From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-il1-f206.google.com (mail-il1-f206.google.com [209.85.166.206]) (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 37ECD8F6F for ; Fri, 26 Sep 2025 06:45:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.166.206 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758869131; cv=none; b=guhYO86/SLuQBpWvQgNFCFdcGSg4lzYU5P2QXUxJZKFs1UkQRyHmZJ3GY1544EnRRqj0GEkfd/DcKyrxj/MUbaQCk1xwSGyqhBpJ0grLGU0spj1lC+T3z4+m2Z2oszSal0eTi7i7vU0slc4gqYgNt3vkiKUJLx5RJdSekxUyHa4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758869131; c=relaxed/simple; bh=gecowTKj8gdi5IDxs66slsUPgLRG9Dhxu+cope5L4zw=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=seDotn6uGercNgHYrjf21OddSF5twXlsfH9ldFBfa40Wf4MB+dZpeMWBWp+wMU8lILEl1BjwIFGgoF7hjyXj/x/MLnO0/xh5CzS+ihk4CtsfOoaVfUQPB48uTuyhBwRHQcD+u73jJNrmW/ze7j2arYJcAFKh70Lj27jnUtXCCq0= 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=209.85.166.206 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-il1-f206.google.com with SMTP id e9e14a558f8ab-42571c700d2so41502575ab.1 for ; Thu, 25 Sep 2025 23:45:29 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1758869129; x=1759473929; h=to:from:subject:message-id:date:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=1veCcU3mH9oLnhdNlf6mJUGV7a4TAFPi+gLi5uVhv0M=; b=MCrPOBFta2BPO4bLlXxhZFYDDkWOWVt4gOh/J/X13mBBrh7yY4xSzgLP0ALx9CaSJY X7ADs3JXbGZCIejhCUd571hfqqGFkMROLrMQUSrTUOHh0qzqrJBNhm067xydJu9xjniK LjK/mBD3PP6q4G5OueAuYYlCPPIiLdSnwkSgS2msdn2UPyXujjRT0mghNGAn2h/1JTXD revcjLghq0iJB+1QOTVt/41TsuhdrMKtN0Y0E1ZvYqlPLz/AD+dal8zW0BjlppwOizCp qSti91B1dUlEjMiT3rhhqLrDcyfLR/csz1G923/gpH7GT62kvVAjtLpLB3wEUGaNF2Tc lG5A== X-Forwarded-Encrypted: i=1; AJvYcCVnZ5kujuZaaMV7WNuT95qqq647JLJHOrKVSqsehdYn2OtU2uWZxXnVhtIJvf8XkVDkX4y5YuvB0HCAj/8=@vger.kernel.org X-Gm-Message-State: AOJu0YzK9PwR1bniay+dq35vg+NNh1l76jtwfXgPK6tZByUo4gbrS2fy X5rETcZGQLQRklPfRwebOrYixTWo0iaeCKvkunBIeO6SnEjpZC93lOQFGmV1LYH/4urVANzoA5x A55ZXrr5l986NO+Bc/XGN7a+ikLCc+Bim8/VSm257AGAu9ajB21FUZUwjQtA= X-Google-Smtp-Source: AGHT+IGt9fmY+fMre+iBYy4LP8OBoS/OyInBYpNKNG9zH0SZ97oV98zut4bI7DGrK0yZbXbA8dni2nbYBirwgoVX3tXsVCJw/Ahb Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6e02:490d:b0:418:84eb:ea20 with SMTP id e9e14a558f8ab-4259562f43bmr90064995ab.15.1758869129365; Thu, 25 Sep 2025 23:45:29 -0700 (PDT) Date: Thu, 25 Sep 2025 23:45:29 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <68d63689.050a0220.25d7ab.00d9.GAE@google.com> Subject: [syzbot] [mm?] KCSAN: data-race in try_to_compact_pages / try_to_compact_pages From: syzbot To: akpm@linux-foundation.org, hannes@cmpxchg.org, jackmanb@google.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, mhocko@suse.com, surenb@google.com, syzkaller-bugs@googlegroups.com, vbabka@suse.cz, ziy@nvidia.com Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: cec1e6e5d1ab Merge tag 'sched_ext-for-6.17-rc7-fixes' of g.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=12448f12580000 kernel config: https://syzkaller.appspot.com/x/.config?x=6e0c213d0735f5dd dashboard link: https://syzkaller.appspot.com/bug?extid=20dd68d4ba19e8242c26 compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/10b7c8fdfdec/disk-cec1e6e5.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/cbecc36962db/vmlinux-cec1e6e5.xz kernel image: https://storage.googleapis.com/syzbot-assets/214f107d0a3e/bzImage-cec1e6e5.