selftests net: fix bpf build error

.github/actions/vmtest/action.yml

@@ -0,0 +1,39 @@
+name: 'vmtest'
+description: 'Build + run vmtest'
+inputs:
+  arch:
+    description: 'what arch to test'
+    required: true
+    default: 'x86_64'
+  toolchain:
+    description: 'what toolchain to use'
+    required: true
+    default: 'gcc'
+runs:
+  using: "composite"
+  steps:
+    # 1. Setup environment
+    - name: Setup build environment
+      uses: libbpf/ci/setup-build-env@master
+    # 2. Build
+    - name: Build kernel image
+      shell: bash
+      run: ${GITHUB_ACTION_PATH}/build.sh ${{ inputs.arch }} ${{ inputs.toolchain }}
+    - name: Build selftests
+      shell: bash
+      run: ${GITHUB_ACTION_PATH}/build_selftests.sh ${{ inputs.toolchain }}
+      env:
+        VMLINUX_BTF: ${{ github.workspace }}/vmlinux
+    # 3. Test
+    - name: Prepare rootfs
+      uses: libbpf/ci/prepare-rootfs@master
+      with:
+        project-name: 'libbpf'
+        arch: ${{ inputs.arch }}
+        kernel-root: '.'
+    - name: Run selftests
+      uses: libbpf/ci/run-qemu@master
+      with:
+        arch: ${{ inputs.arch}}
+        img: '/tmp/root.img'
+        vmlinuz: '${{ github.workspace }}/vmlinuz'

.github/actions/vmtest/build.sh

@@ -0,0 +1,24 @@
+#!/bin/bash
+
+set -euo pipefail
+
+ARCH="$1"
+TOOLCHAIN="$2"
+TOOLCHAIN_NAME="$(echo $TOOLCHAIN | cut -d '-' -f 1)"
+TOOLCHAIN_VERSION="$(echo $TOOLCHAIN | cut -d '-' -f 2)"
+
+if [ "$TOOLCHAIN_NAME" == "llvm" ]; then
+export LLVM="-$TOOLCHAIN_VERSION"
+fi
+
+THISDIR="$(cd $(dirname $0) && pwd)"
+
+source "${THISDIR}"/helpers.sh
+
+travis_fold start build_kernel "Building kernel with $TOOLCHAIN"
+
+cp ${GITHUB_WORKSPACE}/travis-ci/vmtest/configs/config-latest.${ARCH} .config
+
+make -j $((4*$(nproc))) olddefconfig all > /dev/null
+
+travis_fold end build_kernel

.github/actions/vmtest/build_selftests.sh

@@ -0,0 +1,52 @@
+#!/bin/bash
+
+set -euo pipefail
+
+THISDIR="$(cd $(dirname $0) && pwd)"
+
+source "${THISDIR}"/helpers.sh
+
+TOOLCHAIN="$1"
+TOOLCHAIN_NAME="$(echo $TOOLCHAIN | cut -d '-' -f 1)"
+TOOLCHAIN_VERSION="$(echo $TOOLCHAIN | cut -d '-' -f 2)"
+
+if [ "$TOOLCHAIN_NAME" == "llvm" ]; then
+export LLVM="-$TOOLCHAIN_VERSION"
+LLVM_VER=$TOOLCHAIN_VERSION
+else
+LLVM_VER=15
+fi
+
+travis_fold start prepare_selftests "Building selftests with $TOOLCHAIN"
+
+LIBBPF_PATH="${REPO_ROOT}"
+
+PREPARE_SELFTESTS_SCRIPT=${THISDIR}/prepare_selftests-${KERNEL}.sh
+if [ -f "${PREPARE_SELFTESTS_SCRIPT}" ]; then
+	(cd "${REPO_ROOT}/${REPO_PATH}/tools/testing/selftests/bpf" && ${PREPARE_SELFTESTS_SCRIPT})
+fi
+
+if [[ "${KERNEL}" = 'LATEST' ]]; then
+	VMLINUX_H=
+else
+	VMLINUX_H=${THISDIR}/vmlinux.h
+fi
+
+cd ${REPO_ROOT}/${REPO_PATH}
+make \
+	CLANG=clang-${LLVM_VER} \
+	LLC=llc-${LLVM_VER} \
+	LLVM_STRIP=llvm-strip-${LLVM_VER} \
+	VMLINUX_BTF="${VMLINUX_BTF}" \
+	VMLINUX_H="${VMLINUX_H}" \
+	-C "${REPO_ROOT}/${REPO_PATH}/tools/testing/selftests/bpf" \
+	-j $((4*$(nproc))) > /dev/null
+cd -
+mkdir "${LIBBPF_PATH}"/selftests
+cp -R "${REPO_ROOT}/${REPO_PATH}/tools/testing/selftests/bpf" \
+	"${LIBBPF_PATH}"/selftests
+cd "${LIBBPF_PATH}"
+rm selftests/bpf/.gitignore
+git add selftests
+
+travis_fold end prepare_selftests

