CONFIG_DEBUG_FS is not enabled by "make zfcpdump_defconfig" with Ubuntu 17.10 (kernel 4.13)

Bug #1719290 reported by bugproxy
8
This bug affects 1 person
Affects Status Importance Assigned to Milestone
Ubuntu on IBM z Systems
Fix Released
High
Canonical Kernel Team
linux (Ubuntu)
Fix Released
High
Skipper Bug Screeners

Bug Description

Ubuntu 17.10 uses kernel 4.13.

We just found out that on this kernel version CONFIG_DEBUG_FS is not enabled by "make zfcpdump_defconfig".

This makes zfcpdump fail with the following error message:

ERROR: Unable to mount debugfs
No such file or directory

Patch solving this problem is attached

As reference following bugzilla
As reference h
IBM bugzilla for enabling zfcpdump: https://bugzilla.linux.ibm.com/show_bug.cgi?id=139974

or Launchpad
https://bugs.launchpad.net/ubuntu/+source/s390-tools/+bug/1565841

== Comment: #1 - Heinz-Werner Seeck <email address hidden> - 2017-09-25 06:00:23 ==

CVE References

Revision history for this message
bugproxy (bugproxy) wrote : zfcpdump config patch

Default Comment by Bridge

tags: added: architecture-s39064 bugnameltc-159188 severity-high targetmilestone-inin1710
Changed in ubuntu:
assignee: nobody → Skipper Bug Screeners (skipper-screen-team)
affects: ubuntu → linux (Ubuntu)
Frank Heimes (fheimes)
Changed in ubuntu-z-systems:
importance: Undecided → High
assignee: nobody → Canonical Kernel Team (canonical-kernel-team)
Changed in linux (Ubuntu):
importance: Undecided → High
status: New → Triaged
Revision history for this message
Joseph Salisbury (jsalisbury) wrote :

CONFIG_DEBUG_FS should be enabled as of Ubuntu-4.13.0-10.11~171. Can you test that version or newer and see if this bug is resolved?

tags: added: kernel-da-key
Revision history for this message
Frank Heimes (fheimes) wrote :

I just did a brief check on an Artful install based on the daily image from the 22nd and it looks like it's indeed already enabled:

ubuntu@s1lp11:/$ lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu Artful Aardvark (development branch)
Release: 17.10
Codename: artful
ubuntu@s1lp11:/$ uname -r
4.13.0-11-generic
ubuntu@s1lp11:/$ grep CONFIG_DEBUG_FS /boot/config-4.13.0-11-generic
CONFIG_DEBUG_FS=y

Changed in ubuntu-z-systems:
status: New → Triaged
Revision history for this message
bugproxy (bugproxy) wrote : Comment bridged from LTC Bugzilla

------- Comment From <email address hidden> 2017-09-26 07:23 EDT-------
(In reply to comment #7)
> I just did a brief check on an Artful install based on the daily image from
> the 22nd and it looks like it's indeed already enabled:
>
> ubuntu@s1lp11:/$ lsb_release -a
> No LSB modules are available.
> Distributor ID: Ubuntu
> Description: Ubuntu Artful Aardvark (development branch)
> Release: 17.10
> Codename: artful
> ubuntu@s1lp11:/$ uname -r
> 4.13.0-11-generic
> ubuntu@s1lp11:/$ grep CONFIG_DEBUG_FS /boot/config-4.13.0-11-generic
> CONFIG_DEBUG_FS=y

For zfcpdump we have a special kernel package "zfcpdump-kernel".
Have you also checked the config for that kernel?

Revision history for this message
Dimitri John Ledkov (xnox) wrote :

zfcpdump kernel is escalated to the kernel team.

Changed in zfcpdump-kernel (Ubuntu Artful):
status: New → Triaged
importance: Undecided → High
assignee: nobody → Canonical Kernel Team (canonical-kernel-team)
Revision history for this message
Dimitri John Ledkov (xnox) wrote :

@hws @michael.holzheu @schwidefsky

It seems like schwidefsky updated s390 config upstream in v4.12 to remove -CONFIG_DEBUG_FS=y for the zfcpdump_defconfig. Meaning any Linux on Z systems using v4.12+ default zfcpdump_defconfig from upstream linux source tree will get a bad configuration. It seems counter productive to ask all downstreams to patch for this config issue.

Are you going to get in touch with schwidefsky to re-introduce CONFIG_DEBUG_FS=y in the zfcpdump_defconfig and get it applied in the stable trees too?

Also, i believe zfcpdump-kernel that we currently ship does have debugfs enabled. Are you using zfcpdump-kernel as provided in ubuntu? But we will note and will explicitely enable CONFIG_DEBUG_FS=y when we refress zfcpdump-kernel with v4.13+.

Regards,

Dimitri.

Changed in zfcpdump-kernel (Ubuntu Artful):
status: Triaged → Incomplete
Changed in linux (Ubuntu Artful):
status: Triaged → Incomplete
Changed in ubuntu-z-systems:
status: Triaged → Incomplete
no longer affects: zfcpdump-kernel (Ubuntu Artful)
no longer affects: linux (Ubuntu Artful)
Changed in linux-hwe (Ubuntu):
status: New → Incomplete
Seth Forshee (sforshee)
Changed in linux (Ubuntu):
status: Incomplete → Fix Committed
Revision history for this message
bugproxy (bugproxy) wrote :

------- Comment From <email address hidden> 2017-10-05 12:52 EDT-------
(In reply to comment #11)
> @hws @michael.holzheu @schwidefsky
>
> It seems like schwidefsky updated s390 config upstream in v4.12 to remove
> -CONFIG_DEBUG_FS=y for the zfcpdump_defconfig. Meaning any Linux on Z
> systems using v4.12+ default zfcpdump_defconfig from upstream linux source
> tree will get a bad configuration. It seems counter productive to ask all
> downstreams to patch for this config issue.
>
> Are you going to get in touch with schwidefsky to re-introduce
> CONFIG_DEBUG_FS=y in the zfcpdump_defconfig and get it applied in the stable
> trees too?

I already discussed this with Martin Schwidefsky and we decided *not* to go via stable but instead "warn" Ubuntu explicitly.

AFAIK you are the only official distribution that uses 4.13 for zfcpdump - therefore IMHO this should be sufficient.

> Also, i believe zfcpdump-kernel that we currently ship does have debugfs
> enabled. Are you using zfcpdump-kernel as provided in ubuntu?

I did not check anything - this bugzilla was just a heads-up.

> But we will
> note and will explicitely enable CONFIG_DEBUG_FS=y when we refress
> zfcpdump-kernel with v4.13+.

Thanks.

Revision history for this message
Launchpad Janitor (janitor) wrote :
Download full text (16.2 KiB)

This bug was fixed in the package linux - 4.13.0-15.16

---------------
linux (4.13.0-15.16) artful; urgency=low

  * linux: 4.13.0-15.16 -proposed tracker (LP: #1721373)

  * Boot regression on POWER9 (LP: #1721391)
    - Revert "crypto/nx: Add P9 NX support for 842 compression engine"
    - Revert "crypto/nx: Add P9 NX specific error codes for 842 engine"
    - Revert "crypto/nx: Use kzalloc for workmem allocation"
    - Revert "crypto/nx: Add nx842_add_coprocs_list function"
    - Revert "crypto/nx: Create nx842_delete_coprocs function"
    - Revert "crypto/nx: Create nx842_configure_crb function"
    - Revert "crypto/nx: Rename nx842_powernv_function as icswx function"
    - Revert "UBUNTU: [Config] CONFIG_PPC_VAS=y"
    - Revert "powerpc/powernv/vas: Define copy/paste interfaces"
    - Revert "powerpc/powernv/vas: Define vas_tx_win_open()"
    - Revert "powerpc/powernv/vas: Define vas_win_close() interface"
    - Revert "powerpc/powernv/vas: Define vas_rx_win_open() interface"
    - Revert "powerpc/powernv/vas: Define helpers to alloc/free windows"
    - Revert "powerpc/powernv/vas: Define helpers to init window context"
    - Revert "powerpc/powernv/vas: Define helpers to access MMIO regions"
    - Revert "powerpc/powernv/vas: Define vas_init() and vas_exit()"
    - Revert "powerpc/powernv: Move GET_FIELD/SET_FIELD to vas.h"
    - Revert "powerpc/powernv/vas: Define macros, register fields and structures"
    - Revert "powerpc/powernv: Enable PCI peer-to-peer"
    - Revert "powerpc/powernv: Add support to set power-shifting-ratio"
    - Revert "powerpc/powernv: Add support for powercap framework"
    - Revert "powerpc/perf: Add nest IMC PMU support"
    - Revert "powerpc/powernv: Detect and create IMC device"
    - Revert "powerpc/powernv: Add IMC OPAL APIs"

