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[23.128.96.37]) by mx.google.com with ESMTPS id in24-20020a17090b439800b0028031f2f450si1347657pjb.22.2023.11.23.05.58.38 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 23 Nov 2023 05:58:39 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.37 as permitted sender) client-ip=23.128.96.37; Authentication-Results: mx.google.com; dkim=pass header.i=@incertum.net header.s=2019 header.b=MlEfQCQJ; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.37 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=REJECT sp=REJECT dis=NONE) header.from=incertum.net Received: from out1.vger.email (depot.vger.email [IPv6:2620:137:e000::3:0]) by snail.vger.email (Postfix) with ESMTP id 3BB38802C6B2; Thu, 23 Nov 2023 05:58:38 -0800 (PST) X-Virus-Status: Clean X-Virus-Scanned: clamav-milter 0.103.11 at snail.vger.email Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1345658AbjKWN61 (ORCPT + 99 others); Thu, 23 Nov 2023 08:58:27 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40072 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1345653AbjKWN60 (ORCPT ); Thu, 23 Nov 2023 08:58:26 -0500 X-Greylist: delayed 314 seconds by postgrey-1.37 at lindbergh.monkeyblade.net; Thu, 23 Nov 2023 05:58:31 PST Received: from mail.incertum.net (kaliadne.incertum.net [65.108.140.253]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9617F1B2 for ; Thu, 23 Nov 2023 05:58:31 -0800 (PST) Received: from [127.0.0.1] (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by mail.incertum.net (Postfix) with ESMTPS id B419E6902028 for ; Thu, 23 Nov 2023 14:53:15 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=incertum.net; s=2019; t=1700747595; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=qbr12/r+GUUvXPG2OVegiasrmw6Mi3PMvZlE4QMCkm4=; b=MlEfQCQJqO3pSWYKGenfv1q4s9F6el5OEfKkhgb5sQdmRmWG1uLAgzUT2RleTG8i9LD29k GfMMXkD/3vOnKu/hIcXf+Ocw3yets7ShC+Y+ZIH4g38UqgLKtjS4UBbEHE43ZoYv9L7hWh uCatI2ZnH8XA7guUy/q1+3YZcxe2oJk= Received: by pharmakeia.incertum.net (Postfix, from userid 1000) id 959B3C3A8F; Thu, 23 Nov 2023 14:53:15 +0100 (CET) Date: Thu, 23 Nov 2023 14:53:15 +0100 From: Stefan =?utf-8?Q?F=C3=B6rster?= To: linux-kernel@vger.kernel.org Subject: bcache: kernel NULL pointer dereference since 6.1.39 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Disposition: inline Content-Transfer-Encoding: quoted-printable X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_BLOCKED, SPF_HELO_NONE,SPF_PASS,T_SCC_BODY_TEXT_LINE,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net 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 (snail.vger.email [0.0.0.0]); Thu, 23 Nov 2023 05:58:38 -0800 (PST) Hello world, starting with kernel 6.1.39, we see the following error message with=20 heavy I/O loads. We needed to revert https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?h= =3Dv6.1.39&id=3D68118c339c6e1e16ae017bef160dbe28a27ae9c8 to make sure the systems don't suddenly get stuck. 1. Kernel 6.6.2-arch1-1 on Dell Latitude: [16816.214942] BUG: kernel NULL pointer dereference, address: 0000000000000= 080 [16816.214948] #PF: supervisor read access in kernel mode [16816.214951] #PF: error_code(0x0000) - not-present page [16816.214953] PGD 0 P4D 0=20 [16816.214956] Oops: 0000 [#1] PREEMPT SMP NOPTI [16816.214960] CPU: 7 PID: 83416 Comm: bcache_gc Tainted: P OE = 6.6.2-arch1-1 #1 11215f9ba7ddfb51644674a5b2ced71612c62fe9 [16816.214964] Hardware name: Dell Inc. Latitude 5431/06F77M, BIOS 1.17.0 0= 9/21/2023 [16816.214965] RIP: 0010:btree_node_free+0xf/0x160 [bcache] [16816.214999] Code: 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 = 90 90 90 90 90 90 90 90 90 0f 1f 44 00 00 55 53 48 89 fb 0f 1f 44 00 00 <48= > 8b 83 80 00 00 00 48 8d ab 90 00 00 00 48 39 98 60 c3 00 00 75 [16816.215001] RSP: 0018:ffffc90021777af8 EFLAGS: 00010207 [16816.215004] RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffff888515c= e0670 [16816.215006] RDX: 0000000000000000 RSI: ffff888515ce0680 RDI: 00000000000= 00000 [16816.215007] RBP: ffffc90021777bf0 R08: ffff88819476d9e0 R09: 00000000013= ffde8 [16816.215009] R10: 0000000000000000 R11: ffffc9000061b000 R12: ffffc900217= 77e40 [16816.215010] R13: ffffc90021777bf0 R14: ffffc90021777bd8 R15: ffff8881947= 6c000 [16816.215011] FS: 0000000000000000(0000) GS:ffff88886fdc0000(0000) knlGS:= 0000000000000000 [16816.215013] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [16816.215015] CR2: 0000000000000080 CR3: 0000000294a20000 CR4: 0000000000f= 50ee0 [16816.215017] PKRU: 55555554 [16816.215018] Call Trace: [16816.215021] [16816.215024] ? __die+0x23/0x70 [16816.215030] ? page_fault_oops+0x171/0x4e0 [16816.215035] ? __pfx_bch_ptr_bad+0x10/0x10 [bcache 33eebe64448bb81d5f2a1= 0179a48eb0a5bdb25a6] [16816.215059] ? exc_page_fault+0x7f/0x180 [16816.215065] ? asm_exc_page_fault+0x26/0x30 [16816.215070] ? btree_node_free+0xf/0x160 [bcache 33eebe64448bb81d5f2a101= 79a48eb0a5bdb25a6] [16816.215095] ? btree_node_free+0xa3/0x160 [bcache 33eebe64448bb81d5f2a10= 179a48eb0a5bdb25a6] [16816.215118] btree_gc_coalesce+0x2a7/0x890 [bcache 33eebe64448bb81d5f2a1= 0179a48eb0a5bdb25a6] [16816.215144] ? bch_extent_bad+0x81/0x190 [bcache 33eebe64448bb81d5f2a101= 79a48eb0a5bdb25a6] [16816.215172] btree_gc_recurse+0x130/0x390 [bcache 33eebe64448bb81d5f2a10= 179a48eb0a5bdb25a6] [16816.215197] ? btree_gc_mark_node+0x72/0x240 [bcache 33eebe64448bb81d5f2= a10179a48eb0a5bdb25a6] [16816.215221] bch_btree_gc+0x4b6/0x620 [bcache 33eebe64448bb81d5f2a10179a= 48eb0a5bdb25a6] [16816.215246] ? __pfx_autoremove_wake_function+0x10/0x10 [16816.215250] ? __pfx_bch_gc_thread+0x10/0x10 [bcache 33eebe64448bb81d5f2= a10179a48eb0a5bdb25a6] [16816.215272] bch_gc_thread+0x139/0x190 [bcache 33eebe64448bb81d5f2a10179= a48eb0a5bdb25a6] [16816.215295] ? __pfx_autoremove_wake_function+0x10/0x10 [16816.215298] kthread+0xe5/0x120 [16816.215302] ? __pfx_kthread+0x10/0x10 [16816.215306] ret_from_fork+0x31/0x50 [16816.215309] ? __pfx_kthread+0x10/0x10 [16816.215312] ret_from_fork_asm+0x1b/0x30 [16816.215318] [16816.215319] Modules linked in: bcache tun ccm rfcomm snd_seq_dummy snd_h= rtimer snd_seq nvidia(POE) typec_displayport cmac algif_hash algif_skcipher= af_alg bnep hid_sensor_custom hid_sensor_hub intel_ishtp_hid snd_hda_codec= _hdmi snd_sof_pci_intel_tgl snd_sof_intel_hda_common soundwire_intel snd_so= f_intel_hda_mlink soundwire_cadence snd_sof_intel_hda snd_sof_pci snd_sof_x= tensa_dsp snd_sof snd_sof_utils intel_uncore_frequency intel_uncore_frequen= cy_common snd_ctl_led snd_soc_hdac_hda r8153_ecm snd_hda_ext_core iwlmvm cd= c_ether snd_soc_acpi_intel_match usbnet snd_soc_acpi soundwire_generic_allo= cation soundwire_bus snd_soc_core x86_pkg_temp_thermal snd_compress snd_hda= _codec_realtek intel_powerclamp ac97_bus snd_hda_codec_generic dell_rbtn co= retemp btusb snd_pcm_dmaengine snd_usb_audio mac80211 btrtl snd_hda_intel k= vm_intel btintel snd_intel_dspcfg snd_intel_sdw_acpi snd_usbmidi_lib btbcm = dell_laptop snd_ump btmtk libarc4 snd_hda_codec uvcvideo kvm snd_rawmidi bl= uetooth snd_hda_core videobuf2_vmalloc hid_multitouch iwlwifi [16816.215367] dell_wmi snd_hwdep iTCO_wdt snd_seq_device uvc nls_iso8859_= 1 videobuf2_memops dell_smbios intel_pmc_bxt mei_hdcp mei_pxp spi_nor snd_p= cm processor_thermal_device_pci r8152 videobuf2_v4l2 dell_wmi_sysman irqbyp= ass intel_rapl_msr dcdbas vfat iTCO_vendor_support fat rapl intel_cstate in= tel_uncore psmouse pcspkr dell_wmi_ddv firmware_attributes_class ledtrig_au= dio videobuf2_common ucsi_acpi dell_wmi_descriptor processor_thermal_device= mousedev ecdh_generic snd_timer mii joydev mtd wmi_bmof e1000e cfg80211 pr= ocessor_thermal_rfim mei_me intel_lpss_pci i2c_i801 snd processor_thermal_m= box typec_ucsi intel_ish_ipc intel_lpss mei soundcore i2c_smbus processor_t= hermal_rapl rfkill thunderbolt typec idma64 intel_ishtp roles intel_rapl_co= mmon igen6_edac i2c_hid_acpi int3403_thermal i2c_hid int340x_thermal_zone i= ntel_hid int3400_thermal acpi_thermal_rel sparse_keymap acpi_tad acpi_pad m= ac_hid vboxnetflt(OE) vboxnetadp(OE) vboxdrv(OE) v4l2loopback(OE) videodev = mc i2c_dev crypto_user fuse loop ip_tables x_tables ext4 [16816.215420] crc32c_generic crc16 mbcache jbd2 dm_crypt cbc encrypted_ke= ys trusted asn1_encoder tee usbhid i915 dm_mod crct10dif_pclmul crc32_pclmu= l crc32c_intel polyval_clmulni i2c_algo_bit polyval_generic serio_raw rtsx_= pci_sdmmc drm_buddy gf128mul atkbd ghash_clmulni_intel ttm mmc_core sha512_= ssse3 libps2 vivaldi_fmap intel_gtt aesni_intel nvme crypto_simd drm_displa= y_helper video nvme_core cryptd spi_intel_pci rtsx_pci spi_intel i8042 xhci= _pci cec nvme_common xhci_pci_renesas serio wmi [16816.215451] CR2: 0000000000000080 [16816.215453] ---[ end trace 0000000000000000 ]--- [16816.215455] RIP: 0010:btree_node_free+0xf/0x160 [bcache] [16816.215478] Code: 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 = 90 90 90 90 90 90 90 90 90 0f 1f 44 00 00 55 53 48 89 fb 0f 1f 44 00 00 <48= > 8b 83 80 00 00 00 48 8d ab 90 00 00 00 48 39 98 60 c3 00 00 75 [16816.215480] RSP: 0018:ffffc90021777af8 EFLAGS: 00010207 [16816.215481] RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffff888515c= e0670 [16816.215483] RDX: 0000000000000000 RSI: ffff888515ce0680 RDI: 00000000000= 00000 [16816.215484] RBP: ffffc90021777bf0 R08: ffff88819476d9e0 R09: 00000000013= ffde8 [16816.215486] R10: 0000000000000000 R11: ffffc9000061b000 R12: ffffc900217= 77e40 [16816.215487] R13: ffffc90021777bf0 R14: ffffc90021777bd8 R15: ffff8881947= 6c000 [16816.215488] FS: 0000000000000000(0000) GS:ffff88886fdc0000(0000) knlGS:= 0000000000000000 [16816.215490] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [16816.215492] CR2: 0000000000000080 CR3: 0000000294a20000 CR4: 0000000000f= 50ee0 [16816.215493] PKRU: 55555554 [16816.215494] note: bcache_gc[83416] exited with irqs disabled 2. Kernel 6.1.55 (Debian 6.1.0-13) on HPE Gen11: [60654.670443] BUG: kernel NULL pointer dereference, address: 0000000000000= 080 [60654.677474] #PF: supervisor read access in kernel mode [60654.682651] #PF: error_code(0x0000) - not-present page [60654.687825] PGD 0=20 [60654.689852] Oops: 0000 [#1] PREEMPT SMP NOPTI [60654.694240] CPU: 16 PID: 146330 Comm: bcache_gc Tainted: G W = 6.1.0-13-amd64 #1 Debian 6.1.55-1 [60654.704399] Hardware name: HPE ProLiant DL380 Gen11/ProLiant DL380 Gen11= , BIOS 1.48 10/19/2023 [60654.713071] RIP: 0010:btree_node_free+0xf/0x160 [bcache] [60654.718437] Code: ff 48 89 d8 5b 5d 41 5c 41 5d c3 cc cc cc cc 66 66 2e = 0f 1f 84 00 00 00 00 00 90 0f 1f 44 00 00 55 53 48 89 fb 0f 1f 44 00 00 <48= > 8b 83 80 00 00 00 48 39 98 70 c3 00 00 0f 84 34 01 00 00 48 8d [60654.737342] RSP: 0018:ff77daed34cc3b18 EFLAGS: 00010207 [60654.742604] RAX: 0000000080000000 RBX: 0000000000000000 RCX: 00000000000= 00000 [60654.749790] RDX: 0000000000000001 RSI: ff2971b8de800690 RDI: 00000000000= 00000 [60654.756975] RBP: ff77daed34cc3c10 R08: ff2971d852dc65e0 R09: ff2971b8de8= 00000 [60654.764536] R10: 0000000000000000 R11: ff77daed34a4d000 R12: ff77daed34c= c3e60 [60654.771987] R13: ff77daed34cc3c10 R14: ff77daed34cc3c00 R15: ff2971d8510= 96400 [60654.779410] FS: 0000000000000000(0000) GS:ff2971f7bf400000(0000) knlGS:= 0000000000000000 [60654.787784] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [60654.793794] CR2: 0000000000000080 CR3: 0000000150610002 CR4: 00000000007= 71ee0 [60654.801203] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 00000000000= 00000 [60654.808609] DR3: 0000000000000000 DR6: 00000000fffe07f0 DR7: 00000000000= 00400 [60654.816009] PKRU: 55555554 [60654.818949] Call Trace: [60654.821623] [60654.823950] ? __die_body.cold+0x1a/0x1f [60654.828110] ? page_fault_oops+0xd2/0x2b0 [60654.832352] ? exc_page_fault+0x70/0x170 [60654.836505] ? asm_exc_page_fault+0x22/0x30 [60654.840922] ? btree_node_free+0xf/0x160 [bcache] [60654.845863] ? up_write+0x32/0x60 [60654.849396] btree_gc_coalesce+0x2aa/0x890 [bcache] [60654.854512] ? bch_extent_bad+0x70/0x170 [bcache] [60654.859452] btree_gc_recurse+0x130/0x390 [bcache] [60654.864475] ? btree_gc_mark_node+0x72/0x230 [bcache] [60654.869758] bch_btree_gc+0x5da/0x600 [bcache] [60654.874428] ? cpuusage_read+0x10/0x10 [60654.878390] ? bch_btree_gc+0x600/0x600 [bcache] [60654.883232] bch_gc_thread+0x135/0x180 [bcache] [60654.887986] ? cpuusage_read+0x10/0x10 [60654.891944] kthread+0xe6/0x110 [60654.895290] ? kthread_complete_and_exit+0x20/0x20 [60654.900296] ret_from_fork+0x1f/0x30 [60654.904079] [60654.906455] Modules linked in: bonding tls cfg80211 rfkill intel_rapl_ms= r intel_rapl_common intel_uncore_frequency intel_uncore_frequency_common i1= 0nm_edac nfit binfmt_misc libnvdimm x86_pkg_temp_thermal intel_powerclamp i= pt_REJECT nf_reject_ipv4 coretemp xt_comment nft_compat nf_tables nfnetlink= nls_ascii nls_cp437 kvm_intel vfat ipmi_ssif fat kvm irqbypass ghash_clmul= ni_intel sha512_ssse3 sha512_generic aesni_intel crypto_simd cryptd mgag200= drm_shmem_helper pmt_telemetry pmt_crashlog rapl intel_cstate acpi_ipmi ev= dev intel_sdsi pmt_class idxd hpwdt mei_me isst_if_mbox_pci isst_if_mmio dr= m_kms_helper intel_uncore pcspkr isst_if_common mei watchdog hpilo i2c_algo= _bit ipmi_si idxd_bus acpi_tad intel_vsec sg acpi_power_meter button ipmi_d= evintf ipmi_msghandler loop fuse efi_pstore drm configfs efivarfs ip_tables= x_tables autofs4 ext4 crc16 mbcache jbd2 btrfs blake2b_generic xor raid6_p= q zstd_compress libcrc32c crc32c_generic ses enclosure bcache sd_mod scsi_t= ransport_sas dm_mod nvme [60654.906508] nvme_core xhci_pci t10_pi megaraid_sas ehci_pci xhci_hcd eh= ci_hcd crc64_rocksoft crc64 tg3 crc_t10dif scsi_mod usbcore crct10dif_gener= ic crc32_pclmul crc32c_intel crct10dif_pclmul libphy scsi_common usb_common= crct10dif_common wmi [60655.017712] CR2: 0000000000000080 [60655.021262] ---[ end trace 0000000000000000 ]--- [60655.173744] RIP: 0010:btree_node_free+0xf/0x160 [bcache] [60655.179337] Code: ff 48 89 d8 5b 5d 41 5c 41 5d c3 cc cc cc cc 66 66 2e = 0f 1f 84 00 00 00 00 00 90 0f 1f 44 00 00 55 53 48 89 fb 0f 1f 44 00 00 <48= > 8b 83 80 00 00 00 48 39 98 70 c3 00 00 0f 84 34 01 00 00 48 8d [60655.198649] RSP: 0018:ff77daed34cc3b18 EFLAGS: 00010207 [60655.204121] RAX: 0000000080000000 RBX: 0000000000000000 RCX: 00000000000= 00000 [60655.211515] RDX: 0000000000000001 RSI: ff2971b8de800690 RDI: 00000000000= 00000 [60655.218908] RBP: ff77daed34cc3c10 R08: ff2971d852dc65e0 R09: ff2971b8de8= 00000 [60655.226302] R10: 0000000000000000 R11: ff77daed34a4d000 R12: ff77daed34c= c3e60 [60655.233696] R13: ff77daed34cc3c10 R14: ff77daed34cc3c00 R15: ff2971d8510= 96400 [60655.241086] FS: 0000000000000000(0000) GS:ff2971f7bf400000(0000) knlGS:= 0000000000000000 [60655.249438] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [60655.255432] CR2: 0000000000000080 CR3: 0000000150610002 CR4: 00000000007= 71ee0 [60655.262825] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 00000000000= 00000 [60655.270218] DR3: 0000000000000000 DR6: 00000000fffe07f0 DR7: 00000000000= 00400 [60655.277607] PKRU: 55555554 [60655.280543] note: bcache_gc[146330] exited with irqs disabled Reproducer for us: dd if=3D/dev/zero of=3Dloop0 bs=3D1M count=3D1024 dd if=3D/dev/zero of=3Dloop1 bs=3D1M count=3D10240 losetup loop0 loop0 losetup loop1 loop1 make-bcache -C /dev/loop0 -B /dev/loop1 --writeback mkfs.ext4 /dev/bcache0 mount /dev/bcache0 /mnt Then run fio with: [global] bs=3D4k ioengine=3Dlibaio iodepth=3D4 size=3D8g direct=3D1 runtime=3D60 directory=3D/mnt filename=3Dssd.test.file [seq-write] rw=3Dwrite stonewall [rand-write] rw=3Drandwrite stonewall [seq-read] rw=3Dread stonewall [rand-read] rw=3Drandread stonewall Cheers, Stefan