Bug #1840704 “ZFS kernel modules lack debug symbols” : Bugs : linux package : Ubuntu

Mauricio Faria de Oliveira (mfo) on 2019-08-19

Changed in linux (Ubuntu):
status:	New → In Progress
assignee:	nobody → Mauricio Faria de Oliveira (mfo)

Mauricio Faria de Oliveira (mfo) on 2019-08-28

description:	updated
description:	updated

Revision history for this message

Mauricio Faria de Oliveira (mfo) wrote on 2019-08-28:

#1

Test Build 1) Old behavior

goal: show limitations/issues.

- original packaging
- zfs not built with debug symbols
- zfs modules not present in debug package
- extra modules lack .gnu_debuglink section

Original packaging:

There are no ZFS modules in the debug package:

$ dpkg-deb -x linux-image-unsigned-5.3.0-8-generic-dbgsym_5.3.0-8.9_amd64.ddeb ddeb-orig

$ ls ddeb-orig/usr/lib/debug/lib/modules/5.3.0-8-generic/kernel/zfs
...: No such file or directory

Accordingly, the ZFS modules are the only modules without '.gnu_debuglink' section in the 'linux-modules' package:

$ dpkg-deb -x linux-modules-5.3.0-8-generic_5.3.0-8.9_amd64.deb deb-modules

$ find deb-modules/ -name '*.ko' | while read ko; do objdump -h -j .gnu_debuglink $ko >/dev/null 2>&1 || echo "Module without debug link '$ko'"; done
Module without debug link 'deb-modules/lib/modules/5.3.0-8-generic/kernel/zfs/icp.ko'
Module without debug link 'deb-modules/lib/modules/5.3.0-8-generic/kernel/zfs/spl.ko'
Module without debug link 'deb-modules/lib/modules/5.3.0-8-generic/kernel/zfs/zavl.ko'
Module without debug link 'deb-modules/lib/modules/5.3.0-8-generic/kernel/zfs/zcommon.ko'
Module without debug link 'deb-modules/lib/modules/5.3.0-8-generic/kernel/zfs/zfs.ko'
Module without debug link 'deb-modules/lib/modules/5.3.0-8-generic/kernel/zfs/zlua.ko'
Module without debug link 'deb-modules/lib/modules/5.3.0-8-generic/kernel/zfs/znvpair.ko'
Module without debug link 'deb-modules/lib/modules/5.3.0-8-generic/kernel/zfs/zunicode.ko'

By the way, this is also the case for *all* modules in the 'linux-modules-extra' package:
(only modules in the 'linux-modules' package have '.gnu_debuglink' sections).

$ dpkg-deb -x linux-modules-extra-5.3.0-8-generic_5.3.0-8.9_amd64.deb deb-modules-extras

$ find deb-modules-extras/ -name '*.ko' | wc -l
4508

$ find deb-modules-extras/ -name '*.ko' | while read ko; do objdump -h -j .gnu_debuglink $ko >/dev/null 2>&1 || echo "Module without debug link '$ko'"; done | wc -l
4508

Test Build 1) Old behavior

goal: show limitations/issues.

- original packaging
- zfs not built with debug symbols
- zfs modules not present in debug package
- extra modules lack .gnu_debuglink section

Original packaging:

There are no ZFS modules in the debug package:

$ dpkg-deb -x linux-image-unsigned-5.3.0-8-generic-dbgsym_5.3.0-8.9_amd64.ddeb ddeb-orig

$ ls ddeb-orig/usr/lib/debug/lib/modules/5.3.0-8-generic/kernel/zfs
	...: No such file or directory

Accordingly, the ZFS modules are the only modules without '.gnu_debuglink' section in the 'linux-modules' package:

$ dpkg-deb -x linux-modules-5.3.0-8-generic_5.3.0-8.9_amd64.deb deb-modules

$ find deb-modules/ -name '*.ko' | while read ko; do objdump -h -j .gnu_debuglink $ko >/dev/null 2>&1 || echo "Module without debug link '$ko'"; done
	Module without debug link 'deb-modules/lib/modules/5.3.0-8-generic/kernel/zfs/icp.ko'
	Module without debug link 'deb-modules/lib/modules/5.3.0-8-generic/kernel/zfs/spl.ko'
	Module without debug link 'deb-modules/lib/modules/5.3.0-8-generic/kernel/zfs/zavl.ko'
	Module without debug link 'deb-modules/lib/modules/5.3.0-8-generic/kernel/zfs/zcommon.ko'
	Module without debug link 'deb-modules/lib/modules/5.3.0-8-generic/kernel/zfs/zfs.ko'
	Module without debug link 'deb-modules/lib/modules/5.3.0-8-generic/kernel/zfs/zlua.ko'
	Module without debug link 'deb-modules/lib/modules/5.3.0-8-generic/kernel/zfs/znvpair.ko'
	Module without debug link 'deb-modules/lib/modules/5.3.0-8-generic/kernel/zfs/zunicode.ko'

By the way, this is also the case for *all* modules in the 'linux-modules-extra' package:
(only modules in the 'linux-modules' package have '.gnu_debuglink' sections).

