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]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 790ADCCFA13 for ; Mon, 10 Nov 2025 15:19:21 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 987058E0027; Mon, 10 Nov 2025 10:19:20 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 9364E8E000B; Mon, 10 Nov 2025 10:19:20 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 825258E0027; Mon, 10 Nov 2025 10:19:20 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) by kanga.kvack.org (Postfix) with ESMTP id 6E3748E000B for ; Mon, 10 Nov 2025 10:19:20 -0500 (EST) Received: from smtpin01.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay08.hostedemail.com (Postfix) with ESMTP id 22ABD14016F for ; Mon, 10 Nov 2025 15:19:20 +0000 (UTC) X-FDA: 84095056080.01.60750BE Received: from mail-il1-f200.google.com (mail-il1-f200.google.com [209.85.166.200]) by imf06.hostedemail.com (Postfix) with ESMTP id 7388E180017 for ; Mon, 10 Nov 2025 15:19:18 +0000 (UTC) Authentication-Results: imf06.hostedemail.com; dkim=none; spf=pass (imf06.hostedemail.com: domain of 3dQISaQkbABIAGH2s33w9s770v.y66y3wCAw9u65Bw5B.u64@M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com designates 209.85.166.200 as permitted sender) smtp.mailfrom=3dQISaQkbABIAGH2s33w9s770v.y66y3wCAw9u65Bw5B.u64@M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com; dmarc=fail reason="SPF not aligned (relaxed), No valid DKIM" header.from=appspotmail.com (policy=none) ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1762787958; 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: in-reply-to:in-reply-to:references; bh=fZ2NWlZ546cks4M6j4DNqCc2vYjUuH0vrlSlhM9Y2K8=; b=TCqWDn0vnFqbwPyxMjVhb+POSbEmtGSMgNa+sGz6l78fwKkWeOV7kRCGGVFhB8etgheA/Z +TrVUAH2gumbzh546VWCjYRIjVYj/EMCZ9vJ8LglsP+hKqbaDFoyK3gFAozoc/IgOtcVX8 5IXDHcEHAygC6xz6g+M+HLAA3H1888c= ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1762787958; a=rsa-sha256; cv=none; b=Hp2Thmdxw7bYRGaxTMyC/y6xOKkXuJw0LLWEilDVQ5Nz3j4Fj6xJwnLwDRSMZy8N3ofiYN ZOVxtCRSztaCwYRCM5DHJug5uo/qPRERQmZ/TK0t5OCNJZG60OOhPPGZwJVeM118vlvEuB tjFEwYDIybnwmAgZZ8LpOfLyYv0VWi8= ARC-Authentication-Results: i=1; imf06.hostedemail.com; dkim=none; spf=pass (imf06.hostedemail.com: domain of 3dQISaQkbABIAGH2s33w9s770v.y66y3wCAw9u65Bw5B.u64@M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com designates 209.85.166.200 as permitted sender) smtp.mailfrom=3dQISaQkbABIAGH2s33w9s770v.y66y3wCAw9u65Bw5B.u64@M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com; dmarc=fail reason="SPF not aligned (relaxed), No valid DKIM" header.from=appspotmail.com (policy=none) Received: by mail-il1-f200.google.com with SMTP id e9e14a558f8ab-432fb58f876so111589855ab.1 for ; Mon, 10 Nov 2025 07:19:18 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1762787957; x=1763392757; h=cc:to:from:subject:message-id:in-reply-to:date:mime-version :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=fZ2NWlZ546cks4M6j4DNqCc2vYjUuH0vrlSlhM9Y2K8=; b=kf2E2VxjE0tRR6eADHO2yqj8vLilbfR0X0ogjv2ohSNGkcdvul4aI0KGGTqM67/P84 orP8hyGfkguRU4Ufg5x+7fouTDbjE/giXD86MxDWRzhggH/isCBmcihynP3pE5hVizWY SzzegwJr9DzQ0G189KSMXWbq3jUtjL81hPduV8ImV5zWa9vCMm/RYgi4yfa+1h+0F1lW SkFvoBPPSLRFQDT8EFYKOoBCQ893Dxghq3QwWL8mYDOYzSiFyW+ZILlJXDurIcFXdiFX 0kiUuzKQnrUdOQJ4SJT/D3HK/9SJD+EQt0wLbYS9sxI7elB6zqNSYRWkx06ASTPhc67Z yLPw== X-Forwarded-Encrypted: i=1; AJvYcCWGzdts3FLkssns00l9MURy49/oPt2iHU8tPQTrZPMO4ET7h0tKKn2zgwlNrpYcN3SKZj+o49G0gA==@kvack.org X-Gm-Message-State: AOJu0YwKAgnQcqD2mJZFbG2wNBtcY2oHeudpqz83gTyeVT0sR0kMBWsX 53qAi6Q7fJw1CNCzsdiKtP8QUB3hd+jzUQs6pyWRumxVuodxPiTKwi7twkfxQeLYz4jNz96IPm9 k5yZ29ZryZ7a1+MFgWl5kTCv+qdjhTx66tuoHJ+aOUdgN0J+MakDLaRLjvbs= X-Google-Smtp-Source: AGHT+IFT43QlM8pcln8U+Eww+O0zzAExm6XXgPQBWfT6KRG7VIkvfXjO0jztElePth8ZM3wp+BZTjgkncLB2kVRNvkTts8Hag2iy MIME-Version: 1.0 X-Received: by 2002:a92:cccd:0:b0:433:7310:f5bf with SMTP id e9e14a558f8ab-4337310f94amr69754165ab.22.1762787957532; Mon, 10 Nov 2025 07:19:17 -0800 (PST) Date: Mon, 10 Nov 2025 07:19:17 -0800 In-Reply-To: <20251110111553.88384-1-lance.yang@linux.dev> X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <69120275.a70a0220.22f260.00f7.GAE@google.com> Subject: [syzbot ci] Re: mm/hugetlb: fix possible deadlocks in hugetlb VMA unmap paths From: syzbot ci To: akpm@linux-foundation.org, david@redhat.com, lance.yang@linux.dev, linux-kernel@vger.kernel.org, linux-mm@kvack.org, muchun.song@linux.dev, osalvador@suse.de, syzbot@lists.linux.dev, syzbot@syzkaller.appspotmail.com, syzkaller-bugs@googlegroups.com Cc: syzbot@lists.linux.dev, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 7388E180017 X-Stat-Signature: c8xdiaxay3n4uexg3qfn1ou4dkroeiqw X-Rspam-User: X-HE-Tag: 1762787958-675701 X-HE-Meta: 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 B7/O95aq 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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: syzbot ci has tested the following series [v2] mm/hugetlb: fix possible deadlocks in hugetlb VMA unmap paths https://lore.kernel.org/all/20251110111553.88384-1-lance.yang@linux.dev * [PATCH v2 1/1] mm/hugetlb: fix possible deadlocks in hugetlb VMA unmap paths and found the following issue: possible deadlock in unmap_vmas Full report is available here: https://ci.syzbot.org/series/3106300b-af9f-40dc-985b-33cb937712aa *** possible deadlock in unmap_vmas tree: mm-new URL: https://kernel.googlesource.com/pub/scm/linux/kernel/git/akpm/mm.git base: 02dafa01ec9a00c3758c1c6478d82fe601f5f1ba arch: amd64 compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8 config: https://ci.syzbot.org/builds/089d8dad-bc85-4724-8a79-2ad934becf17/config C repro: https://ci.syzbot.org/findings/3dded3f6-aef2-4f4c-9dba-b23214df5e12/c_repro syz repro: https://ci.syzbot.org/findings/3dded3f6-aef2-4f4c-9dba-b23214df5e12/syz_repro ====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.0.17/5963 is trying to acquire lock: ffff88816cbda8e8 (&resv_map->rw_sema){+.+.}-{4:4}, at: hugetlb_zap_begin include/linux/hugetlb.h:257 [inline] ffff88816cbda8e8 (&resv_map->rw_sema){+.+.}-{4:4}, at: unmap_vmas+0x23d/0x580 mm/memory.c:2098 but task is already holding lock: ffff888172c80418 (&hugetlbfs_i_mmap_rwsem_key){+.+.}-{4:4}, at: i_mmap_lock_write include/linux/fs.h:548 [inline] ffff888172c80418 (&hugetlbfs_i_mmap_rwsem_key){+.+.}-{4:4}, at: __hugetlb_zap_begin+0x2aa/0x3a0 mm/hugetlb.c:5331 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&hugetlbfs_i_mmap_rwsem_key){+.+.}-{4:4}: lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868 down_write+0x96/0x1f0 kernel/locking/rwsem.c:1590 i_mmap_lock_write include/linux/fs.h:548 [inline] hugetlb_change_protection+0x56a/0x18c0 mm/hugetlb.c:6439 change_protection+0x386/0x38c0 mm/mprotect.c:655 mprotect_fixup+0x6fe/0x9c0 mm/mprotect.c:774 do_mprotect_pkey+0x8c5/0xcd0 mm/mprotect.c:930 __do_sys_mprotect mm/mprotect.c:951 [inline] __se_sys_mprotect mm/mprotect.c:948 [inline] __x64_sys_mprotect+0x80/0x90 mm/mprotect.c:948 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 (&resv_map->rw_sema){+.+.}-{4:4}: check_prev_add kernel/locking/lockdep.c:3165 [inline] check_prevs_add kernel/locking/lockdep.c:3284 [inline] validate_chain+0xb9b/0x2140 kernel/locking/lockdep.c:3908 __lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5237 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868 down_write+0x96/0x1f0 kernel/locking/rwsem.c:1590 hugetlb_zap_begin include/linux/hugetlb.h:257 [inline] unmap_vmas+0x23d/0x580 mm/memory.c:2098 exit_mmap+0x23e/0xb30 mm/mmap.c:1277 __mmput+0x118/0x430 kernel/fork.c:1133 exit_mm+0x1da/0x2c0 kernel/exit.c:582 do_exit+0x648/0x2300 kernel/exit.c:954 do_group_exit+0x21c/0x2d0 kernel/exit.c:1107 __do_sys_exit_group kernel/exit.c:1118 [inline] __se_sys_exit_group kernel/exit.c:1116 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1116 x64_sys_call+0x21f7/0x2200 arch/x86/include/generated/asm/syscalls_64.h:232 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&hugetlbfs_i_mmap_rwsem_key); lock(&resv_map->rw_sema); lock(&hugetlbfs_i_mmap_rwsem_key); lock(&resv_map->rw_sema); *** DEADLOCK *** 2 locks held by syz.0.17/5963: #0: ffff88810e0f8ca0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:365 [inline] #0: ffff88810e0f8ca0 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x126/0xb30 mm/mmap.c:1262 #1: ffff888172c80418 (&hugetlbfs_i_mmap_rwsem_key){+.+.}-{4:4}, at: i_mmap_lock_write include/linux/fs.h:548 [inline] #1: ffff888172c80418 (&hugetlbfs_i_mmap_rwsem_key){+.+.}-{4:4}, at: __hugetlb_zap_begin+0x2aa/0x3a0 mm/hugetlb.c:5331 stack backtrace: CPU: 1 UID: 0 PID: 5963 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_circular_bug+0x2ee/0x310 kernel/locking/lockdep.c:2043 check_noncircular+0x134/0x160 kernel/locking/lockdep.c:2175 check_prev_add kernel/locking/lockdep.c:3165 [inline] check_prevs_add kernel/locking/lockdep.c:3284 [inline] validate_chain+0xb9b/0x2140 kernel/locking/lockdep.c:3908 __lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5237 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868 down_write+0x96/0x1f0 kernel/locking/rwsem.c:1590 hugetlb_zap_begin include/linux/hugetlb.h:257 [inline] unmap_vmas+0x23d/0x580 mm/memory.c:2098 exit_mmap+0x23e/0xb30 mm/mmap.c:1277 __mmput+0x118/0x430 kernel/fork.c:1133 exit_mm+0x1da/0x2c0 kernel/exit.c:582 do_exit+0x648/0x2300 kernel/exit.c:954 do_group_exit+0x21c/0x2d0 kernel/exit.c:1107 __do_sys_exit_group kernel/exit.c:1118 [inline] __se_sys_exit_group kernel/exit.c:1116 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1116 x64_sys_call+0x21f7/0x2200 arch/x86/include/generated/asm/syscalls_64.h:232 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f6bb058efc9 Code: Unable to access opcode bytes at 0x7f6bb058ef9f. RSP: 002b:00007ffedbb6b2f8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f6bb058efc9 RDX: 0000000000000064 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000003 R08: 00000002dbb6b3ef R09: 00007f6bb07b1280 R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f6bb07b1280 R14: 0000000000000003 R15: 00007ffedbb6b3b0 *** If these findings have caused you to resend the series or submit a separate fix, please add the following tag to your commit message: Tested-by: syzbot@syzkaller.appspotmail.com --- This report is generated by a bot. It may contain errors. syzbot ci engineers can be reached at syzkaller@googlegroups.com.