From patchwork Fri Mar 8 01:08:00 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexei Starovoitov X-Patchwork-Id: 13586392 X-Patchwork-Delegate: bpf@iogearbox.net Received: from mail-pf1-f172.google.com (mail-pf1-f172.google.com [209.85.210.172]) (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 DAD7E21342 for ; Fri, 8 Mar 2024 01:08:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.172 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709860106; cv=none; b=Sjd5lISdPOsWKZwMUy3uF9A853hU/ZQerS5/zVfm1uNOv6qDM/f+kaIDgOpqHi/lVq9numVu3b8lGbAmo+STz/RHkM6O34H9RJJkLNEjvlRoL7qBZ0ffcEz4JQA8FjK3EKbe/oLWNX9nss4ukcZwkyf4vnvAiQtiO+vNqiImVpg= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709860106; c=relaxed/simple; bh=S9sDfSIwZFp6TuxY/d/HaiqfOfARsWKaqoJtVBSEc3Y=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=N/+jEGq0dQo7S76umjdeLRnPEejh2jbwURcqFhMQf5JNH+ahoZQNda2rMhgjoTsDgqVht2zz6UTaq422HmGVnwSbE+PbglDtcvebPwTivgeGVOzgIUh42j/wctvSom12ReIC+7xOo2D3ka71DQFctJmvKSw1ybOCc4oihAtaLxc= 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=hRhBL7UX; arc=none smtp.client-ip=209.85.210.172 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="hRhBL7UX" Received: by mail-pf1-f172.google.com with SMTP id d2e1a72fcca58-6e617b39877so1295698b3a.3 for ; Thu, 07 Mar 2024 17:08:24 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1709860103; x=1710464903; 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; bh=eol0rLj8ZVaqzxemLtYqGJLGqcrhD/N/8xdUYrW35uM=; b=hRhBL7UXB03GPlGDE6V4BIZFoYC4MICmsPj2LKxRsaYIxp4wwViD6DfMlq+s5vLADs 5sm1+djTxwQKJKchJ45F0bQ4q45zdCxPiytqTFUdQZi5ODgrlpWOZV0vYTCbZf0ZpJ45 /y0kStWtnoM3nM2F0n8BxiCPujsflaSwlfQI6caE/02QGv3IZ5myZUe7l+9z6+WxmXNj 78WPw2xKCXFxPJ9kKMOY2KZ+7niC25cceiTuVW6+QszmVqsLUphtXFKBJC8lWX/4PpS9 dPyz4RvWZ04SPk5QRiLOfnHMPF6WtJ6uy6tJ6H+fTyRDtfram24dm1kLq25MsNxC82Er Oltg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1709860103; x=1710464903; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=eol0rLj8ZVaqzxemLtYqGJLGqcrhD/N/8xdUYrW35uM=; b=U/GZ6tVQ2QTzi5VqelU3V1mkt4ExPPFgrCu4ZBIEfUjPhIMMZ5pp2tlpgh+RpkdsTt j8KOPFslSL5N7n0o8Q3twjmafjYR+jy7tIQhTHqlVzOthvo5Adqwv5bX39pjN8ku2qbX lHwH3sSI3Qv9qMQUFhDr30p3yJwrZD9GcLWBDt9R2nK363YhPTVC7lqxJe+IrenA3PG7 HrMZZbPrt/IjELTPMgBDM6PA1Tx8fUtWbg6nrcfjmWpTm6VDjtBJ/prVUEsL99YBAMVb UWARyKypLixyAVh25+4Ndc681wtUycDtoJzw0HK5rH7MA0SjxsrX+m2XJE8Iw2VCuMaW /MOA== X-Gm-Message-State: AOJu0YyBnzfltCBWbYgEh04vlgMVZoPZ4JhZfk00zLRF179/BDZu3ru1 +FNMDAuSSvM/ppaQurTaWzJmtl0SLAfbmxAoFYqRRHOdMCNB1rDon7SlyvAC X-Google-Smtp-Source: AGHT+IEVuK7WXVcuZMt8VNUGYBFGky0WlIL+If2MnPNUNirTnV2pe36+CiCA+QDit7CvlPgNYZps4g== X-Received: by 2002:a05:6a20:6a1c:b0:1a1:6f1b:90f1 with SMTP id p28-20020a056a206a1c00b001a16f1b90f1mr4702201pzk.1.1709860103430; Thu, 07 Mar 2024 17:08:23 -0800 (PST) Received: from localhost.localdomain ([2620:10d:c090:400::5:428c]) by smtp.gmail.com with ESMTPSA id gu19-20020a056a004e5300b006e6499d9c03sm3914096pfb.197.2024.03.07.17.08.22 (version=TLS1_3 cipher=TLS_CHACHA20_POLY1305_SHA256 bits=256/256); Thu, 