From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pf1-f173.google.com (mail-pf1-f173.google.com [209.85.210.173]) (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 7CB1F18B1A for ; Thu, 29 Aug 2024 02:01:58 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.173 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724896919; cv=none; b=dkQISyg2cZOogCF9+bbw9nuCuJegXiiylfGQLGuJAcngmA8DldKKslin44f7V0HotmE3qxnX2QoQVgVMKRnVMFciCCw0ctsPQsE6kfaKYQTNkaNt8SJSkUHZbXUYm1lGka6uzqyqgWIoFSqDFKec5ut9WfLR/zq2JEcyKqYTR/c= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724896919; c=relaxed/simple; bh=i2HwQ4kV2UPqCv0xLpqmcaKNSMAR/Sb0zJ0ougd6XZI=; h=Message-ID:Subject:From:To:Cc:Date:In-Reply-To:References: Content-Type:MIME-Version; b=ohcwtN2P0UPsl/EvW8bRE/b8j6NQDRQ55bSaG0XwXECIUybe1xiezzpVG93RHW6meJQRev9li2wbi3SrSFGd8yo+MQQXwq5aAecubudggMX717x6e821o80frBazCVgM3QavoGk+hD+uTLwMiUy6HPARCgrPV2OD6PTwOLHnUzI= 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=ZFboUv6a; arc=none smtp.client-ip=209.85.210.173 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="ZFboUv6a" Received: by mail-pf1-f173.google.com with SMTP id d2e1a72fcca58-7142a93ea9cso135019b3a.3 for ; Wed, 28 Aug 2024 19:01:58 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1724896918; x=1725501718; darn=vger.kernel.org; h=mime-version:user-agent:content-transfer-encoding:references :in-reply-to:date:cc:to:from:subject:message-id:from:to:cc:subject :date:message-id:reply-to; bh=cLAo3tq8o4aWru/snJc3as4ysvbwuMQs2aGtozb6tfA=; b=ZFboUv6aut1nwggz8mrgzBS17EnfcFs5btdCMVCVWUn/cYnPXla2q7r6Lf7kUzipgj EQOZoUkZFICoZvGXinOmu/dXhh41K3Nqi5CDEx248mXtohqKB+2bQjHNsw31WF2wI3ju 1cDIy3T9OVo/73XAcXObKvtKoZ39XBxkE1IDvC0rD7OYYh1tVfO6lYohTXih+7X+E8fn xgH30yai3dP6pL1xWb0GvqAyogoAwFPpe2KDyxDDzn7lQF7J3XC20Z8iDj3XxlD82ZBq 7Ir3noEPQ4DmVxbXVY1+BfZqgXK62cOGfZ5LaPsxc2iHACxsmmPAgeNKtW2kE+O/tcWt oJ8Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1724896918; x=1725501718; h=mime-version:user-agent:content-transfer-encoding:references :in-reply-to:date:cc:to:from:subject:message-id:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=cLAo3tq8o4aWru/snJc3as4ysvbwuMQs2aGtozb6tfA=; b=rWOW5iC7Z8oOeyamb6ckF+bA0uStF2ncp+N8ITbZyhV09nAcl6M30TZYlJdoRACqZ3 Ihx3ontoq/OUWzChtMAkz6G2aCXgesiQHCS4Jxr4JHtP703uo11w6mea/yJyASySwI/A ObnAia51bCQrnM/hXs9PJC4ztvF0es9c2DjBHlhXj12NadcTSxNYOTREhXzBKHvSYD6B QVhhV00Ol+jgzlzSVPOUKGVKUQgAqoIe4zJ37FGHc6udjRRsMBRhDrBJW8zQO8h0RNnX zcbLWdQiWoXf4Lu5+heS0PPd2SviTsr8s16BKZdUWTUPtt0QuMuQ6ZtfknysxzcCwpeX U75A== X-Forwarded-Encrypted: i=1; AJvYcCVJEaotAzKvvP+80tVOhjOhdENA1iK2v2Qjm2lrG+nQOLZgZakonFeFlVzJ0maerAtrp/g=@vger.kernel.org X-Gm-Message-State: AOJu0YyPVhaaXkzXI5fjgB5+9v4SK3lXIRQ0sj95rXD58q1AS1oIDVJv b6nmO4hp+yfBY3PDU8ngP8pHgQbMt+RxRmuWJHAqe2JEwybheitq X-Google-Smtp-Source: AGHT+IFCVrOW0KO3P0KiZ9OLkwhpCLFcPrp0RUKfh/XtsmyaGB+rHRWz7cMNu2M0jxCCKCdVNpk2EQ== X-Received: by 2002:a05:6a21:3997:b0:1ca:dafc:fbab with SMTP id adf61e73a8af0-1cce0feac73mr1774009637.4.1724896917626; Wed, 28 Aug 2024 19:01:57 -0700 (PDT) Received: from [192.168.0.235] ([38.34.87.7]) by smtp.gmail.com with ESMTPSA id d2e1a72fcca58-715e5749b3bsm124938b3a.187.2024.08.28.19.01.56 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 28 Aug 2024 19:01:57 -0700 (PDT) Message-ID: <488009642cac896a1f5aa30f39d897e484a9d5a8.camel@gmail.com> Subject: Re: [PATCH v4 bpf-next 2/9] bpf: Adjust BPF_JMP that jumps to the 1st insn of the prologue From: Eduard Zingerman To: Martin KaFai Lau , bpf@vger.kernel.org Cc: Alexei Starovoitov , Andrii Nakryiko , Daniel Borkmann , Yonghong Song , Amery Hung , kernel-team@meta.com Date: Wed, 28 Aug 2024 19:01:52 -0700 In-Reply-To: <20240827194834.1423815-3-martin.lau@linux.dev> References: <20240827194834.1423815-1-martin.lau@linux.dev> <20240827194834.1423815-3-martin.lau@linux.dev> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.52.4 (3.52.4-1.fc40) Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 On Tue, 2024-08-27 at 12:48 -0700, Martin KaFai Lau wrote: [...] > @@ -19705,6 +19705,9 @@ static int convert_ctx_accesses(struct bpf_verifi= er_env *env) > } > } > =20 > + if (delta) > + WARN_ON(adjust_jmp_off(env->prog, 0, delta, delta)); > + I double checked my old calculations and agree that this adjustment is nece= ssary. Alexei's suggestion to use delta =3D=3D skip_cnt sounds reasonable. > if (bpf_prog_is_offloaded(env->prog->aux)) > return 0; > =20 [...]