$ dpkg-deb -x linux-modules-extra-5.3.0-8-generic_5.3.0-8.9_amd64.deb deb-modules-extras

$ find deb-modules-extras/ -name '*.ko' | wc -l
	4508

$ find deb-modules-extras/ -name '*.ko' | while read ko; do objdump -h -j .gnu_debuglink $ko >/dev/null 2>&1 || echo "Module without debug link '$ko'"; done | wc -l
	4508

Revision history for this message

Mauricio Faria de Oliveira (mfo) wrote on 2019-08-28:

#2

Download full text (6.0 KiB)

Test Build 2) New behavior if ZFS modules are *not* built with debug symbols

goal: show failsafe/backwards compatible behavior if zfs-dksm doesn't support/build debug symbols
and kernel build log reports missing debug symbols, and extra modules have .gnu_debuglink.

- test packaging
- zfs not built with debug symbols (disabled manually in dkms-build if-check)
- zfs modules not present in debug package
- extra modules have .gnu_debuglink section
- (no regressions)

Test packaging, with debug symbols *not enabled* in zfs-dkms:

The debug symbols are not found (as expected),
and this case is handled without problems:

II: dkms-build installing zfs into /home/ubuntu/dbgsym/unstable/debian/linux-image-unsigned-5.3.0-8-generic-dbgsym/usr/lib/debug/lib/modules/5.3.0-8-generic/kernel/zfs (debug symbols)
ignoring zavl.ko (missing debug symbols)
stripping zavl.ko
ignoring znvpair.ko (missing debug symbols)
stripping znvpair.ko
ignoring zunicode.ko (missing debug symbols)
stripping zunicode.ko
ignoring zcommon.ko (missing debug symbols)
stripping zcommon.ko
ignoring zfs.ko (missing debug symbols)
stripping zfs.ko
ignoring icp.ko (missing debug symbols)
stripping icp.ko
ignoring zlua.ko (missing debug symbols)
stripping zlua.ko
ignoring spl.ko (missing debug symbols)
stripping spl.ko
II: dkms-build installing zfs into /home/ubuntu/dbgsym/unstable/debian/linux-modules-5.3.0-8-generic/lib/modules/5.3.0-8-generic/kernel/zfs
signing zavl.ko
signing znvpair.ko
signing zunicode.ko
signing zcommon.ko
signing zfs.ko
signing icp.ko
signing zlua.ko
signing spl.ko
II: dkms-build build zfs complete

The debug package contains the ZFS directory, but it's empty:

$ dpkg-deb -x linux-image-unsigned-5.3.0-8-generic-dbgsym_5.3.0-8.9_amd64.ddeb ddeb-test-disabled
$ ls ddeb-test-disabled/usr/lib/debug/lib/modules/5.3.0-8-generic/kernel/zfs/
$

The kernel build log documents which modules do not have debug symbols,
now covering modules built with DKMS (zfs and vbox):

$ grep WARNING build.log
echo "WARNING: Missing debug symbols for module '$module'."; \
WARNING: Missing debug symbols for module '/lib/modules/5.3.0-8-generic/kernel/zfs/zavl.ko'.
WARNING: Missing debug symbols for module '/lib/modules/5.3.0-8-generic/kernel/zfs/znvpair.ko'.
WARNING: Missing debug symbols for module '/lib/modules/5.3.0-8-generic/kernel/zfs/zunicode.ko'.
WARNING: Missing debug symbols for module '/lib/modules/5.3.0-8-generic/kernel/zfs/zcommon.ko'.
WARNING: Missing debug symbols for module '/lib/modules/5.3.0-8-generic/kernel/zfs/zfs.ko'.
WARNING: Missing debug symbols for module '/lib/modules/5.3.0-8-generic/kernel/zfs/icp.ko'.
WARNING: Missing debug symbols for module '/lib/modules/5.3.0-8-generic/kernel/zfs/zlua.ko'.
WARNING: Missing debug symbols for module '/lib/modules/5.3.0-8-generic/kernel/zfs/spl.ko'.
WARNING: Missing debug symbols for module '/lib/modules/5.3.0-8-generic/kernel/virtualbox-guest/vboxguest.ko'.
WARNING: Missing debug symbols for module '/lib/modules/5.3.0-8-generic/kernel/virtualbox-guest/vboxsf.ko'.

The ZFS modules have no '.gnu_debuglink' section or any other debug section (as expected):

$ dpkg-deb -x l...

Test Build 2) New behavior if ZFS modules are *not* built with debug symbols

goal: show failsafe/backwards compatible behavior if zfs-dksm doesn't support/build debug symbols
      and kernel build log reports missing debug symbols, and extra modules have .gnu_debuglink.

- test packaging
- zfs not built with debug symbols (disabled manually in dkms-build if-check)
- zfs modules not present in debug package
- extra modules have .gnu_debuglink section
- (no regressions)

Test packaging, with debug symbols *not enabled* in zfs-dkms:

The debug symbols are not found (as expected), 
	and this case is handled without problems:

II: dkms-build installing zfs into /home/ubuntu/dbgsym/unstable/debian/linux-image-unsigned-5.3.0-8-generic-dbgsym/usr/lib/debug/lib/modules/5.3.0-8-generic/kernel/zfs (debug symbols)
	ignoring zavl.ko (missing debug symbols)
	stripping zavl.ko
	ignoring znvpair.ko (missing debug symbols)
	stripping znvpair.ko
	ignoring zunicode.ko (missing debug symbols)
	stripping zunicode.ko
	ignoring zcommon.ko (missing debug symbols)
	stripping zcommon.ko
	ignoring zfs.ko (missing debug symbols)
	stripping zfs.ko
	ignoring icp.ko (missing debug symbols)
	stripping icp.ko
	ignoring zlua.ko (missing debug symbols)
	stripping zlua.ko
	ignoring spl.ko (missing debug symbols)
	stripping spl.ko
	II: dkms-build installing zfs into /home/ubuntu/dbgsym/unstable/debian/linux-modules-5.3.0-8-generic/lib/modules/5.3.0-8-generic/kernel/zfs
	signing zavl.ko
	signing znvpair.ko
	signing zunicode.ko
	signing zcommon.ko
	signing zfs.ko
	signing icp.ko
	signing zlua.ko
	signing spl.ko
	II: dkms-build build zfs complete

The debug package contains the ZFS directory, but it's empty:

$ dpkg-deb -x linux-image-unsigned-5.3.0-8-generic-dbgsym_5.3.0-8.9_amd64.ddeb ddeb-test-disabled
	$ ls ddeb-test-disabled/usr/lib/debug/lib/modules/5.3.0-8-generic/kernel/zfs/
	$

The kernel build log documents which modules do not have debug symbols,
now covering modules built with DKMS (zfs and vbox):

$ grep WARNING build.log 
		        echo "WARNING: Missing debug symbols for module '$module'."; \
	WARNING: Missing debug symbols for module '/lib/modules/5.3.0-8-generic/kernel/zfs/zavl.ko'.
	WARNING: Missing debug symbols for module '/lib/modules/5.3.0-8-generic/kernel/zfs/znvpair.ko'.
	WARNING: Missing debug symbols for module '/lib/modules/5.3.0-8-generic/kernel/zfs/zunicode.ko'.
	WARNING: Missing debug symbols for module '/lib/modules/5.3.0-8-generic/kernel/zfs/zcommon.ko'.
	WARNING: Missing debug symbols for module '/lib/modules/5.3.0-8-generic/kernel/zfs/zfs.ko'.
	WARNING: Missing debug symbols for module '/lib/modules/5.3.0-8-generic/kernel/zfs/icp.ko'.
	WARNING: Missing debug symbols for module '/lib/modules/5.3.0-8-generic/kernel/zfs/zlua.ko'.
	WARNING: Missing debug symbols for module '/lib/modules/5.3.0-8-generic/kernel/zfs/spl.ko'.
	WARNING: Missing debug symbols for module '/lib/modules/5.3.0-8-generic/kernel/virtualbox-guest/vboxguest.ko'.
	WARNING: Missing debug symbols for module '/lib/modules/5.3.0-8-generic/kernel/virtualbox-guest/vboxsf.ko'.

The ZFS modules have no '.gnu_debuglink' section or any other debug section (as expected):

$ dpkg-deb -x linux-modules-5.3.0-8-generic_5.3.0-8.9_amd64.deb deb-modules

$ find deb-modules/ -name '*.ko' | while read ko; do objdump -h -j .gnu_debuglink $ko >/dev/null 2>&1 || echo "Module without debug link '$ko'"; done
	Module without debug link 'deb-modules/lib/modules/5.3.0-8-generic/kernel/zfs/icp.ko'
	Module without debug link 'deb-modules/lib/modules/5.3.0-8-generic/kernel/zfs/spl.ko'
	Module without debug link 'deb-modules/lib/modules/5.3.0-8-generic/kernel/zfs/zavl.ko'
	Module without debug link 'deb-modules/lib/modules/5.3.0-8-generic/kernel/zfs/zcommon.ko'
	Module without debug link 'deb-modules/lib/modules/5.3.0-8-generic/kernel/zfs/zfs.ko'
	Module without debug link 'deb-modules/lib/modules/5.3.0-8-generic/kernel/zfs/zlua.ko'
	Module without debug link 'deb-modules/lib/modules/5.3.0-8-generic/kernel/zfs/znvpair.ko'
	Module without debug link 'deb-modules/lib/modules/5.3.0-8-generic/kernel/zfs/zunicode.ko'

$ for ko in deb-modules/lib/modules/5.3.0-8-generic/kernel/zfs/*.ko; do objdump -h $ko | grep debug; done
	$

But all modules in 'linux-modules-extra' now have '.gnu_debuglink' sections
(except virtualbox modules which are DKMS-built without debug symbols too.)

$ dpkg-deb -x linux-modules-extra-5.3.0-8-generic_5.3.0-8.9_amd64.deb deb-modules-extra

$ find deb-modules-extra/ -name '*.ko' | while read ko; do objdump -h -j .gnu_debuglink $ko >/dev/null 2>&1 || echo "Module without debug link '$ko'"; done
		Module without debug link 'deb-modules-extra/lib/modules/5.3.0-8-generic/kernel/virtualbox-guest/vboxguest.ko'
		Module without debug link 'deb-modules-extra/lib/modules/5.3.0-8-generic/kernel/virtualbox-guest/vboxsf.ko'

