From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id CFD812D3A69; Mon, 13 Apr 2026 12:33:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776083614; cv=none; b=ONszNG9TnDsGnpFH8kLxPX8x27D+mophqJPiJNGyRTvq+8mAQMJpWlXfBXb9SFPXmtGLZm8uvEwQ6qbyv6G7/TzLdCFpWlRpJ+Dx9gtWqVfjDTpQFnPShBVWKIW9uf3wgYn7+MIv49HftrT8VpGEfQgyvao2fN5tlCwQiv4KMQk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776083614; c=relaxed/simple; bh=s2vi1gMOe/zR29r19y5FbZV0U3O5/J47TujbBaojO2Q=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=jwLYwhHn2neM+x6/9/r/IhlxiECnxxkqGzu+RctMmgWyaekKSEVJtolHz+ec5W7NvQBv/+K4uxWFWI5qTjqRvKVuWTZSEq6sLYdX3yZt4gbIvFX4Iq3uEc5H+bHDm7TFR+ox2hjrPqWZ0y/KwzysnFkyUwNng2NK8pfutU3+CpY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=tyVdMkfK; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="tyVdMkfK" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5C778C2BCAF; Mon, 13 Apr 2026 12:33:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1776083614; bh=s2vi1gMOe/zR29r19y5FbZV0U3O5/J47TujbBaojO2Q=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=tyVdMkfK4Oedgp2gw/N++DpkgaKb8l8tqh6RNQQu+m78z4PZX76lWAkk7uCa7uTzw WjO4QNoNAx8PaoFPUDio7r7lHUblHPTnjKE+CSKp2IFpaRCr2O7H7qA+Ov33NVq9/7 6oqMi2QvgGZ6rInIBaUEcu4wIsjD+tRbVYAmw6sIJvml1IF7ow6rvdRSr3DOLeIk1J Gx72Cfs3ZAm26IK48vwf1zqZr1sSng05KRjk1fpTRty7IiznAstw4qSYj016I6PnKz iggPuonwpdFCEul7W4eCW05XVHjsdAQq5jw6sisOiWjot2aosVsu/Oa7PqOLokO80m TiydTUzKdzQkw== From: Puranjay Mohan To: bpf@vger.kernel.org Cc: Puranjay Mohan , Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Martin KaFai Lau , Eduard Zingerman , Kumar Kartikeya Dwivedi , Song Liu , Yonghong Song , Jiri Olsa , Xu Kuohai , Catalin Marinas , Will Deacon , Luke Nelson , Xi Wang , =?UTF-8?q?Bj=C3=B6rn=20T=C3=B6pel?= , Pu Lehui , Paul Walmsley , Palmer Dabbelt , Albert Ou , Alexandre Ghiti , linux-arm-kernel@lists.infradead.org, linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org Subject: [PATCH bpf-next 2/2] bpf, riscv: Remove redundant bpf_flush_icache() after pack allocator finalize Date: Mon, 13 Apr 2026 05:32:55 -0700 Message-ID: <20260413123256.3296452-3-puranjay@kernel.org> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20260413123256.3296452-1-puranjay@kernel.org> References: <20260413123256.3296452-1-puranjay@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit bpf_flush_icache() calls flush_icache_range() to clean the data cache and invalidate the instruction cache for the JITed code region. However, since commit 48a8f78c50bd ("bpf, riscv: use prog pack allocator in the BPF JIT"), this flush is redundant. bpf_jit_binary_pack_finalize() copies the JITed instructions to the ROX region via bpf_arch_text_copy() -> patch_text_nosync(), and patch_text_nosync() already calls flush_icache_range() on the written range. The subsequent bpf_flush_icache() repeats the same cache maintenance on an overlapping range. Remove the redundant bpf_flush_icache() call and its now-unused definition. Fixes: 48a8f78c50bd ("bpf, riscv: use prog pack allocator in the BPF JIT") Signed-off-by: Puranjay Mohan --- arch/riscv/net/bpf_jit.h | 5 ----- arch/riscv/net/bpf_jit_core.c | 7 ------- 2 files changed, 12 deletions(-) diff --git a/arch/riscv/net/bpf_jit.h b/arch/riscv/net/bpf_jit.h index 632ced07bca4..549537cad86b 100644 --- a/arch/riscv/net/bpf_jit.h +++ b/arch/riscv/net/bpf_jit.h @@ -105,11 +105,6 @@ static inline void bpf_fill_ill_insns(void *area, unsigned int size) memset(area, 0, size); } -static inline void bpf_flush_icache(void *start, void *end) -{ - flush_icache_range((unsigned long)start, (unsigned long)end); -} - /* Emit a 4-byte riscv instruction. */ static inline void emit(const u32 insn, struct rv_jit_context *ctx) { diff --git a/arch/riscv/net/bpf_jit_core.c b/arch/riscv/net/bpf_jit_core.c index b3581e926436..f7fd4afc3ca3 100644 --- a/arch/riscv/net/bpf_jit_core.c +++ b/arch/riscv/net/bpf_jit_core.c @@ -183,13 +183,6 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog) prog = orig_prog; goto out_offset; } - /* - * The instructions have now been copied to the ROX region from - * where they will execute. - * Write any modified data cache blocks out to memory and - * invalidate the corresponding blocks in the instruction cache. - */ - bpf_flush_icache(jit_data->ro_header, ctx->ro_insns + ctx->ninsns); for (i = 0; i < prog->len; i++) ctx->offset[i] = ninsns_rvoff(ctx->offset[i]); bpf_prog_fill_jited_linfo(prog, ctx->offset); -- 2.52.0