.github/actions/vmtest/helpers.sh

@@ -0,0 +1,44 @@
+# $1 - start or end
+# $2 - fold identifier, no spaces
+# $3 - fold section description
+travis_fold() {
+  local YELLOW='\033[1;33m'
+  local NOCOLOR='\033[0m'
+  if [ -z ${GITHUB_WORKFLOW+x} ]; then
+    echo travis_fold:$1:$2
+    if [ ! -z "${3:-}" ]; then
+      echo -e "${YELLOW}$3${NOCOLOR}"
+    fi
+    echo
+  else
+    if [ $1 = "start" ]; then
+      line="::group::$2"
+      if [ ! -z "${3:-}" ]; then
+        line="$line - ${YELLOW}$3${NOCOLOR}"
+      fi
+    else
+      line="::endgroup::"
+    fi
+    echo -e "$line"
+  fi
+}
+
+__print() {
+  local TITLE=""
+  if [[ -n $2 ]]; then
+      TITLE=" title=$2"
+  fi
+  echo "::$1${TITLE}::$3"
+}
+
+# $1 - title
+# $2 - message
+print_error() {
+  __print error $1 $2
+}
+
+# $1 - title
+# $2 - message
+print_notice() {
+  __print notice $1 $2
+}

.github/workflows/test.yml

@@ -0,0 +1,57 @@
+name: bpf-ci
+
+on:
+  pull_request:
+
+concurrency: 
+  group: ci-test-${{ github.head_ref }}
+  cancel-in-progress: true
+
+jobs:
+  VM_Test:
+    runs-on: ${{ matrix.runs_on }}
+    name: Kernel ${{ matrix.kernel }} on ${{ matrix.runs_on }} with ${{ matrix.toolchain }}
+    timeout-minutes: 100
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - kernel: 'LATEST'
+            runs_on: ubuntu-latest
+            arch: 'x86_64'
+            toolchain: 'gcc'
+          - kernel: 'LATEST'
+            runs_on: ubuntu-latest
+            arch: 'x86_64'
+            toolchain: 'llvm-15'
+          - kernel: 'LATEST'
+            runs_on: z15
+            arch: 's390x'
+            toolchain: 'gcc'
+    env:
+      AUTHOR_EMAIL: "$(git log -1 --pretty=\"%aE\")"
+      KERNEL: LATEST
+      REPO_ROOT: ${{ github.workspace }}
+      REPO_PATH: ""
+    steps:
+      - uses: actions/checkout@v2
+      - if: ${{ github.repository != 'kernel-patches/bpf' && github.repository != 'kernel-patches/bpf-rc' }}
+        name: Download bpf-next tree
+        uses: libbpf/ci/get-linux-source@master
+        with:
+          dest: '.kernel'
+      - if: ${{ github.repository != 'kernel-patches/bpf' && github.repository != 'kernel-patches/bpf-rc' }}
+        name: Move linux source in place
+        shell: bash
+        run: |
+          rm -rf .kernel/.git
+          cp -rf .kernel/. .
+          rm -rf .kernel
+      - uses: libbpf/ci/patch-kernel@master
+        with:
+          patches-root: '${{ github.workspace }}/travis-ci/diffs'
+          repo-root: '${{ github.workspace }}'
+      - uses: ./.github/actions/vmtest
+        with:
+          arch: ${{ matrix.arch }}
+          toolchain: ${{ matrix.toolchain }}