  * smartpqi patches for Artful (LP: #1721381)
    - scsi: smartpqi: add pqi reset quiesce support
    - scsi: smartpqi: enhance BMIC cache flush
    - scsi: smartpqi: update pqi passthru ioctl
    - scsi: smartpqi: cleanup doorbell register usage.
    - scsi: smartpqi: update kexec and power down support
    - scsi: smartpqi: add in new controller ids
    - scsi: smartpqi: change driver version to 1.1.2-125

  * CONFIG_DEBUG_FS is not enabled by "make zfcpdump_defconfig" with Ubuntu
    17.10 (kernel 4.13) (LP: #1719290)
    - SAUCE: s390: update zfcpdump_defconfig

  * [Feature] PXE boot with Intel Omni-Path (LP: #1712031)
    - d-i: Add hfi1 to nic-modules

  * [Feature]CNL:New device IDs for CNL (LP: #1685729)
    - pinctrl: intel: Add Intel Cannon Lake PCH-H pin controller support

linux (4.13.0-14.15) artful; urgency=low

  * linux: 4.13.0-14.15 -proposed tracker (LP: #1721122)

  * [Artful] ltp rwtest - Unable to handle kernel paging request at virtual
    address (LP: #1721067)
    - arm64: mm: Use READ_ONCE when dereferencing pointer to pte table

  * linux 4.13.0-13.14 ADT test failure with linux 4.13.0-13.14 (LP: #1720779)
    - SAUCE: LSM stacking: check for invalid zero sized writes

  * Add installer support for Broadcom BCM573xx network drivers. (LP: #1720466)
    - d-i: Add bnxt_en to nic-modules.

  * Miscellaneous Ubuntu changes
    - [Packaging] Include arch/arm6...

Changed in linux (Ubuntu):
status: Fix Committed → Fix Released
Revision history for this message
Dimitri John Ledkov (xnox) wrote :

> AFAIK you are the only official distribution that uses 4.13 for zfcpdump - therefore IMHO this should be sufficient.
That is not true. We do not use v4.13 kernel for zfcpdump-kernel package. zfcpdump-kernel package is based on v4.9 and upgrading that to v4.10+ fails to perform any dumps at all.

Please see https://bugs.launchpad.net/ubuntu/+source/zfcpdump-kernel/+bug/1722735 which has been requested for reverse-proxy.

Why was debugfs disabled upstream? Especially since s390-tools explicitly tries to mount debugfs.

Changed in ubuntu-z-systems:
status: Incomplete → Confirmed
no longer affects: linux-hwe (Ubuntu)
no longer affects: zfcpdump-kernel (Ubuntu)
Revision history for this message
Dimitri John Ledkov (xnox) wrote :

That other bug was reverse-proxied as LTC-159968 please see that for further discussion on upgrading Ubuntu's zfcpdump-kernel to 4.13.

Changed in ubuntu-z-systems:
status: Confirmed → Fix Released
Revision history for this message
bugproxy (bugproxy) wrote :

------- Comment From <email address hidden> 2017-10-11 06:58 EDT-------
IBM Bugzilla Status -> closed, Fix Released within Artful , follow-on problems will be handled by BZ159968 , LP1722735

Revision history for this message
bugproxy (bugproxy) wrote :

------- Comment From <email address hidden> 2017-10-11 09:01 EDT-------
(In reply to comment #14)
[snip]

>
> Why was debugfs disabled upstream? Especially since s390-tools explicitly
> tries to mount debugfs.

I asked the responsible person: It was just by accident.
Sorry for that.

Revision history for this message
bugproxy (bugproxy) wrote :

------- Comment From <email address hidden> 2017-10-11 10:32 EDT-------
(In reply to comment #14)
> > AFAIK you are the only official distribution that uses 4.13 for zfcpdump - therefore IMHO this should be sufficient.
> That is not true. We do not use v4.13 kernel for zfcpdump-kernel package.
> zfcpdump-kernel package is based on v4.9 and upgrading that to v4.10+ fails
> to perform any dumps at all.
>
> Please see
> https://bugs.launchpad.net/ubuntu/+source/zfcpdump-kernel/+bug/1722735 which
> has been requested for reverse-proxy.

We looked into the report: It looks like the initramfs with the zfcpdump user space is not detected for some reason.

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