From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-io1-f69.google.com (mail-io1-f69.google.com [209.85.166.69]) (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 ADE581B1405 for ; Thu, 29 Aug 2024 16:53:20 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.166.69 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724950402; cv=none; b=F/pu55hZDFhdwRkGiWhLiZfZxFAnoMD2fhwFB0IkPhtlquT/9aQvyTiqy0Ryxa5rUJOUN3lgUjqFVGPKphaNhWjU3j3TrgFrYWzn5EaW95Kx6w1sDMiHlGO0F5s1hFqPTDkYmV3Hr9uBxNszB93lMiQCmZIEBw2Tqe+gmVj0UWI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724950402; c=relaxed/simple; bh=0oKOG1inFNenjW3THv8ilJlWnxV5ZD2iXnnNpWukEBk=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=vEuSRfxLrt2GdBYYtb5WrmMipkePCkvqOQy5TDRgzXAw6gFxG/yNPkv/y7sNZp9U+zyxpLYJtUIXI2j7DNiUQJjx0XYwwVT7C9TuyACxqFwsxFe70TIE0ntLuEqk91DyGHjkINqPDVddOyt3iXPmIJBx2+jjJSFwDRM9rOW/k1I= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com; arc=none smtp.client-ip=209.85.166.69 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com Received: by mail-io1-f69.google.com with SMTP id ca18e2360f4ac-824c925d120so92613439f.3 for ; Thu, 29 Aug 2024 09:53:20 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1724950400; x=1725555200; h=to:from:subject:message-id:date:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=/BvFh4ndpSTJeKsROL2z+JLa5B9vKHfCjmHGQdFDneA=; b=VCqt9Exr5VHUeIsXZlfIYV1EQ9brCP1/KD5awWXGJRTsEm7LDHC7qxU36kASuYg5Rm lUVgOzsGHloVS21G41iH6+1G9PC3bPwAV0SPdTNCRuB3L7Hsvw5sTyaVGOxEagXCFm3Y TjgO+NjjJ3s/o/Gfq3UVMsPKUWVS02roCv5i3Q+t/lxPE7GKQveiDsIJRoPRH+I+JmR6 rNPHH6nqWlgoZ7U9x1oJmmOBuVgNx1aJYSaRIvBE0QXkrm9ZRLnsEPoRqQTLEjhIzzh6 Hpn4Uvqbo13PdPK5O5tfc+v1FI0i4jbDEBATrj/XZMaCipxeNC4FAmCfkpSoTdlWHS6W VJgg== X-Forwarded-Encrypted: i=1; AJvYcCU630dDHbiZT5KcbK0azOetXb3iwE47Yxj/c4BXGvqx5pN8xHU7/Ziw+n+qSxrK/LHL69oam+NiCUn3lSU=@vger.kernel.org X-Gm-Message-State: AOJu0YyR2bD4WrvBdUXCQV3wg1+vzTX20sEqtBkWcIQ3SCpmY3gwXOSy qK4Va4zCHeV1VV+cbAh8edU1axlPTDM6yIwPrU78x48r9wUmtj2xCe7KrxKeS4Y0RayKbPB2qfn y+YqOGbZRr+bx2Tebvt4/BqhpZO/tZ23SJFQsWDi+A22LUWxeeFdj2RY= X-Google-Smtp-Source: AGHT+IHF04MiPKHvS0qCkvfitYymrc11DsbiSg2cSsiR8bXwNGg5PRs4wUJNvgMlI+cUgd5L7sdOrnNc0/WmenJieWjiwwzV/vIE Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6638:37a8:b0:4be:d44b:de24 with SMTP id 8926c6da1cb9f-4cecff9b544mr112344173.2.1724950399706; Thu, 29 Aug 2024 09:53:19 -0700 (PDT) Date: Thu, 29 Aug 2024 09:53:19 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <000000000000d47d440620d54f15@google.com> Subject: [syzbot] [kernel?] KCSAN: data-race in pcpu_alloc_noprof / pcpu_balance_workfn (2) From: syzbot To: bp@alien8.de, dave.hansen@linux.intel.com, hpa@zytor.com, linux-kernel@vger.kernel.org, mingo@redhat.com, syzkaller-bugs@googlegroups.com, tglx@linutronix.de, x86@kernel.org Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: d5d547aa7b51 Merge tag 'random-6.11-rc6-for-linus' of git:.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=164c067b980000 kernel config: https://syzkaller.appspot.com/x/.config?x=6fafac02e339cc84 dashboard link: https://syzkaller.appspot.com/bug?extid=6d392a44667baa45bb5a compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/e636aa58c364/disk-d5d547aa.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/f5ecd0d96afa/vmlinux-d5d547aa.xz kernel image: https://storage.googleapis.com/syzbot-assets/fe7d474f148f/bzImage-d5d547aa.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+6d392a44667baa45bb5a@syzkaller.appspotmail.com ================================================================== BUG: KCSAN: data-race in pcpu_alloc_noprof / pcpu_balance_workfn read-write to 0xffffffff88bb27ac of 4 bytes by task 3354 on cpu 0: pcpu_update_empty_pages mm/percpu.c:602 [inline] pcpu_chunk_populated mm/percpu.c:1531 [inline] pcpu_balance_populated mm/percpu.c:2062 [inline] pcpu_balance_workfn+0x94e/0xa60 mm/percpu.c:2212 process_one_work kernel/workqueue.c:3231 [inline] process_scheduled_works+0x483/0x9a0 kernel/workqueue.c:3312 worker_thread+0x526/0x6e0 kernel/workqueue.c:3389 kthread+0x1d1/0x210 kernel/kthread.c:389 ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 read to 0xffffffff88bb27ac of 4 bytes by task 6821 on cpu 1: pcpu_alloc_noprof+0x9a7/0x10c0 mm/percpu.c:1894 bpf_map_alloc_percpu+0xad/0x210 kernel/bpf/syscall.c:466 prealloc_init+0x19f/0x470 kernel/bpf/hashtab.c:341 htab_map_alloc+0x630/0x8e0 kernel/bpf/hashtab.c:576 map_create+0x83c/0xb90 kernel/bpf/syscall.c:1333 __sys_bpf+0x667/0x7a0 kernel/bpf/syscall.c:5692 __do_sys_bpf kernel/bpf/syscall.c:5817 [inline] __se_sys_bpf kernel/bpf/syscall.c:5815 [inline] __x64_sys_bpf+0x43/0x50 kernel/bpf/syscall.c:5815 x64_sys_call+0x2625/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:322 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f value changed: 0x00000001 -> 0x00000004 Reported by Kernel Concurrency Sanitizer on: CPU: 1 UID: 0 PID: 6821 Comm: syz.4.1651 Not tainted 6.11.0-rc5-syzkaller-00081-gd5d547aa7b51 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 ================================================================== --- This report is generated by a bot. 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