[Ubuntu 20.04] net/mlx5e: Fix endianness handling in pedit mask

It's upstream accepted since 5.6:
$ git tag --contains 404402abd5f9 | grep ^v
v5.6
v5.7-rc1

There is unfortnately no simple and clean cherry-pick possible of this commit to the ubuntu focal master-next tree. git cherry-pick complains with:

Performing inexact rename detection: 100% (3285744/3285744), done.
Auto-merging drivers/net/ethernet/mellanox/mlx5/core/en_tc.c
CONFLICT (content): Merge conflict in drivers/net/ethernet/mellanox/mlx5/core/en_tc.c
error: could not apply 404402abd5f9... net/mlx5e: Fix endianness handling in pedit mask
hint: after resolving the conflicts, mark the corrected paths
hint: with 'git add <paths>' or 'git rm <paths>'
hint: and commit the result with 'git commit'

The status is:

On branch master-next
Your branch is ahead of 'origin/master-next' by 2 commits.
  (use "git push" to publish your local commits)

You are currently cherry-picking commit 404402abd5f9.
  (fix conflicts and run "git cherry-pick --continue")
  (use "git cherry-pick --skip" to skip this patch)
  (use "git cherry-pick --abort" to cancel the cherry-pick operation)

Unmerged paths:
  (use "git add <file>..." to mark resolution)
 both modified: drivers/net/ethernet/mellanox/mlx5/core/en_tc.c

no changes added to commit (use "git add" and/or "git commit -a")

and diff:

diff --cc drivers/net/ethernet/mellanox/mlx5/core/en_tc.c
index 1f9107d83848,ec5fc52bf572..000000000000
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_tc.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_tc.c
@@@ -2421,13 -2475,12 +2421,22 @@@ static int offload_pedit_fields(struct
                if (skip)
                        continue;

++<<<<<<< HEAD
 + field_bsize = f->size * BITS_PER_BYTE;
 +
 + if (field_bsize == 32) {
 + mask_be32 = *(__be32 *)&mask;
 + mask = (__force unsigned long)cpu_to_le32(be32_to_cpu(mask_be32));
 + } else if (field_bsize == 16) {
 + mask_be16 = *(__be16 *)&mask;
++=======
+ if (f->field_bsize == 32) {
+ mask_be32 = (__be32)mask;
+ mask = (__force unsigned long)cpu_to_le32(be32_to_cpu(mask_be32));
+ } else if (f->field_bsize == 16) {
+ mask_be32 = (__be32)mask;
+ mask_be16 = *(__be16 *)&mask_be32;
++>>>>>>> 404402abd5f9... net/mlx5e: Fix endianness handling in pedit mask
                        mask = (__force unsigned long)cpu_to_le16(be16_to_cpu(mask_be16));
                }

Since this touches common code, please double check what else is needed to get it cleanly in.
git mergetool shows a lot of differences between focal master-next and 5.6/5.7 upstream in drivers/net/ethernet/mellanox/mlx5/core/en_tc.c
So it needs to handled very carefully ...

------- Comment From <email address hidden> 2020-04-23 08:56 EDT-------
Sebastian has supplied me with the following information for reproducing the issue and is currently working on a backport:

echo 1 > /sys/class/net/p0/device/sriov_numvfs
echo 0101:00:00.0 > /sys/bus/pci/drivers/mlx5_core/unbind
devlink dev eswitch set pci/0100:00:00.0 mode switchdev
ethtool -K p0 hw-tc-offload on
echo 0101:00:00.0 > /sys/bus/pci/drivers/mlx5_core/bind
tc qdisc add dev p0 ingress
tc qdisc add dev p0v0_r ingress
tc filter add dev p0v0_r protocol ip parent ffff:0 prio 1 flower skip_sw action pedit ex munge eth dst set 11:22:33:44:55:66 action goto chain 1

Without the patch the last command would fail with the following output in dmesg

[ 548.966006] mlx5_core 0100:00:00.0: mlx5_cmd_check:711:(pid 5220): SET_FLOW_TABLE_ENTRY(0x936) op_mod(0x0) failed, status bad parameter(0x3), syndrome (0x144b7a)

This was only tested on Z but we suspect that the same problem should also occur on other Big Endian architectures

------- Comment on attachment From <email address hidden> 2020-04-24 11:41 EDT-------

This is the upstream commit

404402abd5f90aa90a134eb9604b1750c1941529 ("net/mlx5: fix endianness handling in pedit mask")

backported for focal-master next. It has been running internally for a while so has seen testing on Z, as mentioned before we believe this should also be necessary for other Big Endian architectures.

