bisect log git bisect start # status: waiting for both good and bad commits # bad: [c9cfc122f03711a5124b4aafab3211cf4d35a2ac] Merge tag 'for-6.18-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux git bisect bad c9cfc122f03711a5124b4aafab3211cf4d35a2ac # status: waiting for good commit(s), bad commit known # good: [dcb6fa37fd7bc9c3d2b066329b0d27dedf8becaa] Linux 6.18-rc3 git bisect good dcb6fa37fd7bc9c3d2b066329b0d27dedf8becaa # good: [3ad81aa52085a7e67edfa4bc8f518e5962196bb3] Merge tag 'v6.18-p4' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 git bisect good 3ad81aa52085a7e67edfa4bc8f518e5962196bb3 # good: [f414f9fd68797182f8de4e1cd9855b6b28abde99] Merge tag 'pci-v6.18-fixes-4' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci git bisect good f414f9fd68797182f8de4e1cd9855b6b28abde99 # good: [41dacb39fe79cd2fce42d31fa6658d926489a548] Merge tag 'drm-xe-fixes-2025-10-30' of https://gitlab.freedesktop.org/drm/xe/kernel into drm-fixes git bisect good 41dacb39fe79cd2fce42d31fa6658d926489a548 # bad: [f9bc8e0912b8f6b1d60608a715a1da575670e038] Merge tag 'perf-urgent-2025-11-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip git bisect bad f9bc8e0912b8f6b1d60608a715a1da575670e038 # good: [c44b4b9eeb71f5b0b617abf6fd66d1ef0aab6200] objtool: Fix skip_alt_group() for non-alternative STAC/CLAC git bisect good c44b4b9eeb71f5b0b617abf6fd66d1ef0aab6200 # bad: [cb7f9fc3725a11447a4af69dfe8d648e4320acdc] Merge tag 'kbuild-fixes-6.18-2' of git://git.kernel.org/pub/scm/linux/kernel/git/kbuild/linux git bisect bad cb7f9fc3725a11447a4af69dfe8d648e4320acdc # bad: [d50f21091358b2b29dc06c2061106cdb0f030d03] kbuild: align modinfo section for Secureboot Authenticode EDK2 compat git bisect bad d50f21091358b2b29dc06c2061106cdb0f030d03 # good: [5ff90d427ef841fa48608d0c19a81c48d6126d46] kbuild: install-extmod-build: Fix when given dir outside the build dir git bisect good 5ff90d427ef841fa48608d0c19a81c48d6126d46 # first bad commit: [d50f21091358b2b29dc06c2061106cdb0f030d03] kbuild: align modinfo section for Secureboot Authenticode EDK2 compat
Please add below tag as well, if you happen to fix this.
Reported-by: Venkat Rao Bagalkote venkat88@linux.ibm.com
Regards,
Venkat.
If you happen to fix the above issue, then please add below tag. Reported-by: Samir M samir@linux.ibm.com
Regards, Samir.