07 Mar 2024 17:08:23 -0800 (PST) From: Alexei Starovoitov To: bpf@vger.kernel.org Cc: daniel@iogearbox.net, andrii@kernel.org, torvalds@linux-foundation.org, brho@google.com, hannes@cmpxchg.org, akpm@linux-foundation.org, urezki@gmail.com, hch@infradead.org, linux-mm@kvack.org, kernel-team@fb.com Subject: [PATCH v3 bpf-next 02/14] bpf: Disasm support for addr_space_cast instruction. Date: Thu, 7 Mar 2024 17:08:00 -0800 Message-Id: <20240308010812.89848-3-alexei.starovoitov@gmail.com> X-Mailer: git-send-email 2.39.3 (Apple Git-145) In-Reply-To: <20240308010812.89848-1-alexei.starovoitov@gmail.com> References: <20240308010812.89848-1-alexei.starovoitov@gmail.com> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Patchwork-Delegate: bpf@iogearbox.net From: Alexei Starovoitov LLVM generates rX = addr_space_cast(rY, dst_addr_space, src_addr_space) instruction when pointers in non-zero address space are used by the bpf program. Recognize this insn in uapi and in bpf disassembler. Acked-by: Kumar Kartikeya Dwivedi Signed-off-by: Alexei Starovoitov --- include/uapi/linux/bpf.h | 4 ++++ kernel/bpf/disasm.c | 10 ++++++++++ tools/include/uapi/linux/bpf.h | 4 ++++ 3 files changed, 18 insertions(+) diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index e30d943db8a4..3c42b9f1bada 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -1339,6 +1339,10 @@ enum { */ #define BPF_PSEUDO_KFUNC_CALL 2 +enum bpf_addr_space_cast { + BPF_ADDR_SPACE_CAST = 1, +}; + /* flags for BPF_MAP_UPDATE_ELEM command */ enum { BPF_ANY = 0, /* create new element or update existing */ diff --git a/kernel/bpf/disasm.c b/kernel/bpf/disasm.c index 82b2dbdd048f..bd2e2dd04740 100644 --- a/kernel/bpf/disasm.c +++ b/kernel/bpf/disasm.c @@ -166,6 +166,12 @@ static bool is_movsx(const struct bpf_insn *insn) (insn->off == 8 || insn->off == 16 || insn->off == 32); } +static bool is_addr_space_cast(const struct bpf_insn *insn) +{ + return insn->code == (BPF_ALU64 | BPF_MOV | BPF_X) && + insn->off == BPF_ADDR_SPACE_CAST; +} + void print_bpf_insn(const struct bpf_insn_cbs *cbs, const struct bpf_insn *insn, bool allow_ptr_leaks) @@ -184,6 +190,10 @@ void print_bpf_insn(const struct bpf_insn_cbs *cbs, insn->code, class == BPF_ALU ? 'w' : 'r', insn->dst_reg, class == BPF_ALU ? 'w' : 'r', insn->dst_reg); + } else if (is_addr_space_cast(insn)) { + verbose(cbs->private_data, "(%02x) r%d = addr_space_cast(r%d, %d, %d)\n", + insn->code, insn->dst_reg, + insn->src_reg, ((u32)insn->imm) >> 16, (u16)insn->imm); } else if (BPF_SRC(insn->code) == BPF_X) { verbose(cbs->private_data, "(%02x) %c%d %s %s%c%d\n", insn->code, class == BPF_ALU ? 'w' : 'r', diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index e30d943db8a4..3c42b9f1bada 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -1339,6 +1339,10 @@ enum { */ #define BPF_PSEUDO_KFUNC_CALL 2 +enum bpf_addr_space_cast { + BPF_ADDR_SPACE_CAST = 1, +}; + /* flags for BPF_MAP_UPDATE_ELEM command */ enum { BPF_ANY = 0, /* create new element or update existing */