From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id C39CFC4829E for ; Tue, 13 Feb 2024 00:49:07 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 58BEA6B0083; Mon, 12 Feb 2024 19:49:07 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 5144A6B0087; Mon, 12 Feb 2024 19:49:07 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 38FCE6B0088; Mon, 12 Feb 2024 19:49:07 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) by kanga.kvack.org (Postfix) with ESMTP id 230766B0083 for ; Mon, 12 Feb 2024 19:49:07 -0500 (EST) Received: from smtpin20.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay05.hostedemail.com (Postfix) with ESMTP id 0002D40B3F for ; Tue, 13 Feb 2024 00:49:06 +0000 (UTC) X-FDA: 81784946292.20.43B695B Received: from mail-ej1-f54.google.com (mail-ej1-f54.google.com [209.85.218.54]) by imf15.hostedemail.com (Postfix) with ESMTP id F2DC7A0012 for ; Tue, 13 Feb 2024 00:49:04 +0000 (UTC) Authentication-Results: imf15.hostedemail.com; dkim=pass header.d=gmail.com header.s=20230601 header.b=NidztkzY; spf=pass (imf15.hostedemail.com: domain of eddyz87@gmail.com designates 209.85.218.54 as permitted sender) smtp.mailfrom=eddyz87@gmail.com; dmarc=pass (policy=none) header.from=gmail.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1707785345; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=/dwE/gJs3UjhLkiVxd8ovvyGICgHNTOI+7wm4P8nOQE=; b=PdypdE1nQ/h08nM0hFWDjNkeSAwrl2ZvYmLYd1cxODpzNTeAZzQ/cF6diLcK3UFb0uZDXD iYRbFL0WirfJVsW2lrh7DoZXmK5U7Nn5X/p7Xmgo/BXOqXQzdWRmzm8wN72vLHF1KmaEHL 8foLWt9MfVZdIu6HxnairRU3Wm97Pf0= ARC-Authentication-Results: i=1; imf15.hostedemail.com; dkim=pass header.d=gmail.com header.s=20230601 header.b=NidztkzY; spf=pass (imf15.hostedemail.com: domain of eddyz87@gmail.com designates 209.85.218.54 as permitted sender) smtp.mailfrom=eddyz87@gmail.com; dmarc=pass (policy=none) header.from=gmail.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1707785345; a=rsa-sha256; cv=none; b=Km5crz4EdcpmXKbaxCBzCLY3Yj087oHE2pcouXxgJTBIFq3s0t/6X5zeOGobQjEKFsgI0i b0jYMmkenCF7VUBVC3yNzy90SxvS3p9WDA87KiFkB86y5/HlmZNFFcKEStXjjT8Uyx4m2e /IvtnDWACtWFHz8i+8Qf/pAPeSfnx30= Received: by mail-ej1-f54.google.com with SMTP id a640c23a62f3a-a3ccea0d75fso126446266b.1 for ; Mon, 12 Feb 2024 16:49:04 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1707785343; x=1708390143; darn=kvack.org; h=mime-version:user-agent:content-transfer-encoding:autocrypt :references:in-reply-to:date:cc:to:from:subject:message-id:from:to :cc:subject:date:message-id:reply-to; bh=/dwE/gJs3UjhLkiVxd8ovvyGICgHNTOI+7wm4P8nOQE=; b=NidztkzY0vihGfn+zg7qfsdVPLKzx5ZdmG12Sm9B7dPszKUxNWO8XKGMVjnXfXWkzd GW1xcUD4w/Th3gwv5KxORou9Urlxhb7DFWkOBb5RG44naDj/sX1bcZW6SVyJc+D6mmRr roLLP6HjSf2NDJLRGQ6jazWbAXWIyMWUtjF1VV7+MchN0NmovjYFEQPnZz+nFWJERYjm Tk8HQ18bkYCkTu67gXQ+8aNMBP/TizejsrpzsQMKaw3TPS++TpGqVhQClyoYng0tM2Pb l64sMdf2eUhFKTSCV0la1slhKGj8w9bIl2/doSR1/mT4sl3OQPeD1hqrcIRa+X3AAxqt WX/g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1707785343; x=1708390143; h=mime-version:user-agent:content-transfer-encoding:autocrypt :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=/dwE/gJs3UjhLkiVxd8ovvyGICgHNTOI+7wm4P8nOQE=; b=qwiyNzNUzB7L7AET6Y0MR2cAvfCRJONxfUPymV49r9nufCrKjozsl1CF41kpB7dw63 mP62NUbdx6o23QerxRF9xuVGzUYQDxXHMrSYXp64bs0hWTXShbtFu276KCzI8/YvYLf4 6yisuinNjU0YUm8uxJINz5RN3AO7eYgfzExZrbYAb/xw4K7bWLXHqOpkrTmgsNnyafxB vaVDy11sL7YzzQ9AfbsGiw/p4YxTrv1wxXkv++UxQcYjv/vPGXiSKsVuxV3653IpdArY fLBp/d2v5nmgqarj26+xhYObliUfJZ54+eYnPCaeS63Ao7ICNYHVu9cxb/HKnUXkpXhn