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+20dd68d4ba19e8242c26@syzkaller.appspotmail.com ================================================================== BUG: KCSAN: data-race in try_to_compact_pages / try_to_compact_pages read-write to 0xffff88823fffacf0 of 4 bytes by task 6757 on cpu 1: compaction_deferred mm/compaction.c:149 [inline] try_to_compact_pages+0x1be/0x940 mm/compaction.c:2838 __alloc_pages_direct_compact+0x65/0x1d0 mm/page_alloc.c:4066 __alloc_pages_slowpath+0x360/0x5f0 mm/page_alloc.c:4787 __alloc_frozen_pages_noprof+0x270/0x360 mm/page_alloc.c:5161 alloc_pages_mpol+0xb3/0x250 mm/mempolicy.c:2416 alloc_frozen_pages_noprof+0x90/0x110 mm/mempolicy.c:2487 ___kmalloc_large_node+0x52/0x100 mm/slub.c:4317 __kmalloc_large_node_noprof+0x16/0xa0 mm/slub.c:4348 __do_kmalloc_node mm/slub.c:4364 [inline] __kmalloc_noprof+0x2ab/0x3e0 mm/slub.c:4388 kmalloc_noprof include/linux/slab.h:909 [inline] kmalloc_array_noprof include/linux/slab.h:948 [inline] io_vec_realloc io_uring/rsrc.c:1327 [inline] io_import_reg_vec+0x645/0xe80 io_uring/rsrc.c:1520 io_sendmsg_zc+0x91/0x550 io_uring/net.c:1545 __io_issue_sqe+0xfb/0x2e0 io_uring/io_uring.c:1771 io_issue_sqe+0x53/0x970 io_uring/io_uring.c:1794 io_queue_sqe io_uring/io_uring.c:2023 [inline] io_submit_sqe io_uring/io_uring.c:2283 [inline] io_submit_sqes+0x675/0x1060 io_uring/io_uring.c:2396 __do_sys_io_uring_enter io_uring/io_uring.c:3463 [inline] __se_sys_io_uring_enter+0x1c1/0x1b70 io_uring/io_uring.c:3397 __x64_sys_io_uring_enter+0x78/0x90 io_uring/io_uring.c:3397 x64_sys_call+0x2de1/0x2ff0 arch/x86/include/generated/asm/syscalls_64.h:427 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f write to 0xffff88823fffacf0 of 4 bytes by task 6696 on cpu 0: compaction_deferred mm/compaction.c:150 [inline] try_to_compact_pages+0x207/0x940 mm/compaction.c:2838 __alloc_pages_direct_compact+0x65/0x1d0 mm/page_alloc.c:4066 __alloc_pages_slowpath+0x360/0x5f0 mm/page_alloc.c:4787 __alloc_frozen_pages_noprof+0x270/0x360 mm/page_alloc.c:5161 alloc_pages_mpol+0xb3/0x250 mm/mempolicy.c:2416 alloc_frozen_pages_noprof+0x90/0x110 mm/mempolicy.c:2487 ___kmalloc_large_node+0x52/0x100 mm/slub.c:4317 __kmalloc_large_node_noprof+0x16/0xa0 mm/slub.c:4348 __do_kmalloc_node mm/slub.c:4364 [inline] __kmalloc_noprof+0x2ab/0x3e0 mm/slub.c:4388 kmalloc_noprof include/linux/slab.h:909 [inline] kmalloc_array_noprof include/linux/slab.h:948 [inline] io_vec_realloc io_uring/rsrc.c:1327 [inline] io_import_reg_vec+0x645/0xe80 io_uring/rsrc.c:1520 io_sendmsg_zc+0x91/0x550 io_uring/net.c:1545 __io_issue_sqe+0xfb/0x2e0 io_uring/io_uring.c:1771 io_issue_sqe+0x53/0x970 io_uring/io_uring.c:1794 io_queue_sqe io_uring/io_uring.c:2023 [inline] io_submit_sqe io_uring/io_uring.c:2283 [inline] io_submit_sqes+0x675/0x1060 io_uring/io_uring.c:2396 __do_sys_io_uring_enter io_uring/io_uring.c:3463 [inline] __se_sys_io_uring_enter+0x1c1/0x1b70 io_uring/io_uring.c:3397 __x64_sys_io_uring_enter+0x78/0x90 io_uring/io_uring.c:3397 x64_sys_call+0x2de1/0x2ff0 arch/x86/include/generated/asm/syscalls_64.h:427 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f value changed: 0x00000005 -> 0x00000004 Reported by Kernel Concurrency Sanitizer on: CPU: 0 UID: 0 PID: 6696 Comm: syz.2.1234 Not tainted syzkaller #0 PREEMPT(voluntary) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 ================================================================== --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@googlegroups.com. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. If the report is already addressed, let syzbot know by replying with: #syz fix: exact-commit-title If you want to overwrite report's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the report is a duplicate of another one, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup