From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-qv1-f51.google.com (mail-qv1-f51.google.com [209.85.219.51]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 823002045AD for ; Fri, 17 Jul 2026 19:06:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.219.51 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784315184; cv=none; b=RFeTIPdtqgINI7VMvudKf5Garinc8QNvz6f/dq6YcKJzZtwJosTh7jNJ2QgxUQiIcNnE9GjWuX/+HtVFMrUSaho6iMJDTeIqv0oJcHXL7JQp/zn+QeC1yvOQmQW0/xxmYld4KI+Q0yxvXXxLNqfUX3rA3QBYJ93DEwo8m4It3JA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784315184; c=relaxed/simple; bh=nWMgcy9zH/zCGg85IYNWf4KjnH9+fNVSaaVmgPl1xDM=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=cIOF9QZ3EuW435x7ShJHwNbxKAO40zidl9zqQ2bKOtoGn9f9xF6FacstpNUB/hTXUw9UVxNVM+Xq8Yh68BQZijMowfNoSI76RhrPrXl/n6GBpJ/aqzTp9RD0eEUYrUfAiPgm/ZlG34T0ztCEqcrlLcfgstTGqlcMOrRtpulwtKo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=gkE3hNG2; arc=none smtp.client-ip=209.85.219.51 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="gkE3hNG2" Received: by mail-qv1-f51.google.com with SMTP id 6a1803df08f44-8ee6912d86dso35606696d6.1 for ; Fri, 17 Jul 2026 12:06:23 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1784315182; x=1784919982; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to:content-type; bh=ErOSeJ2Za9/1ZgC4ztqnYtsxKhikz8KNOMoALAHDxVY=; b=gkE3hNG2ux1nHj9OT+vByI94BA/1KfE4Vmxdqq8u9Eg7ScUJ1MNG8owDvs/Ni2BxP6 XxvrqYSapwhErJb+afcpCGpyjPI0kEUYu8QsJ5JDbElAgQaLAHBS2kFdDwzgw0BtFOnT VP/bIiMJ8Viq4UUyZhGq7iEIRWj5h6v/JmQYLZUw6MMnnfHfUnkw9l7AeppjszGOfiUb A34kDASA9mz3FHPU1xVcjYBm3izAhB/utLYg5yGW10hGXhed/2lD9BSAwGM4Kw1ltawp cPMlsSkifgh+yV+fKi5Z1EnnjY96hyDBYGnVgNIpi4sukB7AYHkaAKWcoXp7Z6okvjbo LDsA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1784315182; x=1784919982; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-gg:x-gm-message-state:from :to:cc:subject:date:message-id:reply-to:content-type; bh=ErOSeJ2Za9/1ZgC4ztqnYtsxKhikz8KNOMoALAHDxVY=; b=CQazWMFngCiXUDYoo9o+iVlM6yAParKrLzUV8E9rQ2e1PoeNjOhWThBEyaAifDeQnJ 4s+GO+RZovP2PSHyBP1L8GY08lMt81WjpRal1u9qmFXDTfLHjpoweKc67s7/xfoe8IYg 8UHhf/AhRqzHU0b/NQK/nxS2QrB1zSYOx9zplQ97JLtLSuo02TJGiDN9iltq9MDDiXJx 5lhMEY6IHLM73tS2CE9tmLgA+fsjsXkGAlCwStx1O2EKZ0zul/XRlQ55bHOchVsIxJmU UCl3T/VCdfLawdy1QEs4iLTWktVnUH7HoVSMmpYtnR92zNipEragDCOQ2sbNUbSk7Dmh 9hWw== X-Forwarded-Encrypted: i=1; AHgh+Ro+4BRSQyKDdXWsKMXmnALYlUDuFbU0IQ7++pVD7TJFdZDFbnnr+tVEqNjESJ78r/JCSPXwnbB6P1GJB/0=@vger.kernel.org X-Gm-Message-State: AOJu0YyjV41Dy9WkI6aNg26hhuWpvzJFzNqUKJHh+jE1oyyt8001sF89 vMiDaVVr+T8GAUgqInXQJyMRa5Ak7hZyvVzgGzphJAmguyDn3KOk7ANT X-Gm-Gg: AfdE7clMN6gxvsJmLZVF2Pd8xImVKQcKFQA8OD//Xz7+l3222B/FUb71hm915JJwNKP J3oGq+Zg5RR+xMOm1MNFjtzHDZbmHZ9b84qxscWStbj0dg9wgVZXfc9TjS+DEJNmY/aKdpiI4rp +HlKyuvnkZnpdYDfi28EUNDvDo7zxCVJAmKg04D/1ZX5dMj84sCQmNpbICP4tw4BXca43CaMm/y 3/WitUc6iWF/xD1h+rSpoFPq+9wRvN52JEwNgnRyuNSmvHBA+3yXM/NAnHCVyvMDt6kXGu52Xf0 U+GAsVybqkkNfBiaNiUw6xK8kDhDs3fwzYN5xQDHZtTQ5MisiY22YxX4oCfU+AeNRjKJAT/ctTA 3JtLMRtjgbTAVMljJ7QLTZARg2SrPRHtB2x0fcMNdAqeRZAG9XYew1FItHmVLBn87LUR2hiXmjW nnkaPeD+fc X-Received: by 2002:a05:6214:449e:b0:8fd:6de3:dd8b with SMTP id 6a1803df08f44-9077850ed21mr41084416d6.65.1784315182204; Fri, 17 Jul 2026 12:06:22 -0700 (PDT) Received: from TurinLinux.. ([184.144.109.221]) by smtp.gmail.com with ESMTPSA id 6a1803df08f44-9077871d06csm24035606d6.43.2026.07.17.12.06.19 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 17 Jul 2026 12:06:20 -0700 (PDT) From: Nicholas Dudar To: ast@kernel.org, daniel@iogearbox.net, andrii@kernel.org, eddyz87@gmail.com, memxor@gmail.com, deller@gmx.de, James.Bottomley@HansenPartnership.com Cc: bpf@vger.kernel.org, linux-parisc@vger.kernel.org, linux-kernel@vger.kernel.org, visitorckw@gmail.com Subject: [PATCH bpf-next 2/2] bpf, parisc: Add support for BPF_SDIV and BPF_SMOD in the parisc32 JIT Date: Fri, 17 Jul 2026 15:05:44 -0400 Message-Id: <20260717190544.257306-3-main.kalliope@gmail.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20260717190544.257306-1-main.kalliope@gmail.com> References: <20260717190544.257306-1-main.kalliope@gmail.com> Precedence: bulk X-Mailing-List: linux-parisc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit emit_alu_r32() and emit_alu_r64() call the unsigned millicode ($$divU/$$remU) and libgcc-style (hppa_div64()/hppa_div64_rem()) divide/remainder helpers for BPF_DIV and BPF_MOD regardless of the BPF instruction's signedness, so the parisc32 JIT does not implement signed BPF_SDIV and BPF_SMOD (off == 1). Signed ALU32 and ALU64 div/mod get an unsigned quotient and remainder rather than the verifier's and the interpreter's signed result for negative operands. Thread is_signed = (insn->off == 1) through emit_alu_r32()/ emit_alu_r64(), and on the signed path use the $$divI/$$remI signed millicode routines (32-bit) or the hppa_sdiv64()/hppa_sdiv64_rem() helpers added in patch 1 (64-bit) instead of their unsigned counterparts. $$divI and $$remI are extern-declared and exported next to $$divU/$$remU in arch/parisc/kernel/parisc_ksyms.c. bpf_do_misc_fixups() rewrites the zero-divisor and INT_MIN/-1 cases out of the instruction stream before the JIT runs. Signed-off-by: Nicholas Dudar Assisted-by: Claude:claude-opus-4-8 --- arch/parisc/net/bpf_jit_comp32.c | 29 +++++++++++++++++++---------- 1 file changed, 19 insertions(+), 10 deletions(-) diff --git a/arch/parisc/net/bpf_jit_comp32.c b/arch/parisc/net/bpf_jit_comp32.c index 5ff0cf925fe9..eea0a34a3bfe 100644 --- a/arch/parisc/net/bpf_jit_comp32.c +++ b/arch/parisc/net/bpf_jit_comp32.c @@ -321,6 +321,8 @@ static void bpf_put_reg32(const s8 *reg, const s8 *src, extern void $$mulI(void); extern void $$divU(void); extern void $$remU(void); +extern void $$divI(void); +extern void $$remI(void); static void emit_call_millicode(void *func, const s8 arg0, const s8 arg1, u8 