LwIw== X-Forwarded-Encrypted: i=1; AJvYcCVlrjBAzm/alxiv/DUwFR99pXvjC3Y7kC3cdYFkLNT1wC5ElFTI9WfZ/Xu5/nu65gi+m6EUkAEd/twNtTTdEdONcJ8= X-Gm-Message-State: AOJu0YyKfRUxahCf/cjEvnNKBFmDPZOcPr9LYdCJKDadMqws/b4VKe/k e81ovW8RmbvvNy7tcVJdjUqLr1MIPBvNwmf9hV8uJ3W2P9TiwVgy X-Google-Smtp-Source: AGHT+IHIYyHIvasJPYh6N03Sm0e3bNL3POKRUz5X/TG+aZ7P3YoEygEh1A7UXrykLL0Pyj7ztfQTHQ== X-Received: by 2002:a17:906:4c57:b0:a3c:8a77:e67d with SMTP id d23-20020a1709064c5700b00a3c8a77e67dmr3416738ejw.59.1707785343422; Mon, 12 Feb 2024 16:49:03 -0800 (PST) X-Forwarded-Encrypted: i=1; AJvYcCWVEMAUG5ZdA41WmN+K04yTub5KSlMncD3n5y/BosNSomLGmeJorCc/JPjggPJoERPq1XsbF/iRV11XMdBfJwApx+ZzU/jsaqz/RkZyPJGA2n++LEOpcjMKoedEjBcAMma/PW3dKe05PwrZlMoiPbEifDGdhJHbnrLVB7Vrj657N/ZkIA1jGNcxYWZsGRCMqorOqHIDrT66IwGK5fuVBukWqbdMpz82sIAIaaJ8TcVYzyG4Ceq/YKClkOu7bbbxpHa4g+t+pcVI65rYsEBLehZL8yt3zR+nKYb+OjEyBV/9a9byxWogammXplD3HEKixlXqWnUZdOyQm5sF+A60ea9DOg5aZkikufHewV6gjxC74fnQ4d9iNMAjUQ== Received: from [192.168.1.94] (host-176-36-0-241.b024.la.net.ua. [176.36.0.241]) by smtp.gmail.com with ESMTPSA id gz3-20020a170906f2c300b00a3793959b4asm715477ejb.134.2024.02.12.16.49.02 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 12 Feb 2024 16:49:03 -0800 (PST) Message-ID: Subject: Re: [PATCH v2 bpf-next 14/20] libbpf: Recognize __arena global varaibles. From: Eduard Zingerman To: Alexei Starovoitov Cc: bpf , Daniel Borkmann , Andrii Nakryiko , Kumar Kartikeya Dwivedi , Tejun Heo , Barret Rhoden , Johannes Weiner , Lorenzo Stoakes , Andrew Morton , Uladzislau Rezki , Christoph Hellwig , linux-mm , Kernel Team Date: Tue, 13 Feb 2024 02:49:01 +0200 In-Reply-To: References: <20240209040608.98927-1-alexei.starovoitov@gmail.com> <20240209040608.98927-15-alexei.starovoitov@gmail.com> Autocrypt: addr=eddyz87@gmail.com; prefer-encrypt=mutual; keydata=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 A+T7mluw nYzhLWGcczc6J71q1Dje0l5vIPaSFOgwmWD4DA+WvuxM/shH4rtWeodbv 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 IYKvsh7s t1iq+gsfnXbPz5AnS598ScZI1oP7OrPSFJkt/z4acEbOQDQs8aUqrd46PV jsdqGvKnXZxzylux29UTNby4jTlz9pNJM+wPrDRmGfchLDUmf6CffaUYCbu4FiId+9+dcTCDvxbABRy1C3OJ8QY7cxfJ+pEZW18fRJ0XCl/fiV/ecAOfB3HsqgTzAn555h0rkFgay0hAvMU/mAW/CFNSIxV397zm749ZNLA0L2dMy1AKuOqH+/B+/ImBfJMDjmdyJQ8WU/OFRuGLdqOd2oZrA1iuPIa+yUYyZkaZfz/emQwpIL1+Q4p1R/OplA4yc301AqruXXUcVDbEB+joHW3hy5FwK5t5OwTKatrSJBkydSF9zdXy98fYzGniRyRA65P0Ix/8J3BYB4edY2/w0Ip/mdYsYQljBY0A== Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.50.3 MIME-Version: 1.0 X-Rspamd-Queue-Id: F2DC7A0012 X-Rspam-User: X-Stat-Signature: r6tdqz98bsm1f3hs8chxsgokwe3bhuca X-Rspamd-Server: rspam01 X-HE-Tag: 1707785344-740926 X-HE-Meta: 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 uwAp5OI1 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Mon, 2024-02-12 at 16:44 -0800, Alexei Starovoitov wrote: > > I hit a strange bug when playing with patch. Consider a simple example = [0]. > > When the following BPF global variable: > >=20 > > int __arena * __arena bar; > >=20 > > - is commented -- the test passes; > > - is uncommented -- in the test fails because global variable 'shared' = is NULL. >=20 > Right. That's expected, because __uint(max_entries, 1); > The test creates an area on 1 page and it's consumed > by int __arena * __arena bar; variable. > Of course, one variable doesn't take the whole page. > There could have been many arena global vars. > But that page is not available anymore to bpf_arena_alloc_pages, > so it returns NULL. My bad, thank you for explaining.