ci2 starts bisection 2024-04-10 07:25:29.013056014 +0000 UTC m=+43350.987460574 bisecting cause commit starting from fe46a7dd189e25604716c03576d05ac8a5209743 building syzkaller on 171ec3714ee4886a3f5ecbfe71f63c8f81c7fd7c ensuring issue is reproducible on original commit fe46a7dd189e25604716c03576d05ac8a5209743 testing commit fe46a7dd189e25604716c03576d05ac8a5209743 gcc compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 kernel signature: d5d153739c36e2ef5302ec589a742074d63600f70585b03ae8f0bb9963c4b973 all runs: crashed: possible deadlock in snd_pcm_period_elapsed representative crash: possible deadlock in snd_pcm_period_elapsed, types: [LOCKDEP] check whether we can drop unnecessary instrumentation disabling configs for [UBSAN BUG KASAN ATOMIC_SLEEP HANG LEAK], they are not needed testing commit fe46a7dd189e25604716c03576d05ac8a5209743 gcc compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 kernel signature: eab6a2337080c5bc215a20d2b49fdb2f79c4846493721c1162566157b8f36d2f all runs: crashed: possible deadlock in snd_pcm_period_elapsed representative crash: possible deadlock in snd_pcm_period_elapsed, types: [LOCKDEP] the bug reproduces without the instrumentation disabling configs for [ATOMIC_SLEEP HANG LEAK UBSAN BUG KASAN], they are not needed kconfig minimization: base=3971 full=7979 leaves diff=2012 split chunks (needed=false): <2012> split chunk #0 of len 2012 into 5 parts testing without sub-chunk 1/5 disabling configs for [ATOMIC_SLEEP HANG LEAK UBSAN BUG KASAN], they are not needed testing commit fe46a7dd189e25604716c03576d05ac8a5209743 gcc compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 kernel signature: 6062581c533873aa928439f3e0f99af604ba019b8dc5e656e6cff16f8938f898 all runs: crashed: possible deadlock in snd_pcm_period_elapsed representative crash: possible deadlock in snd_pcm_period_elapsed, types: [LOCKDEP] the chunk can be dropped testing without sub-chunk 2/5 disabling configs for [HANG LEAK UBSAN BUG KASAN ATOMIC_SLEEP], they are not needed testing commit fe46a7dd189e25604716c03576d05ac8a5209743 gcc compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 kernel signature: 70b889ab2819cdf7106d41f8230d4fdbf0d0ef58d136c1696eccfca00555e939 all runs: crashed: possible deadlock in snd_pcm_period_elapsed representative crash: possible deadlock in snd_pcm_period_elapsed, types: [LOCKDEP] the chunk can be dropped testing without sub-chunk 3/5 disabling configs for [KASAN ATOMIC_SLEEP HANG LEAK UBSAN BUG], they are not needed testing commit fe46a7dd189e25604716c03576d05ac8a5209743 gcc compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 kernel signature: 3968ac58b657ec8a5ce9c9eddfbb09ab00bc84514639ba80995a2c6d0fce478c all runs: crashed: possible deadlock in snd_pcm_period_elapsed representative crash: possible deadlock in snd_pcm_period_elapsed, types: [LOCKDEP] the chunk can be dropped testing without sub-chunk 4/5 disabling configs for [ATOMIC_SLEEP HANG LEAK UBSAN BUG KASAN], they are not needed testing commit fe46a7dd189e25604716c03576d05ac8a5209743 gcc compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 kernel signature: 6801dce3786bd643ff03dce1e72fb7a036d60d5b503a5c3ea9fd5b56acd73d43 all runs: OK false negative chance: 0.000 testing without sub-chunk 5/5 disabling configs for [BUG KASAN ATOMIC_SLEEP HANG LEAK UBSAN], they are not needed testing commit fe46a7dd189e25604716c03576d05ac8a5209743 gcc compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 kernel signature: cbeac0bd194285cd0fc091013f986ca304a798953b09551307bcfb979484cda5 all runs: crashed: possible deadlock in snd_pcm_period_elapsed representative crash: possible deadlock in snd_pcm_period_elapsed, types: [LOCKDEP] the chunk can be dropped minimized to 403 configs; suspects: [AF_RXRPC ARCH_ENABLE_MEMORY_HOTREMOVE ATM AX25 CFG80211 CMA DAX DLM DVB_CORE ENCRYPTED_KEYS EXTCON GENEVE GPIOLIB HAMRADIO HAVE_CLK HID_SENSOR_HUB HID_SMARTJOYPLUS HID_THRUSTMASTER IIO INFINIBAND INFINIBAND_ADDR_TRANS INFINIBAND_IPOIB INFINIBAND_USER_ACCESS INFINIBAND_VIRT_DMA INPUT_TABLET INPUT_TOUCHSCREEN IP_SCTP L2TP LIBNVDIMM MEDIA_COMMON_OPTIONS MEDIA_DIGITAL_TV_SUPPORT MEDIA_RADIO_SUPPORT MEDIA_SDR_SUPPORT MEDIA_SUPPORT MEDIA_USB_SUPPORT MEMORY_HOTPLUG MEMORY_HOTREMOVE MFD_DLN2 MFD_RETU MMC MTD MTD_UBI NETFILTER_CONNCOUNT NET_IPGRE NET_IPGRE_DEMUX NFS_V4_1 NF_TPROXY_IPV4 NF_TPROXY_IPV6 NILFS2_FS NLMON NLS_CODEPAGE_1250 NLS_CODEPAGE_1251 NLS_CODEPAGE_737 NLS_CODEPAGE_775 NLS_CODEPAGE_850 NLS_CODEPAGE_852 NLS_CODEPAGE_855 NLS_CODEPAGE_857 NLS_CODEPAGE_860 NLS_CODEPAGE_861 NLS_CODEPAGE_862 NLS_CODEPAGE_863 NLS_CODEPAGE_864 NLS_CODEPAGE_865 NLS_CODEPAGE_866 NLS_CODEPAGE_869 NLS_CODEPAGE_874 NLS_CODEPAGE_932 NLS_CODEPAGE_936 NLS_CODEPAGE_949 NLS_CODEPAGE_950 NLS_ISO8859_13 NLS_ISO8859_14 NLS_ISO8859_15 NLS_ISO8859_2 NLS_ISO8859_3 NLS_ISO8859_4 NLS_ISO8859_5 NLS_ISO8859_6 NLS_ISO8859_7 NLS_ISO8859_8 NLS_ISO8859_9 NLS_KOI8_R NLS_KOI8_U NLS_MAC_CELTIC NLS_MAC_CENTEURO NLS_MAC_CROATIAN NLS_MAC_CYRILLIC NLS_MAC_GAELIC NLS_MAC_GREEK NLS_MAC_ICELAND NLS_MAC_INUIT NLS_MAC_ROMAN NLS_MAC_ROMANIAN NLS_MAC_TURKISH NLS_UCS2_UTILS NOP_USB_XCEIV NOZOMI NTFS3_FS NTFS3_FS_POSIX_ACL NTFS3_LZX_XPRESS NULL_TTY NUMA_BALANCING NUMA_BALANCING_DEFAULT_ENABLED NUMA_EMU NUMA_KEEP_MEMINFO NVDIMM_DAX NVDIMM_KEYS NVDIMM_PFN NVME_CORE NVME_FABRICS NVME_FC NVME_MULTIPATH NVME_RDMA NVME_TARGET NVME_TARGET_FC NVME_TARGET_FCLOOP NVME_TARGET_LOOP NVME_TARGET_RDMA NVME_TARGET_TCP NVME_TCP N_GSM N_HDLC OCFS2_DEBUG_FS OCFS2_FS OCFS2_FS_O2CB OCFS2_FS_STATS OCFS2_FS_USERSPACE_CLUSTER OF_GPIO OF_PMEM OMFS_FS OPENVSWITCH OPENVSWITCH_GENEVE OPENVSWITCH_GRE OPENVSWITCH_VXLAN ORANGEFS_FS OSF_PARTITION OVERLAY_FS OVERLAY_FS_DEBUG OVERLAY_FS_INDEX OVERLAY_FS_REDIRECT_ALWAYS_FOLLOW OVERLAY_FS_REDIRECT_DIR PACKET_DIAG PAGE_IDLE_FLAG PAGE_POOL PAGE_REPORTING PAHOLE_HAS_BTF_TAG PAHOLE_HAS_LANG_EXCLUDE PAHOLE_HAS_SPLIT_BTF PARPORT PARPORT_NOT_PC PARTITION_ADVANCED PCCARD PCCARD_NONSTATIC PCIEAER PCI_ENDPOINT PCI_IOV PCMCIA PCMCIA_LOAD_CIS PERCPU_STATS PERSISTENT_KEYRINGS PHONET PHYLINK PHY_CPCAP_USB PHY_QCOM_USB_HS PHY_QCOM_USB_HSIC PHY_SAMSUNG_USB2 PHY_TUSB1210 PKCS7_TEST_KEY PKCS8_PRIVATE_KEY_PARSER PM_CLK PNFS_BLOCK PNFS_FILE_LAYOUT PNFS_FLEXFILE_LAYOUT PPP PPPOATM PPPOE PPPOE_HASH_BITS_4 PPPOL2TP PPP_ASYNC PPP_BSDCOMP PPP_DEFLATE PPP_FILTER PPP_MPPE PPP_MULTILINK PPP_SYNC_TTY PPTP PREEMPT PREEMPT_NOTIFIERS PRISM2_USB PROC_CHILDREN PSI PSTORE PSTORE_COMPRESS QCOM_QMI_HELPERS QNX4FS_FS QNX6FS_FS QRTR QRTR_TUN R8712U RADIO_ADAPTERS RADIO_SHARK RADIO_SHARK2 RADIO_TEA575X RAID6_PQ RAID_ATTRS RC_ATI_REMOTE RC_CORE RC_DEVICES RDMA_RXE RDMA_SIW RDS RDS_RDMA RDS_TCP READ_ONLY_THP_FOR_FS REALTEK_AUTOPM REED_SOLOMON REED_SOLOMON_DEC8 REGMAP REGMAP_I2C REGMAP_IRQ REGMAP_MMIO REGMAP_SPI REGULATOR REGULATOR_TWL4030 REISERFS_FS REISERFS_FS_POSIX_ACL REISERFS_FS_SECURITY REISERFS_FS_XATTR REISERFS_PROC_INFO RESET_CONTROLLER RFKILL RFKILL_INPUT RFKILL_LEDS RMI4_2D_SENSOR RMI4_CORE RMI4_F03 RMI4_F03_SERIO RMI4_F11 RMI4_F12 RMI4_F30 ROMFS_BACKED_BY_BOTH ROMFS_FS ROMFS_ON_BLOCK ROMFS_ON_MTD ROSE RTC_DRV_HID_SENSOR_TIME RXKAD SCHED_CORE SCREEN_INFO SCSI_FC_ATTRS SCSI_HPSA SCSI_ISCSI_ATTRS SCSI_LOGGING SCSI_NETLINK SCSI_SAS_ATA SCSI_SAS_ATTRS SCSI_SAS_LIBSAS SCSI_SCAN_ASYNC SCSI_SRP_ATTRS SCTP_COOKIE_HMAC_MD5 SCTP_COOKIE_HMAC_SHA1 SCTP_DEFAULT_COOKIE_HMAC_MD5 SECONDARY_TRUSTED_KEYRING SECURITY_INFINIBAND SECURITY_NETWORK_XFRM SECURITY_SMACK_NETFILTER SERIAL_DEV_BUS SERIAL_DEV_CTRL_TTYPORT SERIAL_MCTRL_GPIO SGI_PARTITION SIGNATURE SIGNED_PE_FILE_VERIFICATION SLHC SLIP SLIP_COMPRESSED SLIP_MODE_SLIP6 SLIP_SMART SMARTJOYPLUS_FF SMBFS SMC SMC_DIAG SMSC_PHY SMS_SIANO_MDTV SMS_SIANO_RC SMS_USB_DRV SND SND_ALOOP SND_BCD2000 SND_CTL_FAST_LOOKUP SND_CTL_LED SND_DEBUG SND_DMA_SGBUF SND_DRIVERS SND_DUMMY SND_DYNAMIC_MINORS SND_HDA SND_HDA_CODEC_ANALOG SND_HDA_CODEC_CA0110 SND_HDA_CODEC_CA0132 SND_HDA_CODEC_CIRRUS SND_HDA_CODEC_CMEDIA SND_HDA_CODEC_CONEXANT SND_HDA_CODEC_HDMI SND_HDA_CODEC_REALTEK SND_HDA_CODEC_SI3054 SND_HDA_CODEC_SIGMATEL SND_HDA_CODEC_VIA SND_HDA_COMPONENT SND_HDA_CORE SND_HDA_GENERIC SND_HDA_GENERIC_LEDS SND_HDA_HWDEP SND_HDA_I915 SND_HDA_INPUT_BEEP SND_HDA_INTEL SND_HDA_PATCH_LOADER SND_HDA_RECONFIG SND_HDA_SCODEC_COMPONENT SND_HRTIMER SND_HWDEP SND_INTEL_DSP_CONFIG SND_INTEL_NHLT SND_INTEL_SOUNDWIRE_ACPI SND_JACK SND_JACK_INPUT_DEV SND_MIXER_OSS SND_OSSEMUL SND_PCI SND_PCM SND_PCMCIA SND_PCM_OSS SND_PCM_OSS_PLUGINS SND_PCM_TIMER SND_PCM_XRUN_DEBUG SND_PROC_FS SND_RAWMIDI SND_SEQUENCER SND_SEQUENCER_OSS SND_SEQ_DEVICE SND_SEQ_DUMMY SND_SEQ_HRTIMER_DEFAULT SND_SEQ_MIDI SND_SEQ_MIDI_EVENT SND_SEQ_VIRMIDI SND_SOC SND_SOC_I2C_AND_SPI SND_SUPPORT_OLD_API SND_TIMER SND_USB SND_USB_6FIRE SND_USB_AUDIO SND_USB_AUDIO_USE_MEDIA_CONTROLLER SND_USB_CAIAQ SND_USB_CAIAQ_INPUT SND_USB_HIFACE SND_USB_LINE6 SND_USB_POD SND_USB_PODHD SND_USB_TONEPORT SND_USB_UA101 SND_USB_US122L SND_USB_USX2Y SND_USB_VARIAX SND_VERBOSE_PROCFS SND_VIRMIDI SND_VIRTIO SND_VMASTER SND_X86 SOCK_VALIDATE_XMIT SOLARIS_X86_PARTITION SONY_FF SOUND SOUNDWIRE SOUND_OSS_CORE SOUND_OSS_CORE_PRECLAIM SPI SPI_DLN2 SPI_DYNAMIC SPI_MASTER SQUASHFS SQUASHFS_4K_DEVBLK_SIZE SQUASHFS_COMPILE_DECOMP_SINGLE SQUASHFS_DECOMP_SINGLE SQUASHFS_FILE_DIRECT SQUASHFS_LZ4 SQUASHFS_LZO SQUASHFS_XATTR SQUASHFS_XZ SQUASHFS_ZLIB SQUASHFS_ZSTD SSB SSB_PCIHOST_POSSIBLE SSB_PCMCIAHOST_POSSIBLE SSB_SDIOHOST_POSSIBLE STAGING STP STREAM_PARSER SUNRPC_BACKCHANNEL SUN_PARTITION SW_SYNC SYSFB SYSV68_PARTITION SYSV_FS TABLET_USB_ACECAD TABLET_USB_AIPTEK TABLET_USB_HANWANG TABLET_USB_KBTAB TABLET_USB_PEGASUS TAHVO_USB TAHVO_USB_HOST_BY_DEFAULT TASKS_TRACE_RCU TCG_CRB TCG_TIS TCG_TIS_CORE TCG_TPM TCP_CONG_BBR TCP_CONG_BIC TCP_CONG_CDG TCP_CONG_DCTCP TCP_CONG_HSTCP TCP_CONG_HTCP TCP_CONG_HYBLA TCP_CONG_ILLINOIS TCP_CONG_LP TCP_CONG_NV TCP_CONG_SCALABLE TCP_CONG_VEGAS TCP_CONG_VENO TCP_CONG_WESTWOOD TCP_CONG_YEAH TEXTSEARCH TEXTSEARCH_BM TEXTSEARCH_FSM TEXTSEARCH_KMP THERMAL_NETLINK THP_SWAP THRUSTMASTER_FF TIPC TIPC_CRYPTO TIPC_DIAG TIPC_MEDIA_IB TIPC_MEDIA_UDP TLS TLS_TOE TMPFS_QUOTA TOUCHSCREEN_SUR40 TOUCHSCREEN_USB_3M TOUCHSCREEN_USB_COMPOSITE TOUCHSCREEN_USB_DMC_TSC10 TOUCHSCREEN_USB_E2I TOUCHSCREEN_USB_EASYTOUCH TOUCHSCREEN_USB_EGALAX TOUCHSCREEN_USB_ELO TOUCHSCREEN_USB_ETT_TC45USB TOUCHSCREEN_USB_ETURBO TOUCHSCREEN_USB_GENERAL_TOUCH TOUCHSCREEN_USB_GOTOP TOUCHSCREEN_USB_GUNZE TOUCHSCREEN_USB_IDEALTEK TOUCHSCREEN_USB_IRTOUCH TOUCHSCREEN_USB_ITM TOUCHSCREEN_USB_JASTEC TOUCHSCREEN_USB_NEXIO TOUCHSCREEN_USB_PANJIT TOUCHSCREEN_USB_ZYTRONIC TRANSPARENT_HUGEPAGE TRANSPARENT_HUGEPAGE_MADVISE TTPCI_EEPROM TTY_PRINTK TUN_VNET_CROSS_LE TWL4030_CORE TYPEC TYPEC_FUSB302 TYPEC_TCPCI TYPEC_TCPM TYPEC_TPS6598X TYPEC_UCSI UBIFS_ATIME_SUPPORT UBIFS_FS UBIFS_FS_ADVANCED_COMPR UBIFS_FS_LZO UBIFS_FS_SECURITY UBIFS_FS_XATTR UBIFS_FS_ZLIB UBIFS_FS_ZSTD UBSAN_SIGNED_WRAP UCSI_ACPI UDF_FS UDMABUF UFS_FS UFS_FS_WRITE UHID ULTRIX_PARTITION UNICODE UNIXWARE_DISKLABEL UNIX_DIAG USB4 USB4_NET USBIP_CORE USBIP_HOST USBIP_VHCI_HCD USBIP_VUDC USBPCWATCHDOG USB_ACM USB_ADUTUX USB_AIRSPY USB_ALI_M5632 USB_AN2720 USB_APPLEDISPLAY USB_ARMLINUX USB_BDC_UDC USB_BELKIN USB_C67X00_HCD USB_CATC USB_CDC_PHONET USB_CHAOSKEY USB_CHIPIDEA USB_CHIPIDEA_HOST USB_CHIPIDEA_PCI USB_CHIPIDEA_UDC USB_CONFIGFS USB_CONFIGFS_ACM USB_CONFIGFS_ECM USB_CONFIGFS_ECM_SUBSET USB_DWC2 USB_GADGET USB_MUSB_HDRC USB_NET_CDC_SUBSET USB_ROLE_SWITCH USB_STORAGE_REALTEK USB_ULPI_BUS USB_USBNET VIDEO_DEV VXLAN WIRELESS WLAN ZONE_DEVICE] disabling configs for [ATOMIC_SLEEP HANG LEAK UBSAN BUG KASAN], they are not needed picked [v6.8 v6.7 v6.6 v6.4 v6.2 v6.0 v5.18 v5.16 v5.13 v5.10 v5.7 v5.4 v5.1 v4.19] out of 31 release tags testing release v6.8 testing commit e8f897f4afef0031fe618a8e94127a0934896aba gcc compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 kernel signature: b72fca4b57eeebe185e0cc99cb22c91169e5829b0a18c2fc1c672b8cbfb2ecd1 all runs: OK false negative chance: 0.000 # git bisect start