opcode, struct hppa_jit_context *ctx) @@ -562,12 +564,14 @@ static void emit_alu_i32(const s8 *dst, s32 imm, } static void emit_alu_r64(const s8 *dst, const s8 *src, - struct hppa_jit_context *ctx, const u8 op) + struct hppa_jit_context *ctx, const u8 op, + bool is_signed) { const s8 *tmp1 = regmap[TMP_REG_1]; const s8 *tmp2 = regmap[TMP_REG_2]; const s8 *rd; const s8 *rs = bpf_get_reg64(src, tmp2, ctx); + void *func; if (op == BPF_MOV) rd = bpf_get_reg64_ref(dst, tmp1, false, ctx); @@ -604,10 +608,12 @@ static void emit_alu_r64(const s8 *dst, const s8 *src, emit_call_libgcc_ll(__muldi3, rd, rs, op, ctx); break; case BPF_DIV: - emit_call_libgcc_ll(&hppa_div64, rd, rs, op, ctx); + func = is_signed ? &hppa_sdiv64 : &hppa_div64; + emit_call_libgcc_ll(func, rd, rs, op, ctx); break; case BPF_MOD: - emit_call_libgcc_ll(&hppa_div64_rem, rd, rs, op, ctx); + func = is_signed ? &hppa_sdiv64_rem : &hppa_div64_rem; + emit_call_libgcc_ll(func, rd, rs, op, ctx); break; case BPF_LSH: emit_call_libgcc_ll(__ashldi3, rd, rs, op, ctx); @@ -630,7 +636,8 @@ static void emit_alu_r64(const s8 *dst, const s8 *src, } static void emit_alu_r32(const s8 *dst, const s8 *src, - struct hppa_jit_context *ctx, const u8 op) + struct hppa_jit_context *ctx, const u8 op, + bool is_signed) { const s8 *tmp1 = regmap[TMP_REG_1]; const s8 *tmp2 = regmap[TMP_REG_2]; @@ -666,10 +673,12 @@ static void emit_alu_r32(const s8 *dst, const s8 *src, emit_call_millicode($$mulI, lo(rd), lo(rs), op, ctx); break; case BPF_DIV: - emit_call_millicode($$divU, lo(rd), lo(rs), op, ctx); + emit_call_millicode(is_signed ? $$divI : $$divU, + lo(rd), lo(rs), op, ctx); break; case BPF_MOD: - emit_call_millicode($$remU, lo(rd), lo(rs), op, ctx); + emit_call_millicode(is_signed ? $$remI : $$remU, + lo(rd), lo(rs), op, ctx); break; case BPF_LSH: emit(hppa_subi(0x1f, lo(rs), HPPA_REG_T0), ctx); @@ -1163,12 +1172,12 @@ int bpf_jit_emit_insn(const struct bpf_insn *insn, struct hppa_jit_context *ctx, emit_imm32(tmp2, imm, ctx); src = tmp2; } - emit_alu_r64(dst, src, ctx, BPF_OP(code)); + emit_alu_r64(dst, src, ctx, BPF_OP(code), off == 1); break; /* dst = -dst */ case BPF_ALU64 | BPF_NEG: - emit_alu_r64(dst, tmp2, ctx, BPF_OP(code)); + emit_alu_r64(dst, tmp2, ctx, BPF_OP(code), false); break; case BPF_ALU64 | BPF_MOV | BPF_K: @@ -1211,7 +1220,7 @@ int bpf_jit_emit_insn(const struct bpf_insn *insn, struct hppa_jit_context *ctx, emit_imm32(tmp2, imm, ctx); src = tmp2; } - emit_alu_r32(dst, src, ctx, BPF_OP(code)); + emit_alu_r32(dst, src, ctx, BPF_OP(code), off == 1); break; /* dst = dst OP imm */ @@ -1236,7 +1245,7 @@ int bpf_jit_emit_insn(const struct bpf_insn *insn, struct hppa_jit_context *ctx, * src is ignored---choose tmp2 as a dummy register since it * is not on the stack. */ - emit_alu_r32(dst, tmp2, ctx, BPF_OP(code)); + emit_alu_r32(dst, tmp2, ctx, BPF_OP(code), false); break; /* dst = BSWAP##imm(dst) */ -- 2.34.1