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[23.128.96.34]) by mx.google.com with ESMTPS id a10-20020a170902b58a00b001c9c83947d1si2163277pls.645.2023.11.30.17.48.07 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 30 Nov 2023 17:48:11 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.34 as permitted sender) client-ip=23.128.96.34; Authentication-Results: mx.google.com; dkim=pass header.i=@quora.org header.s=google header.b=jZ81U65k; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.34 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: from out1.vger.email (depot.vger.email [IPv6:2620:137:e000::3:0]) by howler.vger.email (Postfix) with ESMTP id C86A8853A0EE; Thu, 30 Nov 2023 17:48:02 -0800 (PST) X-Virus-Status: Clean X-Virus-Scanned: clamav-milter 0.103.11 at howler.vger.email Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1376375AbjLABrn (ORCPT + 99 others); Thu, 30 Nov 2023 20:47:43 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56866 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229448AbjLABrm (ORCPT ); Thu, 30 Nov 2023 20:47:42 -0500 Received: from mail-ed1-x536.google.com (mail-ed1-x536.google.com [IPv6:2a00:1450:4864:20::536]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 37AF210F8 for ; Thu, 30 Nov 2023 17:47:46 -0800 (PST) Received: by mail-ed1-x536.google.com with SMTP id 4fb4d7f45d1cf-54bf9a54fe3so1902274a12.3 for ; Thu, 30 Nov 2023 17:47:46 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=quora.org; s=google; t=1701395264; x=1702000064; darn=vger.kernel.org; h=cc:to:subject:message-id:date:from:mime-version:from:to:cc:subject :date:message-id:reply-to; bh=U3HR5X5vF0aKqgSP9mL/Ey54FJixI2TYNBnr1Kpa3lA=; b=jZ81U65kaOD0/3rQYu2vWPFxrVDVRjHJkc7k+GZbCTmv+KxXL5t4qU8SnjJrtR6+g+ 5k7+v3wQSmT0ZErYDQYJF2lXOHnH5vhq9pJ9VjLsoqs1Z1XaVqRVPwgJiPIllEMIr5Le 0ATgBP+jBgZ7vjaju7C7tj7Jxpr6s7Eh3qXLQ= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1701395264; x=1702000064; h=cc:to:subject:message-id:date:from:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=U3HR5X5vF0aKqgSP9mL/Ey54FJixI2TYNBnr1Kpa3lA=; b=UwwwfXHouutg6imHcNHMOwqFxm++NUVOr8HFiXqVkerI2ihxS9vzO5Bf/ogepsewl/ E+zmiYBstgU7ph0/qx9KiOEM8mbFZEHx6p5ZSiH2g1HV7bXqkAOu25nzLBXlkBZVH5A3 kqyAJVDeS/l2S5DQ0Fpi8yOWjio5W7+izaLClR4vcMoJOZgXR3/cALUarMKF/ua9C3LN AAkBbTIaxIT0WbsJXvOD/C2mqbGD6eCmkmBbN6/r9peQRw3sDmRXb8E6B63oZ5xFHuO6 t5Eok8OlvMxnn/6HyqMTKa1yt/S9+LrPRmuwtrlD48OmQjOfHB6zAM0UROZS4EzqBZqI a1Pg== X-Gm-Message-State: AOJu0YynsWlTTiTpfkrV5G6prlGDbH2Nyg0PCuMEPEXXg6hBZ89+MSlX XvilWuGWjYMoqcgEvkoP1XTDcZAo9zx8pT3YIGV5QA== X-Received: by 2002:a17:906:d4:b0:a19:a1ba:8cbb with SMTP id 20-20020a17090600d400b00a19a1ba8cbbmr213556eji.89.1701395264644; Thu, 30 Nov 2023 17:47:44 -0800 (PST) MIME-Version: 1.0 From: Daniel J Blueman Date: Thu, 30 Nov 2023 20:47:33 -0500 Message-ID: Subject: bcachefs page fault oops after device evacuate/remove and unmount To: Kent Overstreet Cc: Linux Kernel , linux-bcachefs@vger.kernel.org Content-Type: text/plain; charset="UTF-8" X-Spam-Status: No, score=-0.9 required=5.