Merge branch 'bpf-riscv-jit'

Björn Töpel says: ==================== This v2 series adds an RV64G BPF JIT to the kernel. At the moment the RISC-V Linux port does not support CONFIG_HAVE_KPROBES (Patrick Stählin sent out an RFC last year), which means that CONFIG_BPF_EVENTS is not supported. Thus, no tests involving BPF_PROG_TYPE_TRACEPOINT, BPF_PROG_TYPE_PERF_EVENT, BPF_PROG_TYPE_KPROBE and BPF_PROG_TYPE_RAW_TRACEPOINT passes. The implementation does not support "far branching" (>4KiB). Test results: # modprobe test_bpf test_bpf: Summary: 378 PASSED, 0 FAILED, [366/366 JIT'ed] # echo 1 > /proc/sys/kernel/unprivileged_bpf_disabled # ./test_verifier ... Summary: 761 PASSED, 507 SKIPPED, 2 FAILED Note that "test_verifier" was run with one build with CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS=y and one without, otherwise many of the the tests that require unaligned access were skipped. CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS=y: # echo 1 > /proc/sys/kernel/unprivileged_bpf_disabled # ./test_verifier | grep -c 'NOTE.*unknown align' 0 No CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS: # echo 1 > /proc/sys/kernel/unprivileged_bpf_disabled # ./test_verifier | grep -c 'NOTE.*unknown align' 59 The two failing test_verifier tests are: "ld_abs: vlan + abs, test 1" "ld_abs: jump around ld_abs" This is due to that "far branching" involved in those tests. All tests where done on QEMU emulator version 3.1.50 (v3.1.0-688-g8ae951fbc106). I'll test it on real hardware, when I get access to it. I'm routing this patch via bpf-next/netdev mailing list (after a conversation with Palmer at FOSDEM), mainly because the other JITs went that path. Again, thanks for all the comments! Cheers, Björn v1 -> v2: * Added JMP32 support. (Daniel) * Add RISC-V to Documentation/sysctl/net.txt. (Daniel) * Fixed seen_call() asymmetry. (Daniel) * Fixed broken bpf_flush_icache() range. (Daniel) * Added alignment annotations to some selftests. RFCv1 -> v1: * Cleaned up the Kconfig and net/Makefile. (Christoph) * Removed the entry-stub and squashed the build/config changes to be part of the JIT implementation. (Christoph) * Simplified the register tracking code. (Daniel) * Removed unused macros. (Daniel) * Added myself as maintainer and updated documentation. (Daniel) * Removed HAVE_EFFICIENT_UNALIGNED_ACCESS. (Christoph, Palmer) * Added tail-calls and cleaned up the code. ==================== Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
mariux64 · Feb 5, 2019 · 90d304b · 90d304b
2 parents 31de389 + e2c6f50
commit 90d304b
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diff --git a/Documentation/networking/filter.txt b/Documentation/networking/filter.txt
@@ -464,10 +464,11 @@ breakpoints: 0 1
 JIT compiler
 ------------
 
-The Linux kernel has a built-in BPF JIT compiler for x86_64, SPARC, PowerPC,
-ARM, ARM64, MIPS and s390 and can be enabled through CONFIG_BPF_JIT. The JIT
-compiler is transparently invoked for each attached filter from user space
-or for internal kernel users if it has been previously enabled by root:
+The Linux kernel has a built-in BPF JIT compiler for x86_64, SPARC,
+PowerPC, ARM, ARM64, MIPS, RISC-V and s390 and can be enabled through
+CONFIG_BPF_JIT. The JIT compiler is transparently invoked for each
+attached filter from user space or for internal kernel users if it has
+been previously enabled by root:
 
   echo 1 > /proc/sys/net/core/bpf_jit_enable
 
@@ -603,9 +604,10 @@ got from bpf_prog_create(), and 'ctx' the given context (e.g.
 skb pointer). All constraints and restrictions from bpf_check_classic() apply
 before a conversion to the new layout is being done behind the scenes!
 
-Currently, the classic BPF format is being used for JITing on most 32-bit
-architectures, whereas x86-64, aarch64, s390x, powerpc64, sparc64, arm32 perform
-JIT compilation from eBPF instruction set.
+Currently, the classic BPF format is being used for JITing on most
+32-bit architectures, whereas x86-64, aarch64, s390x, powerpc64,
+sparc64, arm32, riscv (RV64G) perform JIT compilation from eBPF
+instruction set.
 
 Some core changes of the new internal format:
 

diff --git a/Documentation/sysctl/net.txt b/Documentation/sysctl/net.txt
@@ -52,6 +52,7 @@ two flavors of JITs, the newer eBPF JIT currently supported on:
   - sparc64
   - mips64
   - s390x
+  - riscv
 
 And the older cBPF JIT supported on the following archs:
   - mips

diff --git a/MAINTAINERS b/MAINTAINERS
@@ -2907,6 +2907,12 @@ L:	netdev@vger.kernel.org
 S:	Maintained
 F:	arch/powerpc/net/
 
+BPF JIT for RISC-V (RV64G)
+M:	Björn Töpel <bjorn.topel@gmail.com>
+L:	netdev@vger.kernel.org
+S:	Maintained
+F:	arch/riscv/net/
+
 BPF JIT for S390
 M:	Martin Schwidefsky <schwidefsky@de.ibm.com>
 M:	Heiko Carstens <heiko.carstens@de.ibm.com>

diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
@@ -49,6 +49,7 @@ config RISCV
 	select RISCV_TIMER
 	select GENERIC_IRQ_MULTI_HANDLER
 	select ARCH_HAS_PTE_SPECIAL
+	select HAVE_EBPF_JIT if 64BIT
 
 config MMU
 	def_bool y

diff --git a/arch/riscv/Makefile b/arch/riscv/Makefile
@@ -77,7 +77,7 @@ KBUILD_IMAGE	:= $(boot)/Image.gz
 
 head-y := arch/riscv/kernel/head.o
 
-core-y += arch/riscv/kernel/ arch/riscv/mm/
+core-y += arch/riscv/kernel/ arch/riscv/mm/ arch/riscv/net/
 
 libs-y += arch/riscv/lib/
 

diff --git a/arch/riscv/net/Makefile b/arch/riscv/net/Makefile
@@ -0,0 +1 @@
+obj-$(CONFIG_BPF_JIT) += bpf_jit_comp.o