$ find deb-modules-extra/ -name '*.ko' | wc -l
	4508

The objdump disassembly is identical (no instruction changes expected from packaging-only changes)

build1 $ for ko in deb-modules/lib/modules/5.3.0-8-generic/kernel/zfs/*.ko; do objdump -d $ko > objdump_-d/$(basename $ko).log; done
	build2 $ for ko in deb-modules/lib/modules/5.3.0-8-generic/kernel/zfs/*.ko; do objdump -d $ko > objdump_-d/$(basename $ko).log; done

$ diff -ur build1/objdump_-d/ build2/objdump_-d/
	$

All 'objdump -d' files are definitely non-empty:

$ wc -l build1/objdump_-d/* build2/objdump_-d/* | sort -t / -k2,2
	  807994 total
	     802 build1/objdump_-d/zavl.ko.log
	     802 build2/objdump_-d/zavl.ko.log
	    3695 build1/objdump_-d/zunicode.ko.log
	    3695 build2/objdump_-d/zunicode.ko.log
	    6333 build1/objdump_-d/zcommon.ko.log
	    6333 build2/objdump_-d/zcommon.ko.log
	    7365 build1/objdump_-d/znvpair.ko.log
	    7365 build2/objdump_-d/znvpair.ko.log
	   12189 build1/objdump_-d/spl.ko.log
	   12189 build2/objdump_-d/spl.ko.log
	   28087 build1/objdump_-d/zlua.ko.log
	   28087 build2/objdump_-d/zlua.ko.log
	   42498 build1/objdump_-d/icp.ko.log
	   42498 build2/objdump_-d/icp.ko.log
	  303028 build1/objdump_-d/zfs.ko.log
	  303028 build2/objdump_-d/zfs.ko.log

Revision history for this message

Mauricio Faria de Oliveira (mfo) wrote on 2019-08-28:

#3

Download full text (3.2 KiB)

Test Build 3) New behavior if ZFS modules are built with debug symbols

goal: show zfs debug symbols are correctly built and packaged into non-debug & debug packages.

- test packaging
- zfs built with debug symbols
- zfs modules present in debug package
- extra modules *have* .gnu_debuglink section

Test packaging, debug symbols *enabled* in zfs-dkms:

Modules are built with debug symbols, copied to debug package directory,
and stripped before being copied into strip/non-debug package directory.

II: dkms-build installing zfs into /home/ubuntu/dbgsym/unstable/debian/linux-image-unsigned-5.3.0-8-generic-dbgsym/usr/lib/debug/lib/modules/5.3.0-8-generic/kernel/zfs (debug symbols)
copying zavl.ko
stripping zavl.ko
copying znvpair.ko
stripping znvpair.ko
copying zunicode.ko
stripping zunicode.ko
copying zcommon.ko
stripping zcommon.ko
copying zfs.ko
stripping zfs.ko
copying icp.ko
stripping icp.ko
copying zlua.ko
stripping zlua.ko
copying spl.ko
stripping spl.ko
II: dkms-build installing zfs into /home/ubuntu/dbgsym/unstable/debian/linux-modules-5.3.0-8-generic/lib/modules/5.3.0-8-generic/kernel/zfs
signing zavl.ko
signing znvpair.ko
signing zunicode.ko
signing zcommon.ko
signing zfs.ko
signing icp.ko
signing zlua.ko
signing spl.ko
II: dkms-build build zfs complete

The ZFS modules are now present in the debug package:

$ dpkg-deb -x linux-image-unsigned-5.3.0-8-generic-dbgsym_5.3.0-8.9_amd64.ddeb ddeb-test-enabled

$ ls -1 ddeb-test-enabled/usr/lib/debug/lib/modules/5.3.0-8-generic/kernel/zfs/
icp.ko
spl.ko
zavl.ko
zcommon.ko
zfs.ko
zlua.ko
znvpair.ko
zunicode.ko

And now all modules in 'linux-modules' have the '.gnu_debuglink' section:

$ dpkg-deb -x linux-modules-5.3.0-8-generic_5.3.0-8.9_amd64.deb deb-modules
$ find deb-modules/ -name '*.ko' | while read ko; do objdump -h -j .gnu_debuglink $ko >/dev/null 2>&1 || echo "Module without debug link '$ko'"; done
$

The build log no longer shows ZFS modules as missing debug symbols:

$ grep WARNING build.log
echo "WARNING: Missing debug symbols for module '$module'."; \
WARNING: Missing debug symbols for module '/lib/modules/5.3.0-8-generic/kernel/virtualbox-guest/vboxguest.ko'.
WARNING: Missing debug symbols for module '/lib/modules/5.3.0-8-generic/kernel/virtualbox-guest/vboxsf.ko'.
$

The only modules in 'linux-modules-extra' without that continue to be virtualbox modules:

$ dpkg-deb -x linux-modules-extra-5.3.0-8-generic_5.3.0-8.9_amd64.deb deb-modules-extra
$ find deb-modules-extra/ -name '*.ko' | while read ko; do objdump -h -j .gnu_debuglink $ko >/dev/null 2>&1 || echo "Module without debug link '$ko'"; done
Module without debug link 'deb-modules-extra/lib/modules/5.3.0-8-generic/kernel/virtualbox-guest/vboxguest.ko'
Module without debug link 'deb-modules-extra/lib/modules/5.3.0-8-generic/kernel/virtualbox-guest/vboxsf.ko'
$

As reflected in the kernel build log.