README

@@ -1,18 +0,0 @@
-Linux kernel
-============
-
-There are several guides for kernel developers and users. These guides can
-be rendered in a number of formats, like HTML and PDF. Please read
-Documentation/admin-guide/README.rst first.
-
-In order to build the documentation, use ``make htmldocs`` or
-``make pdfdocs``.  The formatted documentation can also be read online at:
-
-    https://www.kernel.org/doc/html/latest/
-
-There are various text files in the Documentation/ subdirectory,
-several of them using the Restructured Text markup notation.
-
-Please read the Documentation/process/changes.rst file, as it contains the
-requirements for building and running the kernel, and information about
-the problems which may result by upgrading your kernel.

tools/testing/selftests/net/bpf/Makefile

@@ -2,6 +2,7 @@
 
 CLANG ?= clang
 CCINCLUDE += -I../../bpf
+CCINCLUDE += -I../../../../lib
 CCINCLUDE += -I../../../../../usr/include/
 
 TEST_CUSTOM_PROGS = $(OUTPUT)/bpf/nat6to4.o

travis-ci/diffs/0001-selftests-bpf-Limit-unroll_count-for-pyperf600-test.diff

@@ -0,0 +1,89 @@
+From 8c89b5db7a2894e33417dd69680729e8f65f5709 Mon Sep 17 00:00:00 2001
+From: Yonghong Song <yhs@fb.com>
+Date: Mon, 18 Apr 2022 21:32:30 -0700
+Subject: [PATCH] selftests/bpf: Limit unroll_count for pyperf600 test
+
+LLVM commit [1] changed loop pragma behavior such that
+full loop unroll is always honored with user pragma.
+Previously, unroll count also depends on the unrolled
+code size. For pyperf600, without [1], the loop unroll
+count is 150. With [1], the loop unroll count is 600.
+
+The unroll count of 600 caused the program size close to
+298k and this caused the following code is generated:
+         0:       7b 1a 00 ff 00 00 00 00 *(u64 *)(r10 - 256) = r1
+  ;       uint64_t pid_tgid = bpf_get_current_pid_tgid();
+         1:       85 00 00 00 0e 00 00 00 call 14
+         2:       bf 06 00 00 00 00 00 00 r6 = r0
+  ;       pid_t pid = (pid_t)(pid_tgid >> 32);
+         3:       bf 61 00 00 00 00 00 00 r1 = r6
+         4:       77 01 00 00 20 00 00 00 r1 >>= 32
+         5:       63 1a fc ff 00 00 00 00 *(u32 *)(r10 - 4) = r1
+         6:       bf a2 00 00 00 00 00 00 r2 = r10
+         7:       07 02 00 00 fc ff ff ff r2 += -4
+  ;       PidData* pidData = bpf_map_lookup_elem(&pidmap, &pid);
+         8:       18 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 r1 = 0 ll
+        10:       85 00 00 00 01 00 00 00 call 1
+        11:       bf 08 00 00 00 00 00 00 r8 = r0
+  ;       if (!pidData)
+        12:       15 08 15 e8 00 00 00 00 if r8 == 0 goto -6123 <LBB0_27588+0xffffffffffdae100>
+
+Note that insn 12 has a branch offset -6123 which is clearly illegal
+and will be rejected by the verifier. The negative offset is due to
+the branch range is greater than INT16_MAX.
+
+This patch changed the unroll count to be 150 to avoid above
+branch target insn out-of-range issue. Also the llvm is enhanced ([2])
+to assert if the branch target insn is out of INT16 range.
+
+  [1] https://reviews.llvm.org/D119148
+  [2] https://reviews.llvm.org/D123877
+
+Signed-off-by: Yonghong Song <yhs@fb.com>
+Signed-off-by: Alexei Starovoitov <ast@kernel.org>
+Link: https://lore.kernel.org/bpf/20220419043230.2928530-1-yhs@fb.com
+---
+ tools/testing/selftests/bpf/progs/pyperf.h    |  4 ++++
+ tools/testing/selftests/bpf/progs/pyperf600.c | 11 +++++++----
+ 2 files changed, 11 insertions(+), 4 deletions(-)
+
+diff --git a/tools/testing/selftests/bpf/progs/pyperf.h b/tools/testing/selftests/bpf/progs/pyperf.h
+index 1ed28882daf3..5d3dc4d66d47 100644
+--- a/tools/testing/selftests/bpf/progs/pyperf.h
++++ b/tools/testing/selftests/bpf/progs/pyperf.h
+@@ -299,7 +299,11 @@ int __on_event(struct bpf_raw_tracepoint_args *ctx)
+ #ifdef NO_UNROLL
+ #pragma clang loop unroll(disable)
+ #else
++#ifdef UNROLL_COUNT
++#pragma clang loop unroll_count(UNROLL_COUNT)
++#else
+ #pragma clang loop unroll(full)
++#endif
+ #endif /* NO_UNROLL */
+ 		/* Unwind python stack */
+ 		for (int i = 0; i < STACK_MAX_LEN; ++i) {
+diff --git a/tools/testing/selftests/bpf/progs/pyperf600.c b/tools/testing/selftests/bpf/progs/pyperf600.c
+index cb49b89e37cd..ce1aa5189cc4 100644
+--- a/tools/testing/selftests/bpf/progs/pyperf600.c
++++ b/tools/testing/selftests/bpf/progs/pyperf600.c
+@@ -1,9 +1,12 @@
+ // SPDX-License-Identifier: GPL-2.0
+ // Copyright (c) 2019 Facebook
+ #define STACK_MAX_LEN 600
+-/* clang will not unroll the loop 600 times.
+- * Instead it will unroll it to the amount it deemed
+- * appropriate, but the loop will still execute 600 times.
+- * Total program size is around 90k insns
++/* Full unroll of 600 iterations will have total
++ * program size close to 298k insns and this may
++ * cause BPF_JMP insn out of 16-bit integer range.
++ * So limit the unroll size to 150 so the
++ * total program size is around 80k insns but
++ * the loop will still execute 600 times.
+  */
++#define UNROLL_COUNT 150
+ #include "pyperf.h"
+-- 
+2.30.2
+