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,T_SCC_BODY_TEXT_LINE autolearn=unavailable autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on howler.vger.email Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-Greylist: Sender passed SPF test, not delayed by milter-greylist-4.6.4 (howler.vger.email [0.0.0.0]); Thu, 30 Nov 2023 17:48:03 -0800 (PST) Hi Kent et al, On upstream bcachefs (master @ evilpiepirate.org/git/bcachefs.git) SHA f8a1ba26, I was able to develop a minimal reproducer [1] for a page not present oops I can provoke [2]. It appears we need further synchronisation during unmount. Let me know when there is a patch I can test, or for debug. Thanks, Dan -- [1] modprobe brd rd_size=536870912 rd_nr=2 bcachefs format -f /dev/ram0 /dev/ram1 mount -t bcachefs /dev/ram0:/dev/ram1 /mnt fio --group_reporting --ioengine=io_uring --directory=/mnt --size=16m --time_based --runtime=60s --iodepth=256 --verify_async=8 --bs=4k-64k --norandommap --random_distribution=zipf:0.5 --numjobs=16 --rw=randrw --name=A --direct=1 --name=B --direct=0 >/dev/null & bcachefs device evacuate /dev/ram0 bcachefs device remove --force --force-metadata /dev/ram1 bcachefs device remove --force --force-metadata /dev/ram1 kill %1 wait umount /mnt -- [2] BUG: kernel NULL pointer dereference, address: 0000000000000020 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP NOPTI CPU: 38 PID: 1778 Comm: umount Not tainted 6.7.0-rc2 #7 Hardware name: Supermicro AS -3014TS-i/H12SSL-i, BIOS 2.5 09/08/2022 RIP: 0010:bch2_journal_space_available (fs/bcachefs/journal_reclaim.c:190 (discriminator 1)) Code: f1 74 2d 4d 8b 97 a8 06 00 00 eb 15 8d 46 01 31 d2 f7 f7 41 89 97 bc 06 00 00 89 d6 44 39 ca 74 0f 89 f0 48 8b 8b d0 04 00 00 <49> 39 0c c2 72 dc 41 8b 97 b8 06 00 00 39 f2 74 49 4d 8b 8f a8 06 All code ======== 0: f1 int1 1: 74 2d je 0x30 3: 4d 8b 97 a8 06 00 00 mov 0x6a8(%r15),%r10 a: eb 15 jmp 0x21 c: 8d 46 01 lea 0x1(%rsi),%eax f: 31 d2 xor %edx,%edx 11: f7 f7 div %edi 13: 41 89 97 bc 06 00 00 mov %edx,0x6bc(%r15) 1a: 89 d6 mov %edx,%esi 1c: 44 39 ca cmp %r9d,%edx 1f: 74 0f je 0x30 21: 89 f0 mov %esi,%eax 23: 48 8b 8b d0 04 00 00 mov 0x4d0(%rbx),%rcx 2a:* 49 39 0c c2 cmp %rcx,(%r10,%rax,8) <-- trapping instruction 2e: 72 dc jb 0xc 30: 41 8b 97 b8 06 00 00 mov 0x6b8(%r15),%edx 37: 39 f2 cmp %esi,%edx 39: 74 49 je 0x84 3b: 4d rex.WRB 3c: 8b .byte 0x8b 3d: 8f .byte 0x8f 3e: a8 06 test $0x6,%al Code starting with the faulting instruction =========================================== 0: 49 39 0c c2 cmp %rcx,(%r10,%rax,8) 4: 72 dc jb 0xffffffffffffffe2 6: 41 8b 97 b8 06 00 00 mov 0x6b8(%r15),%edx d: 39 f2 cmp %esi,%edx f: 74 49 je 0x5a 11: 4d rex.WRB 12: 8b .byte 0x8b 13: 8f .byte 0x8f 14: a8 06 test $0x6,%al RSP: 0018:ffffc90020f63be0 EFLAGS: 00010202 RAX: 0000000000000004 RBX: ffff8881532c9dc0 RCX: 0000000000000013 RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000002000 RBP: ffffc90020f63c10 R08: 0000000000000000 R09: 0000000000000008 R10: 0000000000000000 R11: 0000000000000000 R12: ffff888153284400 R13: ffff888153280268 R14: 0000000000000001 R15: ffff88811668c000 FS: 00007f1a40c1c800(0000) GS:ffff88bf4eb00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000020 CR3: 00000001533de001 CR4: 0000000000770ef0 PKRU: 55555554 Call Trace: ? show_regs (arch/x86/kernel/dumpstack.c:479) ? __die (arch/x86/kernel/dumpstack.c:421 arch/x86/kernel/dumpstack.c:434) ? page_fault_oops (arch/x86/mm/fault.c:707) ? lock_acquire (kernel/locking/lockdep.c:467 (discriminator 4) kernel/locking/lockdep.c:5755 (discriminator 4) kernel/locking/lockdep.c:5718 (discriminator 4)) ? do_user_addr_fault (arch/x86/mm/fault.c:1264) ? exc_page_fault (./arch/x86/include/asm/paravirt.h:689 ./arch/x86/include/asm/irqflags.h:127 arch/x86/mm/fault.c:1513 arch/x86/mm/fault.c:1561) ? asm_exc_page_fault (./arch/x86/include/asm/idtentry.h:570) ? bch2_journal_space_available (fs/bcachefs/journal_reclaim.c:190 (discriminator 1)) bch2_journal_reclaim_fast (fs/bcachefs/journal_reclaim.c:313) bch2_journal_pin_drop (./include/linux/spinlock.h:391 fs/bcachefs/journal_reclaim.c:360) bch2_btree_complete_write (fs/bcachefs/btree_io.c:1724) bch2_fs_btree_cache_exit (fs/bcachefs/btree_cache.c:428 (discriminator 1)) bch2_fs_release (fs/bcachefs/super.c:523 fs/bcachefs/super.c:567) kobject_put (lib/kobject.c:689 lib/kobject.c:716 ./include/linux/kref.h:65 lib/kobject.c:733) bch2_fs_free (fs/bcachefs/super.c:633) bch2_kill_sb (fs/bcachefs/fs.c:1934) deactivate_locked_super (fs/super.c:486) deactivate_super (fs/super.c:519) cleanup_mnt (fs/namespace.c:139 fs/namespace.c:1257) __cleanup_mnt (fs/namespace.c:1264) task_work_run (kernel/task_work.c:182) exit_to_user_mode_prepare (./include/linux/resume_user_mode.h:49 kernel/entry/common.c:171 kernel/entry/common.c:204) syscall_exit_to_user_mode (kernel/entry/common.c:130 kernel/entry/common.c:298) do_syscall_64 (./arch/x86/include/asm/cpufeature.h:171 arch/x86/entry/common.c:97) ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:181) ? do_syscall_64 (./arch/x86/include/asm/cpufeature.h:171 arch/x86/entry/common.c:97) ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:181) ? do_syscall_64 (./arch/x86/include/asm/cpufeature.h:171 arch/x86/entry/common.c:97) ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:181) ? exit_to_user_mode_prepare (kernel/entry/common.c:212) ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:181) ? syscall_exit_to_user_mode (kernel/entry/common.c:299) ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:181) ? exit_to_user_mode_prepare (kernel/entry/common.c:212) ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:181) ? syscall_exit_to_user_mode (kernel/entry/common.c:299) ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:181) ? do_syscall_64 (./arch/x86/include/asm/cpufeature.h:171 arch/x86/entry/common.c:97) ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:181) ? do_syscall_64 (./arch/x86/include/asm/cpufeature.h:171 arch/x86/entry/common.c:97) entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:129) RIP: 0033:0x7f1a40b2920b Code: c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 f3 0f 1e fa 31 f6 e9 05 00 00 00 0f 1f 44 00 00 f3 0f 1e fa b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 