Merge branch 'local-vmtest-enhancement-and-rv64-enabled'

Pu Lehui says:

====================
Local vmtest enhancement and RV64 enabled

Patch 1-3 fix some problem about bpf selftests. Patch 4 add local rootfs
image support for vmtest. Patch 5 enable cross-platform testing for
vmtest. Patch 6-10 enable vmtest on RV64.

We can now perform cross platform testing for riscv64 bpf using the
following command:

PLATFORM=riscv64 CROSS_COMPILE=riscv64-linux-gnu- \
  tools/testing/selftests/bpf/vmtest.sh \
  -l <path of local rootfs image> -- \
  ./test_progs -d \
      \"$(cat tools/testing/selftests/bpf/DENYLIST.riscv64 \
          | cut -d'#' -f1 \
          | sed -e 's/^[[:space:]]*//' \
                -e 's/[[:space:]]*$//' \
          | tr -s '\n' ',' \
      )\"

For better regression, we rely on commit [0]. And since the work of riscv
ftrace to remove stop_machine atomic replacement is in progress, we also
need to revert commit [1] [2].

The test platform is x86_64 architecture, and the versions of relevant
components are as follows:
    QEMU: 8.2.0
    CLANG: 17.0.6 (align to BPF CI)
    ROOTFS: ubuntu noble (generated by [3])

Link: https://lore.kernel.org/all/[email protected]/ [0]
Link: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=3308172276db [1]
Link: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=7caa9765465f [2]
Link: https://github.com/libbpf/ci/blob/main/rootfs/mkrootfs_debian.sh [3]

v3:
- Use llvm static linking when detecting that feature-llvm is enabled
- Add Acked-by by Eduard

v2: https://lore.kernel.org/all/[email protected]/
- Drop patch about relaxing Zbb insns restrictions.
- Add local rootfs image support
- Add description about running vmtest on RV64
- Fix some problem about bpf selftests

v1: https://lore.kernel.org/all/[email protected]/
====================

Acked-by: Daniel Borkmann <[email protected]>
Tested-by: Daniel Borkmann <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexei Starovoitov <[email protected]>

Author: Alexei Starovoitov

tools/testing/selftests/bpf/DENYLIST.riscv64

@@ -0,0 +1,3 @@
+# riscv64 deny list for BPF CI and local vmtest
+exceptions					# JIT does not support exceptions
+tailcalls/tailcall_bpf2bpf*			# JIT does not support mixing bpf2bpf and tailcalls

tools/testing/selftests/bpf/Makefile

@@ -187,20 +187,24 @@ FEATURE_TESTS := llvm
 FEATURE_DISPLAY := $(FEATURE_TESTS)
 
 # Makefile.feature expects OUTPUT to end with a slash
+ifeq ($(shell expr $(MAKE_VERSION) \>= 4.4), 1)
 $(let OUTPUT,$(OUTPUT)/,\
 	$(eval include ../../../build/Makefile.feature))
+else
+OUTPUT := $(OUTPUT)/
+$(eval include ../../../build/Makefile.feature)
+OUTPUT := $(patsubst %/,%,$(OUTPUT))
+endif
 endif
 
 ifeq ($(feature-llvm),1)
   LLVM_CFLAGS  += -DHAVE_LLVM_SUPPORT
   LLVM_CONFIG_LIB_COMPONENTS := mcdisassembler all-targets
   # both llvm-config and lib.mk add -D_GNU_SOURCE, which ends up as conflict
   LLVM_CFLAGS  += $(filter-out -D_GNU_SOURCE,$(shell $(LLVM_CONFIG) --cflags))
-  LLVM_LDLIBS  += $(shell $(LLVM_CONFIG) --libs $(LLVM_CONFIG_LIB_COMPONENTS))
-  ifeq ($(shell $(LLVM_CONFIG) --shared-mode),static)
-    LLVM_LDLIBS += $(shell $(LLVM_CONFIG) --system-libs $(LLVM_CONFIG_LIB_COMPONENTS))
-    LLVM_LDLIBS += -lstdc++
-  endif
+  LLVM_LDLIBS  += $(shell $(LLVM_CONFIG) --link-static --libs $(LLVM_CONFIG_LIB_COMPONENTS))
+  LLVM_LDLIBS  += $(shell $(LLVM_CONFIG) --link-static --system-libs $(LLVM_CONFIG_LIB_COMPONENTS))
+  LLVM_LDLIBS  += -lstdc++
   LLVM_LDFLAGS += $(shell $(LLVM_CONFIG) --ldflags)
 endif
 

tools/testing/selftests/bpf/README.rst

@@ -85,7 +85,37 @@ In case of linker errors when running selftests, try using static linking:
           If you want to change pahole and llvm, you can change `PATH` environment
           variable in the beginning of script.
 
-.. note:: The script currently only supports x86_64 and s390x architectures.
+Running vmtest on RV64
+======================
+To speed up testing and avoid various dependency issues, it is recommended to
+run vmtest in a Docker container. Before running vmtest, we need to prepare
+Docker container and local rootfs image. The overall steps are as follows:
+
+1. Create Docker container as shown in link [0].
+
+2. Use mkrootfs_debian.sh script [1] to build local rootfs image:
+
+.. code-block:: console
+
+  $ sudo ./mkrootfs_debian.sh --arch riscv64 --distro noble
+
+3. Start Docker container [0] and run vmtest in the container:
+
+.. code-block:: console
+
+  $ PLATFORM=riscv64 CROSS_COMPILE=riscv64-linux-gnu- \
+    tools/testing/selftests/bpf/vmtest.sh \
+    -l <path of local rootfs image> -- \
+    ./test_progs -d \
+        \"$(cat tools/testing/selftests/bpf/DENYLIST.riscv64 \
+            | cut -d'#' -f1 \
+            | sed -e 's/^[[:space:]]*//' \
+                  -e 's/[[:space:]]*$//' \
+            | tr -s '\n' ',' \
+        )\"
+
+Link: https://github.com/pulehui/riscv-bpf-vmtest.git [0]
+Link: https://github.com/libbpf/ci/blob/main/rootfs/mkrootfs_debian.sh [1]
 
 Additional information about selftest failures are
 documented here.

tools/testing/selftests/bpf/config.riscv64

@@ -0,0 +1,84 @@
+CONFIG_AUDIT=y
+CONFIG_BLK_CGROUP=y
+CONFIG_BLK_DEV_INITRD=y
+CONFIG_BLK_DEV_RAM=y
+CONFIG_BONDING=y
+CONFIG_BPF_JIT_ALWAYS_ON=y
+CONFIG_BPF_PRELOAD=y
+CONFIG_BPF_PRELOAD_UMD=y
+CONFIG_CGROUPS=y
+CONFIG_CGROUP_CPUACCT=y
+CONFIG_CGROUP_DEVICE=y
+CONFIG_CGROUP_FREEZER=y
+CONFIG_CGROUP_HUGETLB=y
+CONFIG_CGROUP_NET_CLASSID=y
+CONFIG_CGROUP_PERF=y
+CONFIG_CGROUP_PIDS=y
+CONFIG_CGROUP_SCHED=y
+CONFIG_CPUSETS=y
+CONFIG_DEBUG_ATOMIC_SLEEP=y
+CONFIG_DEBUG_FS=y
+CONFIG_DETECT_HUNG_TASK=y
+CONFIG_DEVTMPFS=y
+CONFIG_DEVTMPFS_MOUNT=y
+CONFIG_EXPERT=y
+CONFIG_EXT4_FS=y
+CONFIG_EXT4_FS_POSIX_ACL=y
+CONFIG_EXT4_FS_SECURITY=y
+CONFIG_FRAME_POINTER=y
+CONFIG_HARDLOCKUP_DETECTOR=y
+CONFIG_HIGH_RES_TIMERS=y
+CONFIG_HUGETLBFS=y
+CONFIG_INET=y
+CONFIG_IPV6_SEG6_LWTUNNEL=y
+CONFIG_IP_ADVANCED_ROUTER=y
+CONFIG_IP_MULTICAST=y
+CONFIG_IP_MULTIPLE_TABLES=y
+CONFIG_JUMP_LABEL=y
+CONFIG_KALLSYMS_ALL=y
+CONFIG_KPROBES=y
+CONFIG_MEMCG=y
+CONFIG_NAMESPACES=y
+CONFIG_NET=y
+CONFIG_NETDEVICES=y
+CONFIG_NETFILTER_XT_MATCH_BPF=y
+CONFIG_NET_ACT_BPF=y
+CONFIG_NET_L3_MASTER_DEV=y
+CONFIG_NET_VRF=y
+CONFIG_NONPORTABLE=y
+CONFIG_NO_HZ_IDLE=y
+CONFIG_NR_CPUS=256
+CONFIG_PACKET=y
+CONFIG_PANIC_ON_OOPS=y
+CONFIG_PARTITION_ADVANCED=y
+CONFIG_PCI=y
+CONFIG_PCI_HOST_GENERIC=y
+CONFIG_POSIX_MQUEUE=y
+CONFIG_PRINTK_TIME=y
+CONFIG_PROC_KCORE=y
+CONFIG_PROFILING=y
+CONFIG_RCU_CPU_STALL_TIMEOUT=60
+CONFIG_RISCV_EFFICIENT_UNALIGNED_ACCESS=y
+CONFIG_RISCV_ISA_C=y
+CONFIG_RISCV_PMU=y
+CONFIG_RISCV_PMU_SBI=y
+CONFIG_RT_GROUP_SCHED=y
+CONFIG_SECURITY_NETWORK=y
+CONFIG_SERIAL_8250=y
+CONFIG_SERIAL_8250_CONSOLE=y
+CONFIG_SERIAL_OF_PLATFORM=y
+CONFIG_SMP=y
+CONFIG_SOC_VIRT=y
+CONFIG_SYSVIPC=y
+CONFIG_TCP_CONG_ADVANCED=y
+CONFIG_TLS=y
+CONFIG_TMPFS=y
+CONFIG_TMPFS_POSIX_ACL=y
+CONFIG_TUN=y
+CONFIG_UNIX=y
+CONFIG_UPROBES=y
+CONFIG_USER_NS=y
+CONFIG_VETH=y
+CONFIG_VLAN_8021Q=y
+CONFIG_VSOCKETS_LOOPBACK=y
+CONFIG_XFRM_USER=y

tools/testing/selftests/bpf/prog_tests/bpf_tcp_ca.c

@@ -285,7 +285,7 @@ static void test_dctcp_fallback(void)
 	dctcp_skel = bpf_dctcp__open();
 	if (!ASSERT_OK_PTR(dctcp_skel, "dctcp_skel"))
 		return;
-	strcpy(dctcp_skel->rodata->fallback, "cubic");
+	strcpy(dctcp_skel->rodata->fallback_cc, "cubic");
 	if (!ASSERT_OK(bpf_dctcp__load(dctcp_skel), "bpf_dctcp__load"))
 		goto done;
 

tools/testing/selftests/bpf/progs/bpf_dctcp.c

@@ -26,7 +26,7 @@ static bool before(__u32 seq1, __u32 seq2)
 
 char _license[] SEC("license") = "GPL";
 
-volatile const char fallback[TCP_CA_NAME_MAX];
+volatile const char fallback_cc[TCP_CA_NAME_MAX];
 const char bpf_dctcp[] = "bpf_dctcp";
 const char tcp_cdg[] = "cdg";
 char cc_res[TCP_CA_NAME_MAX];
@@ -71,10 +71,10 @@ void BPF_PROG(bpf_dctcp_init, struct sock *sk)
 	struct bpf_dctcp *ca = inet_csk_ca(sk);
 	int *stg;
 
-	if (!(tp->ecn_flags & TCP_ECN_OK) && fallback[0]) {
+	if (!(tp->ecn_flags & TCP_ECN_OK) && fallback_cc[0]) {
 		/* Switch to fallback */
 		if (bpf_setsockopt(sk, SOL_TCP, TCP_CONGESTION,
-				   (void *)fallback, sizeof(fallback)) == -EBUSY)
+				   (void *)fallback_cc, sizeof(fallback_cc)) == -EBUSY)
 			ebusy_cnt++;
 
 		/* Switch back to myself and the recurred bpf_dctcp_init()
@@ -87,7 +87,7 @@ void BPF_PROG(bpf_dctcp_init, struct sock *sk)
 
 		/* Switch back to fallback */
 		if (bpf_setsockopt(sk, SOL_TCP, TCP_CONGESTION,
-				   (void *)fallback, sizeof(fallback)) == -EBUSY)
+				   (void *)fallback_cc, sizeof(fallback_cc)) == -EBUSY)
 			ebusy_cnt++;
 
 		/* Expecting -ENOTSUPP for tcp_cdg_res */