travis-ci/diffs/0001-selftests-bpf-fix-stacktrace_build_id-with-missing-k.diff

@@ -0,0 +1,43 @@
+From 0744fe5996e977b7a1634504b6a77426f6384bbe Mon Sep 17 00:00:00 2001
+From: Song Liu <song@kernel.org>
+Date: Thu, 26 May 2022 12:06:12 -0700
+Subject: [PATCH bpf] selftests/bpf: fix stacktrace_build_id with missing
+ kprobe/urandom_read
+
+Kernel function urandom_read is replaced with urandom_read_iter.
+Therefore, kprobe on urandom_read is not working any more:
+
+[root@eth50-1 bpf]# ./test_progs -n 161
+test_stacktrace_build_id:PASS:skel_open_and_load 0 nsec
+libbpf: kprobe perf_event_open() failed: No such file or directory
+libbpf: prog 'oncpu': failed to create kprobe 'urandom_read+0x0' \
+        perf event: No such file or directory
+libbpf: prog 'oncpu': failed to auto-attach: -2
+test_stacktrace_build_id:FAIL:attach_tp err -2
+161     stacktrace_build_id:FAIL
+
+Fix this by replacing urandom_read with urandom_read_iter in the test.
+
+Fixes: 1b388e7765f2 ("random: convert to using fops->read_iter()")
+Reported-by: Mykola Lysenko <mykolal@fb.com>
+Signed-off-by: Song Liu <song@kernel.org>
+---
+ tools/testing/selftests/bpf/progs/test_stacktrace_build_id.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/tools/testing/selftests/bpf/progs/test_stacktrace_build_id.c b/tools/testing/selftests/bpf/progs/test_stacktrace_build_id.c
+index 6c62bfb8bb6f..0c4426592a26 100644
+--- a/tools/testing/selftests/bpf/progs/test_stacktrace_build_id.c
++++ b/tools/testing/selftests/bpf/progs/test_stacktrace_build_id.c
+@@ -39,7 +39,7 @@ struct {
+ 	__type(value, stack_trace_t);
+ } stack_amap SEC(".maps");
+
+-SEC("kprobe/urandom_read")
++SEC("kprobe/urandom_read_iter")
+ int oncpu(struct pt_regs *args)
+ {
+ 	__u32 max_len = sizeof(struct bpf_stack_build_id)
+-- 
+2.30.2
+

travis-ci/vmtest/configs/blacklist/BLACKLIST-latest

@@ -0,0 +1,3 @@
+# TEMPORARY
+btf_dump/btf_dump: syntax
+kprobe_multi_test/bench_attach