From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-il1-f205.google.com (mail-il1-f205.google.com [209.85.166.205]) (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 401412BEFE3 for ; Fri, 19 Sep 2025 14:20:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.166.205 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758291638; cv=none; b=uRJeWeznFRjbqFGCy33BwoITf95dJdm3WNIzZaQh9T87C1z/yNCFvk2KGJtZx9AfD62gWqbnyPBuf3CidGS5z6G9X4Lc5h5xuUliX71IP6W6o0N8UL/htTizvkpBZoBnrHGBnCo4rr1WYy2Nju5sGXLxHAbfAkd5OaZN5VCNzX0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758291638; c=relaxed/simple; bh=yyHzu7LU6UfA/2ViB685lY1SCHRlisjwkZH35/UJBDs=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=O9dONVlhSLKKr5wjK2MVave7wORqrMk+M8zmUH0lRCkc9W2N10DbtYBpKCrh0I5oebn4GWJsSHC9BgZshFshLJnwZz+INk2jH8RCBVPlAlRWzX10HPYoJL3uOu/1+7o5KxpdARfuUyu1i7iL28eNg3Q7TMYBiXb9a/BvEJQyr6o= 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=209.85.166.205 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-f205.google.com with SMTP id e9e14a558f8ab-4241c41110eso46596665ab.1 for ; Fri, 19 Sep 2025 07:20:36 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1758291636; x=1758896436; h=to:from:subject:message-id:date:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=Z4GbzlWauoCPLt/KdIunfCOqOx+l+jd7WNBw7s5fAcc=; b=hj11l9+u/XZ0SDTQmGXjv/yg6dwjFPqMD5wmgzXCWRkqnYmFPQg3BMxQyT5duiYkw3 TwZ28cy62xaBHURIglRl/MaMYijlhTyMpexTqGIN6sd889ou1MHbVcGofBQk9QUtLwLd /UFHLBno/TuAYLvAXOI8k8DdJ0rFLllwF+7rPkFI5//Pi4AvDY9BlGNjvb2gg9VAZPuO h5dU1d+lOYI2jvdMPg0c7JhKXQCdP0CK42aDQ0u0NhRjPA/Rvgzhd98TD2gawkFQ52r1 D6ojkGRNzjKqW39uVkC6h4LEFdXjKMctVneYJ0GpOEYEnMjxvPDk1f0g6a9B1Gje/b2r 2s0g== X-Forwarded-Encrypted: i=1; AJvYcCVJPsVD4R9ll7MJgUxpKx7ArO0j8WtZJBreEI9/3jeYFHHcNPCq6kN0Kh8dzbFqOVAWvCgiz/E=@lists.linux.dev X-Gm-Message-State: AOJu0YwTAmBzgsDmTi1K7OrfGXzjdOUYdG9nWUbLv5xJgOQ+u9RfLyNe aYIy/2TfrGCcmS0gX4TJqsuqCQmDFrqWyx8lVZw64OE7bDguQ3RJV4yUtZ7HWVgQFgUEBc5Gydv QTHLnRbSpGUaPks8ToEpBzvCrNkyWia5bXoASV2fLYKPJkHZHJSUNhl9rFVs= X-Google-Smtp-Source: AGHT+IHptP33yYtPA/hPB7VlA/qo5/m+4BnaVJm9r2lCaoHLdmJGLCxFZ8S8jen0SfTFLsgSyaGtWr7jx6EIxmUqo3jsnUIzS0p6 Precedence: bulk X-Mailing-List: kvmarm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6e02:2185:b0:40d:e50a:35b0 with SMTP id e9e14a558f8ab-4248199ec8fmr53120515ab.32.1758291632840; Fri, 19 Sep 2025 07:20:32 -0700 (PDT) Date: Fri, 19 Sep 2025 07:20:32 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <68cd66b0.050a0220.139b6.000f.GAE@google.com> Subject: [syzbot] [kvmarm?] kernel BUG in kvm_s2_put_page From: syzbot To: catalin.marinas@arm.com, joey.gouly@arm.com, kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, maz@kernel.org, oliver.upton@linux.dev, suzuki.poulose@arm.com, syzkaller-bugs@googlegroups.com, will@kernel.org, yuzenghui@huawei.com Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: 62e68218ab58 Merge branch kvm-arm64/nv-debug into kvmarm-m.. git tree: git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm.git next console output: https://syzkaller.appspot.com/x/log.txt?x=1551cf62580000 kernel config: https://syzkaller.appspot.com/x/.config?x=1b1bafe30fc85201 dashboard link: https://syzkaller.appspot.com/bug?extid=c41f3ddb8299a30a98b5 compiler: Debian clang version 20.1.8 (++20250708123704+0de59a293f7a-1~exp1~20250708003721.134), Debian LLD 20.1.8 userspace arch: arm64 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/fa3fbcfdac58/non_bootable_disk-62e68218.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/99c4e665c20d/vmlinux-62e68218.xz kernel image: https://storage.googleapis.com/syzbot-assets/4204d63db4b5/Image-62e68218.gz.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+c41f3ddb8299a30a98b5@syzkaller.appspotmail.com raw: 01ffea8000000000 ffffc1ffc0807c48 ffffc1ffc080a888 0000000000000000 raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: VM_BUG_ON_PAGE(page_ref_count(page) == 0) ------------[ cut here ]------------ kernel BUG at ./include/linux/mm.h:1036! Internal error: Oops - BUG: 00000000f2000800 [#1] SMP Modules linked in: CPU: 0 UID: 0 PID: 4079 Comm: syz.1.200 Not tainted syzkaller #0 PREEMPT Hardware name: linux,dummy-virt (DT) pstate: 60402009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : put_page_testzero include/linux/mm.h:1036 [inline] pc : folio_put_testzero include/linux/mm.h:1042 [inline] pc : folio_put include/linux/mm.h:1359 [inline] pc : put_page include/linux/mm.h:1429 [inline] pc : kvm_s2_put_page+0x374/0x3a0 arch/arm64/kvm/mmu.c:264 lr : put_page_testzero include/linux/mm.h:1036 [inline] lr : folio_put_testzero include/linux/mm.h:1042 [inline] lr : folio_put include/linux/mm.h:1359 [inline] lr : put_page include/linux/mm.h:1429 [inline] lr : kvm_s2_put_page+0x374/0x3a0 arch/arm64/kvm/mmu.c:264 sp : ffff80008edd7570 x29: ffff80008edd7570 x28: a4f00000202a2000 x27: a4f00000202a2000 x26: 00000000000000ff x25: ffff80008734e000 x24: ffffc1ffc0000000 x23: ffffc1ffc0806908 x22: 0000000000000000 x21: ffffc1ffc0806934 x20: 0000000000000000 x19: ffffc1ffc0806900 x18: 000000004afc0585 x17: 0000000004687c8c x16: 000000004af050f5 x15: 0000000089957307 x14: ffffffffffffffff x13: fff0000012103b08 x12: 0000000000000001 x11: 0000000000080000 x10: 0000000000031ed7 x9 : c866620449182600 x8 : c866620449182600 x7 : ffff80008039fbc8 x6 : 0000000000000000 x5 : 0000000000000001 x4 : 0000000000000001 x3 : ffff800080390dd0 x2 : 0000000000000002 x1 : 0000000100000000 x0 : 000000000000003e Call trace: put_page_testzero include/linux/mm.h:1036 [inline] (P) folio_put_testzero include/linux/mm.h:1042 [inline] (P) folio_put include/linux/mm.h:1359 [inline] (P) put_page include/linux/mm.h:1429 [inline] (P) kvm_s2_put_page+0x374/0x3a0 arch/arm64/kvm/mmu.c:264 (P) stage2_free_walker+0x1b0/0x264 arch/arm64/kvm/hyp/pgtable.c:1549 kvm_pgtable_visitor_cb arch/arm64/kvm/hyp/pgtable.c:130 [inline] __kvm_pgtable_visit arch/arm64/kvm/hyp/pgtable.c:212 [inline] __kvm_pgtable_walk+0x7d8/0xa68 arch/arm64/kvm/hyp/pgtable.c:237 _kvm_pgtable_walk arch/arm64/kvm/hyp/pgtable.c:260 [inline] kvm_pgtable_walk+0x294/0x468 arch/arm64/kvm/hyp/pgtable.c:283 kvm_pgtable_stage2_destroy_range+0x60/0xb4 arch/arm64/kvm/hyp/pgtable.c:1563 stage2_destroy_range arch/arm64/kvm/mmu.c:924 [inline] kvm_stage2_destroy arch/arm64/kvm/mmu.c:935 [inline] kvm_free_stage2_pgd+0x198/0x28c arch/arm64/kvm/mmu.c:1112 kvm_uninit_stage2_mmu+0x20/0x38 arch/arm64/kvm/mmu.c:1023 kvm_arch_flush_shadow_all+0x1a8/0x1e0 arch/arm64/kvm/nested.c:1113 kvm_flush_shadow_all virt/kvm/kvm_main.c:343 [inline] kvm_mmu_notifier_release+0x48/0xa8 virt/kvm/kvm_main.c:884 mmu_notifier_unregister+0x128/0x42c mm/mmu_notifier.c:815 kvm_destroy_vm virt/kvm/kvm_main.c:1295 [inline] kvm_put_kvm+0x6a0/0xfa8 virt/kvm/kvm_main.c:1353 kvm_vcpu_release+0x70/0x9c virt/kvm/kvm_main.c:4100 __fput+0x4ac/0x980 fs/file_table.c:468 ____fput+0x20/0x58 fs/file_table.c:496 task_work_run+0x1bc/0x254 kernel/task_work.c:227 get_signal+0x13ec/0x1554 kernel/signal.c:2807 do_signal+0x23c/0x4dd0 arch/arm64/kernel/signal.c:1618 do_notify_resume+0xb0/0x270 arch/arm64/kernel/entry-common.c:152 exit_to_user_mode_prepare arch/arm64/kernel/entry-common.c:173 [inline] exit_to_user_mode arch/arm64/kernel/entry-common.c:182 [inline] el0_svc+0xb8/0x164 arch/arm64/kernel/entry-common.c:880 el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:898 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596 Code: f00375a1 9112fc21 aa1303e0 97f9c9f2 (d4210000) ---[ end trace 0000000000000000 ]--- --- 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