$ grep WARNING build.log
echo "WARNING: Missing debug symbols for module '$module'."; \
WARNING: Missing debug symbols for module '/lib/modules/5.3.0-8-generic/kernel/virtualbox-guest/vboxguest.ko'.
WARNING: Missing debug symbols for module '/lib/modules/5...

Test Build 3) New behavior if ZFS modules are built with debug symbols

goal: show zfs debug symbols are correctly built and packaged into non-debug & debug packages.

- test packaging
- zfs built with debug symbols
- zfs modules present in debug package
- extra modules *have* .gnu_debuglink section

Test packaging, debug symbols *enabled* in zfs-dkms:

Modules are built with debug symbols, copied to debug package directory, 
and stripped before being copied into strip/non-debug package directory.

II: dkms-build installing zfs into /home/ubuntu/dbgsym/unstable/debian/linux-image-unsigned-5.3.0-8-generic-dbgsym/usr/lib/debug/lib/modules/5.3.0-8-generic/kernel/zfs (debug symbols)
	copying zavl.ko
	stripping zavl.ko
	copying znvpair.ko
	stripping znvpair.ko
	copying zunicode.ko
	stripping zunicode.ko
	copying zcommon.ko
	stripping zcommon.ko
	copying zfs.ko
	stripping zfs.ko
	copying icp.ko
	stripping icp.ko
	copying zlua.ko
	stripping zlua.ko
	copying spl.ko
	stripping spl.ko
	II: dkms-build installing zfs into /home/ubuntu/dbgsym/unstable/debian/linux-modules-5.3.0-8-generic/lib/modules/5.3.0-8-generic/kernel/zfs
	signing zavl.ko
	signing znvpair.ko
	signing zunicode.ko
	signing zcommon.ko
	signing zfs.ko
	signing icp.ko
	signing zlua.ko
	signing spl.ko
	II: dkms-build build zfs complete

The ZFS modules are now present in the debug package:

$ dpkg-deb -x linux-image-unsigned-5.3.0-8-generic-dbgsym_5.3.0-8.9_amd64.ddeb ddeb-test-enabled

$ ls -1 ddeb-test-enabled/usr/lib/debug/lib/modules/5.3.0-8-generic/kernel/zfs/
	icp.ko
	spl.ko
	zavl.ko
	zcommon.ko
	zfs.ko
	zlua.ko
	znvpair.ko
	zunicode.ko

And now all modules in 'linux-modules' have the '.gnu_debuglink' section:

$ dpkg-deb -x linux-modules-5.3.0-8-generic_5.3.0-8.9_amd64.deb deb-modules
	$ find deb-modules/ -name '*.ko' | while read ko; do objdump -h -j .gnu_debuglink $ko >/dev/null 2>&1 || echo "Module without debug link '$ko'"; done
	$

The build log no longer shows ZFS modules as missing debug symbols:

$ grep WARNING build.log 
		        echo "WARNING: Missing debug symbols for module '$module'."; \
	WARNING: Missing debug symbols for module '/lib/modules/5.3.0-8-generic/kernel/virtualbox-guest/vboxguest.ko'.
	WARNING: Missing debug symbols for module '/lib/modules/5.3.0-8-generic/kernel/virtualbox-guest/vboxsf.ko'.
	$

The only modules in 'linux-modules-extra' without that continue to be virtualbox modules:

$ dpkg-deb -x linux-modules-extra-5.3.0-8-generic_5.3.0-8.9_amd64.deb deb-modules-extra
	$ find deb-modules-extra/ -name '*.ko' | while read ko; do objdump -h -j .gnu_debuglink $ko >/dev/null 2>&1 || echo "Module without debug link '$ko'"; done
	Module without debug link 'deb-modules-extra/lib/modules/5.3.0-8-generic/kernel/virtualbox-guest/vboxguest.ko'
	Module without debug link 'deb-modules-extra/lib/modules/5.3.0-8-generic/kernel/virtualbox-guest/vboxsf.ko'
	$

As reflected in the kernel build log.

$ grep WARNING build.log 
		        echo "WARNING: Missing debug symbols for module '$module'."; \
	WARNING: Missing debug symbols for module '/lib/modules/5.3.0-8-generic/kernel/virtualbox-guest/vboxguest.ko'.
	WARNING: Missing debug symbols for module '/lib/modules/5.3.0-8-generic/kernel/virtualbox-guest/vboxsf.ko'.

Revision history for this message

Mauricio Faria de Oliveira (mfo) wrote on 2019-08-28:

#4

Test Build 4) All debug symbols disabled

goal: show no zfs debug symbol activity happens either (along w/ other debug symbol stuff)

- test packaging
- nothing built with debug symbols
- no debug package present
- no .gnu_debuglink section at all
- (no regressions)

Test packaging, debug symbols disabled at all (skipdbg=true).

The dkms-build script doesn't do any debug symbol work at all.