05 c3 0f 1f 40 00 48 8b 15 d9 4b 0d 00 f7 d8 All code ======== 0: c3 ret 1: 66 2e 0f 1f 84 00 00 cs nopw 0x0(%rax,%rax,1) 8: 00 00 00 b: 0f 1f 40 00 nopl 0x0(%rax) f: f3 0f 1e fa endbr64 13: 31 f6 xor %esi,%esi 15: e9 05 00 00 00 jmp 0x1f 1a: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) 1f: f3 0f 1e fa endbr64 23: b8 a6 00 00 00 mov $0xa6,%eax 28: 0f 05 syscall 2a:* 48 3d 00 f0 ff ff cmp $0xfffffffffffff000,%rax <-- trapping instruction 30: 77 05 ja 0x37 32: c3 ret 33: 0f 1f 40 00 nopl 0x0(%rax) 37: 48 8b 15 d9 4b 0d 00 mov 0xd4bd9(%rip),%rdx # 0xd4c17 3e: f7 d8 neg %eax Code starting with the faulting instruction =========================================== 0: 48 3d 00 f0 ff ff cmp $0xfffffffffffff000,%rax 6: 77 05 ja 0xd 8: c3 ret 9: 0f 1f 40 00 nopl 0x0(%rax) d: 48 8b 15 d9 4b 0d 00 mov 0xd4bd9(%rip),%rdx # 0xd4bed 14: f7 d8 neg %eax RSP: 002b:00007fff13f8bca8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 000055c4aed6c5c0 RCX: 00007f1a40b2920b RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000055c4aed70d80 RBP: 000055c4aed6c6c0 R08: 000055c4aed68010 R09: 0000000000000007 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000055c4aed70d80 R14: 000055c4aed6c9d0 R15: 000055c4aed6c5c0 Modules linked in: brd cfg80211 ipmi_ssif binfmt_misc intel_rapl_msr intel_rapl_common amd64_edac edac_mce_amd kvm_amd kvm irqbypass wmi_bmof rapl nls_iso8859_1 ccp acpi_ipmi i2c_piix4 ptdma k10temp ipmi_si ipmi_devintf joydev input_leds ipmi_msghandler mac_hid dm_multipath msr efi_pstore dmi_sysfs ip_tables x_tables autofs4 btrfs blake2b_generic raid10 raid456 async_raid6_recov async_memcpy async_pq async_xor async_tx raid1 raid0 multipath linear hid_generic rndis_host usbhid cdc_ether usbnet hid mii crct10dif_pclmul ast crc32_pclmul i2c_algo_bit polyval_clmulni drm_shmem_helper polyval_generic ghash_clmulni_intel sha512_ssse3 drm_kms_helper sha256_ssse3 sha1_ssse3 nvme ahci drm tg3 libahci xhci_pci nvme_core xhci_pci_renesas wmi aesni_intel crypto_simd cryptd CR2: 0000000000000020 ---[ end trace 0000000000000000 ]--- RIP: 0010:bch2_journal_space_available (fs/bcachefs/journal_reclaim.c:190 (discriminator 1)) Code: f1 74 2d 4d 8b 97 a8 06 00 00 eb 15 8d 46 01 31 d2 f7 f7 41 89 97 bc 06 00 00 89 d6 44 39 ca 74 0f 89 f0 48 8b 8b d0 04 00 00 <49> 39 0c c2 72 dc 41 8b 97 b8 06 00 00 39 f2 74 49 4d 8b 8f a8 06 All code ======== 0: f1 int1 1: 74 2d je 0x30 3: 4d 8b 97 a8 06 00 00 mov 0x6a8(%r15),%r10 a: eb 15 jmp 0x21 c: 8d 46 01 lea 0x1(%rsi),%eax f: 31 d2 xor %edx,%edx 11: f7 f7 div %edi 13: 41 89 97 bc 06 00 00 mov %edx,0x6bc(%r15) 1a: 89 d6 mov %edx,%esi 1c: 44 39 ca cmp %r9d,%edx 1f: 74 0f je 0x30 21: 89 f0 mov %esi,%eax 23: 48 8b 8b d0 04 00 00 mov 0x4d0(%rbx),%rcx 2a:* 49 39 0c c2 cmp %rcx,(%r10,%rax,8) <-- trapping instruction 2e: 72 dc jb 0xc 30: 41 8b 97 b8 06 00 00 mov 0x6b8(%r15),%edx 37: 39 f2 cmp %esi,%edx 39: 74 49 je 0x84 3b: 4d rex.WRB 3c: 8b .byte 0x8b 3d: 8f .byte 0x8f 3e: a8 06 test $0x6,%al Code starting with the faulting instruction =========================================== 0: 49 39 0c c2 cmp %rcx,(%r10,%rax,8) 4: 72 dc jb 0xffffffffffffffe2 6: 41 8b 97 b8 06 00 00 mov 0x6b8(%r15),%edx d: 39 f2 cmp %esi,%edx f: 74 49 je 0x5a 11: 4d rex.WRB 12: 8b .byte 0x8b 13: 8f .byte 0x8f 14: a8 06 test $0x6,%al RSP: 0018:ffffc90020f63be0 EFLAGS: 00010202 RAX: 0000000000000004 RBX: ffff8881532c9dc0 RCX: 0000000000000013 RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000002000 RBP: ffffc90020f63c10 R08: 0000000000000000 R09: 0000000000000008 R10: 0000000000000000 R11: 0000000000000000 R12: ffff888153284400 R13: ffff888153280268 R14: 0000000000000001 R15: ffff88811668c000 FS: 00007f1a40c1c800(0000) GS:ffff88bf4eb00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000020 CR3: 00000001533de001 CR4: 0000000000770ef0 PKRU: 55555554 note: umount[1778] exited with irqs disabled note: umount[1778] exited with preempt_count 1 BUG: sleeping function called from invalid context at include/linux/percpu-rwsem.h:49 in_atomic(): 0, irqs_disabled(): 0, non_block: 0, pid: 1778, name: umount preempt_count: 0, expected: 0 RCU nest depth: 1, expected: 0 INFO: lockdep is turned off. CPU: 38 PID: 1778 Comm: umount Tainted: G D 6.7.0-rc2 #7 Hardware name: Supermicro AS -3014TS-i/H12SSL-i, BIOS 2.5 09/08/2022 Call Trace: dump_stack_lvl (lib/dump_stack.c:107) dump_stack (lib/dump_stack.c:114) __might_resched (kernel/sched/core.c:10152) __might_sleep (kernel/sched/core.c:10081) exit_signals (./include/linux/kernel.h:107 ./include/linux/percpu-rwsem.h:49 ./include/linux/cgroup-defs.h:772 kernel/signal.c:2996) do_exit (kernel/exit.c:832) ? _printk (kernel/printk/printk.c:2332) make_task_dead (kernel/exit.c:969) rewind_stack_and_make_dead (??:?) RIP: 0033:0x7f1a40b2920b Code: c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 f3 0f 1e fa 31 f6 e9 05 00 00 00 0f 1f 44 00 00 f3 0f 1e fa b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 05 c3 0f 1f 40 00 48 8b 15 d9 4b 0d 00 f7 d8 All code ======== 0: c3 ret 1: 66 2e 0f 1f 84 00 00 cs nopw 0x0(%rax,%rax,1) 8: 00 00 00 b: 0f 1f 40 00 nopl 0x0(%rax) f: f3 0f 1e fa endbr64 13: 31 f6 xor %esi,%esi 15: e9 05 00 00 00 jmp 0x1f 1a: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) 1f: f3 0f 1e fa endbr64 23: b8 a6 00 00 00 mov $0xa6,%eax 28: 0f 05 syscall 2a:* 48 3d 00 f0 ff ff cmp $0xfffffffffffff000,%rax <-- trapping instruction 30: 77 05 ja 0x37 32: c3 ret 33: 0f 1f 40 00 nopl 0x0(%rax) 37: 48 8b 15 d9 4b 0d 00 mov 0xd4bd9(%rip),%rdx # 0xd4c17 3e: f7 d8 neg %eax Code starting with the faulting instruction =========================================== 0: 48 3d 00 f0 ff ff cmp $0xfffffffffffff000,%rax 6: 77 05 ja 0xd 8: c3 ret 9: 0f 1f 40 00 nopl 0x0(%rax) d: 48 8b 15 d9 4b 0d 00 mov 0xd4bd9(%rip),%rdx # 0xd4bed 14: f7 d8 neg %eax RSP: 002b:00007fff13f8bca8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 000055c4aed6c5c0 RCX: 00007f1a40b2920b RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000055c4aed70d80 RBP: 000055c4aed6c6c0 R08: 000055c4aed68010 R09: 0000000000000007 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000055c4aed70d80 R14: 000055c4aed6c9d0 R15: 000055c4aed6c5c0 -- Daniel J Blueman