On 2021/11/3 21:15, Daniel Borkmann wrote:
On 11/3/21 12:54 PM, Björn Töpel wrote:Commit 252c765bd764 ("riscv, bpf: Add BPF exception tables") only addressed RV64, and broke the RV32 build [1]. Fix by gating the exception tables code with CONFIG_ARCH_RV64I. Further, silence a "-Wmissing-prototypes" warning [2] in the RV64 BPF JIT. [1] https://lore.kernel.org/llvm/202111020610.9oy9Rr0G-lkp@xxxxxxxxx/ [2] https://lore.kernel.org/llvm/202110290334.2zdMyRq4-lkp@xxxxxxxxx/ Fixes: 252c765bd764 ("riscv, bpf: Add BPF exception tables") Signed-off-by: Björn Töpel <bjorn@xxxxxxxxxx> --- Tong/Daniel: The RV32 build has been broken since Thursday. I'll try to fast-track a bit, and commit a quick-fix for it. Hope that's OK with you, Tong! I've verified the build on my machine using riscv32 GCC 9.3.0 and riscv64 GCC 11.2.0.Thanks for the fix Bjorn!arch/riscv/mm/extable.c | 4 ++-- arch/riscv/net/bpf_jit_comp64.c | 2 ++ 2 files changed, 4 insertions(+), 2 deletions(-) diff --git a/arch/riscv/mm/extable.c b/arch/riscv/mm/extable.c index 18bf338303b6..ddb7d3b99e89 100644 --- a/arch/riscv/mm/extable.c +++ b/arch/riscv/mm/extable.c @@ -11,7 +11,7 @@ #include <linux/module.h> #include <linux/uaccess.h> -#ifdef CONFIG_BPF_JIT +#if defined(CONFIG_BPF_JIT) && defined(CONFIG_ARCH_RV64I) int rv_bpf_fixup_exception(const struct exception_table_entry *ex, struct pt_regs *regs); #endif @@ -23,7 +23,7 @@ int fixup_exception(struct pt_regs *regs) if (!fixup) return 0; -#ifdef CONFIG_BPF_JIT +#if defined(CONFIG_BPF_JIT) && defined(CONFIG_ARCH_RV64I) if (regs->epc >= BPF_JIT_REGION_START && regs->epc < BPF_JIT_REGION_END) return rv_bpf_fixup_exception(fixup, regs); #endif diff --git a/arch/riscv/net/bpf_jit_comp64.c b/arch/riscv/net/bpf_jit_comp64.c index 2ca345c7b0bf..f2a779c7e225 100644 --- a/arch/riscv/net/bpf_jit_comp64.c +++ b/arch/riscv/net/bpf_jit_comp64.c @@ -459,6 +459,8 @@ static int emit_call(bool fixed, u64 addr, struct rv_jit_context *ctx) #define BPF_FIXUP_OFFSET_MASK GENMASK(26, 0) #define BPF_FIXUP_REG_MASK GENMASK(31, 27) +int rv_bpf_fixup_exception(const struct exception_table_entry *ex, + struct pt_regs *regs);I'm okay to take this as a quick fix, but if its not too much hassle, could we add a arch/riscv/include/asm/extable.h in similar fashion like arm64 or x86 where we move the ex_handler_bpf() signature there, did you have a chance to check?
Hi Daniel: On the question of whether to add asm/extable.h, I have an in-depth discussion with Björn, both schemes are OK. This patch is the scheme of adding a header file: https://lore.kernel.org/bpf/20211102145642.724820-1-tongtiangen@xxxxxxxxxx/ Reviewed-by: Tong Tiangen <tongtiangen@xxxxxxxxxx> Thanks.
int rv_bpf_fixup_exception(const struct exception_table_entry *ex, struct pt_regs *regs) { base-commit: cc0356d6a02e064387c16a83cb96fe43ef33181eThanks, Daniel .