II: dkms-build installing zfs into /home/ubuntu/dbgsym/unstable/debian/linux-modules-5.3.0-8-generic/lib/modules/5.3.0-8-generic/kernel/zfs
signing zavl.ko
signing znvpair.ko
signing zunicode.ko
signing zcommon.ko
signing zfs.ko
signing icp.ko
signing zlua.ko
signing spl.ko
II: dkms-build build zfs complete

No debug sections are present in ZFS modules (as expected):

$ objdump -h deb-modules/lib/modules/5.3.0-8-generic/kernel/zfs/zfs.ko | grep debug
$

And the check for modules without debug symbols is not exercised (as expected):

$ grep WARNING build.log
$

$ find deb-modules/ -name '*.ko' | wc -l
1000

$ find deb-modules/ -name '*.ko' | while read ko; do objdump -h -j .gnu_debuglink $ko >/dev/null 2>&1 || echo "Module without debug link '$ko'"; done | wc -l
1000

$ find deb-modules-extra/ -name '*.ko' | wc -l
4508

$ find deb-modules-extra/ -name '*.ko' | while read ko; do objdump -h -j .gnu_debuglink $ko >/dev/null 2>&1 || echo "Module without debug link '$ko'"; done | wc -l
4508

Mauricio Faria de Oliveira (mfo) on 2019-08-28

description:

updated

Revision history for this message

Mauricio Faria de Oliveira (mfo) wrote on 2019-08-28:

#5

[Unstable][PATCH 0/6] Add support for ZFS debug symbols
https://lists.ubuntu.com/archives/kernel-team/2019-August/103425.html

Revision history for this message

Mauricio Faria de Oliveira (mfo) wrote on 2019-08-29:

#6

lp1840704_debdiffs.tar Edit (80.0 KiB, application/x-tar)

Attaching the debdiffs for zfs-linux/spl-linux on X/B/D/E,
for documentation purposes; will send testing/notes later.

Independently of the kernel packaging approach determined
to enable debug symbols on ZFS/SPL modules, these kind of
patches for the userspace packages are be required anyway,
and correctly performed that task when building with DKMS.

So I'll probably move forward with their SRU request soon,
in the benefit of having this available sooner if required
(i.e. so users/engineers in need of debug symbols may just
rebuild with DKMS using this, and be able to investigate.)

Nivedita Singhvi (niveditasinghvi) on 2019-08-29

tags:	added: sts
tags:	added: linux
Changed in linux (Ubuntu):
importance:	Undecided → High

Revision history for this message

Launchpad Janitor (janitor) wrote on 2019-10-10:

#7

Download full text (7.6 KiB)

This bug was fixed in the package linux - 5.3.0-17.18

---------------
linux (5.3.0-17.18) eoan; urgency=medium

* eoan/linux: 5.3.0-17.18 -proposed tracker (LP: #1846641)

* CVE-2019-17056
- nfc: enforce CAP_NET_RAW for raw sockets

* CVE-2019-17055
- mISDN: enforce CAP_NET_RAW for raw sockets

* CVE-2019-17054
- appletalk: enforce CAP_NET_RAW for raw sockets

* CVE-2019-17053
- ieee802154: enforce CAP_NET_RAW for raw sockets

* CVE-2019-17052
- ax25: enforce CAP_NET_RAW for raw sockets

* CVE-2019-15098
- ath6kl: fix a NULL-ptr-deref bug in ath6kl_usb_alloc_urb_from_pipe()

  * xHCI on AMD Stoney Ridge cannot detect USB 2.0 or 1.1 devices.
    (LP: #1846470)
    - x86/PCI: Avoid AMD FCH XHCI USB PME# from D0 defect

  * Re-enable linux-libc-dev build on i386 (LP: #1846508)
    - [Packaging] Build only linux-libc-dev for i386
    - [Debian] final-checks -- ignore archtictures with no binaries

  * arm64: loop on boot after installing linux-generic-hwe-18.04-edge/bionic-
    proposed (LP: #1845820)
    - [Config] Disable CONFIG_ARM_SMMU_DISABLE_BYPASS_BY_DEFAULT

* Revert ESE DASD discard support (LP: #1846219)
- SAUCE: Revert "s390/dasd: Add discard support for ESE volumes"

* Miscellaneous Ubuntu changes
- update dkms package versions

linux (5.3.0-16.17) eoan; urgency=medium

* eoan/linux: 5.3.0-16.17 -proposed tracker (LP: #1846204)

* zfs fails to build on s390x with debug symbols enabled (LP: #1846143)
- SAUCE: s390: Mark atomic const ops always inline

linux (5.3.0-15.16) eoan; urgency=medium

* eoan/linux: 5.3.0-15.16 -proposed tracker (LP: #1845987)

  * Drop i386 build for 19.10 (LP: #1845714)
    - [Packaging] Remove x32 arch references from control files
    - [Debian] final-checks -- Get arch list from debian/control

* ZFS kernel modules lack debug symbols (LP: #1840704)
- [Debian] Fix conditional for setting zfs debug package path

  * Use pyhon3-sphinx instead of python-sphinx for building html docs
    (LP: #1845808)
    - [Packaging] Update sphinx build dependencies to python3 packages

  * Kernel panic with 19.10 beta image (LP: #1845454)
    - efi/tpm: Don't access event->count when it isn't mapped.
    - efi/tpm: don't traverse an event log with no events
    - efi/tpm: only set efi_tpm_final_log_size after successful event log parsing

linux (5.3.0-14.15) eoan; urgency=medium

* eoan/linux: 5.3.0-14.15 -proposed tracker (LP: #1845728)

  * Drop i386 build for 19.10 (LP: #1845714)
    - [Debian] Remove support for producing i386 kernels
    - [Debian] Don't use CROSS_COMPILE for i386 configs

  * udevadm trigger will fail when trying to add /sys/devices/vio/
    (LP: #1845572)
    - SAUCE: powerpc/vio: drop bus_type from parent device

  * Trying to online dasd drive results in invalid input/output from the kernel
    on z/VM (LP: #1845323)
    - SAUCE: s390/dasd: Fix error handling during online processing

* intel-lpss driver conflicts with write-combining MTRR region (LP: #1845584)
- SAUCE: mfd: intel-lpss: add quirk for Dell XPS 13 7390 2-in-1

* Support Hi1620 zip hw accelerator (LP: #1845355)
- [Config] Enable HiSilicon QM/ZIP as module...

This bug was fixed in the package linux - 5.3.0-17.18

---------------
linux (5.3.0-17.18) eoan; urgency=medium

* eoan/linux: 5.3.0-17.18 -proposed tracker (LP: #1846641)

* CVE-2019-17056
    - nfc: enforce CAP_NET_RAW for raw sockets

* CVE-2019-17055
    - mISDN: enforce CAP_NET_RAW for raw sockets

* CVE-2019-17054
    - appletalk: enforce CAP_NET_RAW for raw sockets

* CVE-2019-17053
    - ieee802154: enforce CAP_NET_RAW for raw sockets

* CVE-2019-17052
    - ax25: enforce CAP_NET_RAW for raw sockets

* CVE-2019-15098
    - ath6kl: fix a NULL-ptr-deref bug in ath6kl_usb_alloc_urb_from_pipe()

* xHCI on AMD Stoney Ridge cannot detect USB 2.0 or 1.1 devices.
    (LP: #1846470)
    - x86/PCI: Avoid AMD FCH XHCI USB PME# from D0 defect

* Re-enable linux-libc-dev build on i386 (LP: #1846508)
    - [Packaging] Build only linux-libc-dev for i386
    - [Debian] final-checks -- ignore archtictures with no binaries

* arm64: loop on boot after installing linux-generic-hwe-18.04-edge/bionic-
    proposed (LP: #1845820)
    - [Config] Disable CONFIG_ARM_SMMU_DISABLE_BYPASS_BY_DEFAULT

* Revert ESE DASD discard support (LP: #1846219)
    - SAUCE: Revert "s390/dasd: Add discard support for ESE volumes"

* Miscellaneous Ubuntu changes
    - update dkms package versions

linux (5.3.0-16.17) eoan; urgency=medium

* eoan/linux: 5.3.0-16.17 -proposed tracker (LP: #1846204)

* zfs fails to build on s390x  with debug symbols enabled (LP: #1846143)
    - SAUCE: s390: Mark atomic const ops always inline

linux (5.3.0-15.16) eoan; urgency=medium

* eoan/linux: 5.3.0-15.16 -proposed tracker (LP: #1845987)

* Drop i386 build for 19.10 (LP: #1845714)
    - [Packaging] Remove x32 arch references from control files
    - [Debian] final-checks -- Get arch list from debian/control

* ZFS kernel modules lack debug symbols (LP: #1840704)
    - [Debian] Fix conditional for setting zfs debug package path

* Use pyhon3-sphinx instead of python-sphinx for building html docs
    (LP: #1845808)
    - [Packaging] Update sphinx build dependencies to python3 packages

* Kernel panic with 19.10 beta image (LP: #1845454)
    - efi/tpm: Don't access event->count when it isn't mapped.
    - efi/tpm: don't traverse an event log with no events
    - efi/tpm: only set efi_tpm_final_log_size after successful event log parsing

linux (5.3.0-14.15) eoan; urgency=medium

* eoan/linux: 5.3.0-14.15 -proposed tracker (LP: #1845728)

* Drop i386 build for 19.10 (LP: #1845714)
    - [Debian] Remove support for producing i386 kernels
    - [Debian] Don't use CROSS_COMPILE for i386 configs

* udevadm trigger will fail when trying to add /sys/devices/vio/
    (LP: #1845572)
    - SAUCE: powerpc/vio: drop bus_type from parent device

* Trying to online dasd drive results in invalid input/output from the kernel
    on z/VM (LP: #1845323)
    - SAUCE: s390/dasd: Fix error handling during online processing

* intel-lpss driver conflicts with write-combining MTRR region (LP: #1845584)
    - SAUCE: mfd: intel-lpss: add quirk for Dell XPS 13 7390 2-in-1

* Support Hi1620 zip hw accelerator (LP: #1845355)
    - [Config] Enable HiSilicon QM/ZIP as modules
    - crypto: hisilicon - add queue management driver for HiSilicon QM module
    - crypto: hisilicon - add hardware SGL support
    - crypto: hisilicon - add HiSilicon ZIP accelerator support
    - crypto: hisilicon - add SRIOV support for ZIP
    - Documentation: Add debugfs doc for hisi_zip
    - crypto: hisilicon - add debugfs for ZIP and QM
    - MAINTAINERS: add maintainer for HiSilicon QM and ZIP controller driver
    - crypto: hisilicon - fix kbuild warnings
    - crypto: hisilicon - add dependency for CRYPTO_DEV_HISI_ZIP
    - crypto: hisilicon - init curr_sgl_dma to fix compile warning
    - crypto: hisilicon - add missing single_release
    - crypto: hisilicon - fix error handle in hisi_zip_create_req_q
    - crypto: hisilicon - Fix warning on printing %p with dma_addr_t
    - crypto: hisilicon - Fix return value check in hisi_zip_acompress()
    - crypto: hisilicon - avoid unused function warning

* SafeSetID LSM should be built but disabled by default (LP: #1845391)
    - LSM: SafeSetID: Stop releasing uninitialized ruleset
    - [Config] Build SafeSetID LSM but don't enable it by default

* CONFIG_LSM should not specify loadpin since it is not built (LP: #1845383)
    - [Config] loadpin shouldn't be in CONFIG_LSM

* Add new pci-id's for CML-S, ICL (LP: #1845317)
    - drm/i915/icl: Add missing device ID
    - drm/i915/cml: Add Missing PCI IDs

* Thunderbolt support for ICL (LP: #1844680)
    - thunderbolt: Correct path indices for PCIe tunnel
    - thunderbolt: Move NVM upgrade support flag to struct icm
    - thunderbolt: Use 32-bit writes when writing ring producer/consumer
    - thunderbolt: Do not fail adding switch if some port is not implemented
    - thunderbolt: Hide switch attributes that are not set
    - thunderbolt: Expose active parts of NVM even if upgrade is not supported
    - thunderbolt: Add support for Intel Ice Lake
    - ACPI / property: Add two new Thunderbolt property GUIDs to the list

* Ubuntu 19.10 -  Additional PCI patch and fix (LP: #1844668)
    - s390/pci: fix MSI message data

* Enhanced Hardware Support - Finalize Naming (LP: #1842774)
    - s390: add support for IBM z15 machines
    - [Config] CONFIG_MARCH_Z15=n, CONFIG_TUNE_Z15=n

* Eoan update: v5.3.1 upstream stable release (LP: #1845642)
    - USB: usbcore: Fix slab-out-of-bounds bug during device reset
    - media: tm6000: double free if usb disconnect while streaming
    - phy: renesas: rcar-gen3-usb2: Disable clearing VBUS in over-current
    - ip6_gre: fix a dst leak in ip6erspan_tunnel_xmit
    - net/sched: fix race between deactivation and dequeue for NOLOCK qdisc
    - net_sched: let qdisc_put() accept NULL pointer
    - udp: correct reuseport selection with connected sockets
    - xen-netfront: do not assume sk_buff_head list is empty in error handling
    - net: dsa: Fix load order between DSA drivers and taggers
    - net: stmmac: Hold rtnl lock in suspend/resume callbacks
    - KVM: coalesced_mmio: add bounds checking
    - Documentation: sphinx: Add missing comma to list of strings
    - firmware: google: check if size is valid when decoding VPD data
    - serial: sprd: correct the wrong sequence of arguments
    - tty/serial: atmel: reschedule TX after RX was started
    - nl80211: Fix possible Spectre-v1 for CQM RSSI thresholds
    - Revert "arm64: Remove unnecessary ISBs from set_{pte,pmd,pud}"
    - ovl: fix regression caused by overlapping layers detection
    - phy: qcom-qmp: Correct ready status, again
    - floppy: fix usercopy direction
    - media: technisat-usb2: break out of loop at end of buffer
    - Linux 5.3.1

* ZFS kernel modules lack debug symbols (LP: #1840704)
    - [Debian]: Remove hardcoded $(pkgdir) in debug symbols handling
    - [Debian]: Handle debug symbols for modules in extras too
    - [Debian]: Check/link modules with debug symbols after DKMS modules
    - [Debian]: Warn about modules without debug symbols
    - [Debian]: dkms-build: new parameter for debug package directory
    - [Debian]: dkms-build: zfs: support for debug symbols
    - [Debian]: dkms-build: Avoid executing post-processor scripts twice
    - [Debian]: dkms-build: Move zfs special-casing into configure script

* /proc/self/maps paths missing on live session (was vlc won't start; eoan
    19.10 & bionic 18.04 ubuntu/lubuntu/kubuntu/xubuntu/ubuntu-mate dailies)
    (LP: #1842382)
    - SAUCE: Revert "UBUNTU: SAUCE: shiftfs: enable overlayfs on shiftfs"

-- Seth Forshee <seth.forshee@canonical.com>  Thu, 03 Oct 2019 16:57:05 -0500

Changed in linux (Ubuntu):
status:	In Progress → Fix Released

Revision history for this message

Ubuntu SRU Bot (ubuntu-sru-bot) wrote on 2019-11-12: Autopkgtest regression report (linux-gcp-5.3/5.3.0-1008.9~18.04.1)

#8

All autopkgtests for the newly accepted linux-gcp-5.3 (5.3.0-1008.9~18.04.1) for bionic have finished running.
The following regressions have been reported in tests triggered by the package:

linux-gcp-5.3/unknown (amd64)

Please visit the excuses page listed below and investigate the failures, proceeding afterwards as per the StableReleaseUpdates policy regarding autopkgtest regressions [1].

https://people.canonical.com/~ubuntu-archive/proposed-migration/bionic/update_excuses.html#linux-gcp-5.3

[1] https://wiki.ubuntu.com/StableReleaseUpdates#Autopkgtest_Regressions

Thank you!

Ubuntu
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ZFS kernel modules lack debug symbols

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ZFS kernel modules lack debug symbols

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