Fix:
404402abd5f9 "net/mlx5e: Fix endianness handling in pedit mask"
upstream with v5.6

Kernel SRU request submitted:
https://lists.ubuntu.com/archives/kernel-team/2020-May/thread.html#109623
Changing status to 'In Progress'.

This bug is awaiting verification that the kernel in -proposed solves the problem. Please test the kernel and update this bug with the results. If the problem is solved, change the tag 'verification-needed-focal' to 'verification-done-focal'. If the problem still exists, change the tag 'verification-needed-focal' to 'verification-failed-focal'.

If verification is not done by 5 working days from today, this fix will be dropped from the source code, and this bug will be closed.

See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Thank you!

------- Comment From <email address hidden> 2020-05-20 03:28 EDT-------
Fix already verified by IBM. Works as expected.

This bug was fixed in the package linux - 5.4.0-37.41

---------------
linux (5.4.0-37.41) focal; urgency=medium

  * CVE-2020-0543
    - SAUCE: x86/speculation/spectre_v2: Exclude Zhaoxin CPUs from SPECTRE_V2
    - SAUCE: x86/cpu: Add a steppings field to struct x86_cpu_id
    - SAUCE: x86/cpu: Add 'table' argument to cpu_matches()
    - SAUCE: x86/speculation: Add Special Register Buffer Data Sampling (SRBDS)
      mitigation
    - SAUCE: x86/speculation: Add SRBDS vulnerability and mitigation documentation
    - SAUCE: x86/speculation: Add Ivy Bridge to affected list

 -- Marcelo Henrique Cerri <email address hidden> Wed, 03 Jun 2020 11:24:23 -0300

All autopkgtests for the newly accepted linux-oracle-5.4 (5.4.0-1019.19~18.04.1) for bionic have finished running.
The following regressions have been reported in tests triggered by the package:

zfs-linux/unknown (armhf)

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-oracle-5.4

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

Thank you!

This bug was fixed in the package linux - 5.4.0-42.46

---------------
linux (5.4.0-42.46) focal; urgency=medium

  * focal/linux: 5.4.0-42.46 -proposed tracker (LP: #1887069)

  * linux 4.15.0-109-generic network DoS regression vs -108 (LP: #1886668)
    - SAUCE: Revert "netprio_cgroup: Fix unlimited memory leak of v2 cgroups"

linux (5.4.0-41.45) focal; urgency=medium

  * focal/linux: 5.4.0-41.45 -proposed tracker (LP: #1885855)

  * Packaging resync (LP: #1786013)
    - update dkms package versions

  * CVE-2019-19642
    - kernel/relay.c: handle alloc_percpu returning NULL in relay_open

  * CVE-2019-16089
    - SAUCE: nbd_genl_status: null check for nla_nest_start

  * CVE-2020-11935
    - aufs: do not call i_readcount_inc()

  * ip_defrag.sh in net from ubuntu_kernel_selftests failed with 5.0 / 5.3 / 5.4
    kernel (LP: #1826848)
    - selftests: net: ip_defrag: ignore EPERM

  * Update lockdown patches (LP: #1884159)
    - SAUCE: acpi: disallow loading configfs acpi tables when locked down

  * seccomp_bpf fails on powerpc (LP: #1885757)
    - SAUCE: selftests/seccomp: fix ptrace tests on powerpc

  * Introduce the new NVIDIA 418-server and 440-server series, and update the
    current NVIDIA drivers (LP: #1881137)
    - [packaging] add signed modules for the 418-server and the 440-server
      flavours

 -- Khalid Elmously <email address hidden> Thu, 09 Jul 2020 19:50:26 -0400