fe46a7dd189e25604716c03576d05ac8a5209743 e8f897f4afef0031fe618a8e94127a0934896aba Bisecting: 3748 revisions left to test after this (roughly 12 steps) [9187210eee7d87eea37b45ea93454a88681894a4] Merge tag 'net-next-6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next testing commit 9187210eee7d87eea37b45ea93454a88681894a4 gcc compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 kernel signature: 29e588fdd095ebc42badc1c4413818fe99eeb7aa7e6db3c2e079d36be94404b8 all runs: OK false negative chance: 0.000 # git bisect good 9187210eee7d87eea37b45ea93454a88681894a4 Bisecting: 2295 revisions left to test after this (roughly 11 steps) [119b225f01e4d3ce974cd3b4d982c76a380c796d] Merge tag 'amd-drm-next-6.9-2024-03-08-1' of https://gitlab.freedesktop.org/agd5f/linux into drm-next testing commit 119b225f01e4d3ce974cd3b4d982c76a380c796d gcc compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 kernel signature: 009def8888dbbd2fdbfebc28164fc7c344314bf1ab8b5d44c46eaff21e8e96eb all runs: OK false negative chance: 0.000 # git bisect good 119b225f01e4d3ce974cd3b4d982c76a380c796d Bisecting: 1148 revisions left to test after this (roughly 10 steps) [70ef654469b371d0a71bcf967fa3dcbca05d4b25] Merge tag 'efi-next-for-v6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi testing commit 70ef654469b371d0a71bcf967fa3dcbca05d4b25 gcc compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 kernel signature: fe341d542fcc580fb610facb332d94a73178acb88a469f0d25308431910ee329 all runs: OK false negative chance: 0.000 # git bisect good 70ef654469b371d0a71bcf967fa3dcbca05d4b25 Bisecting: 589 revisions left to test after this (roughly 9 steps) [8403ce70be339d462892a2b935ae30ee52416f92] Merge tag 'mfd-next-6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd testing commit 8403ce70be339d462892a2b935ae30ee52416f92 gcc compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 kernel signature: 79c04e0e5cdb4ed8caa6f5ba5f5f9978271ffab430b63b01d646f38a750f1262 all runs: OK false negative chance: 0.000 # git bisect good 8403ce70be339d462892a2b935ae30ee52416f92 Bisecting: 266 revisions left to test after this (roughly 8 steps) [f5d9ddf1214bf878ca69c905c2f410c5b51de99c] Merge tag 'asoc-v6.9' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus testing commit f5d9ddf1214bf878ca69c905c2f410c5b51de99c gcc compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 kernel signature: f1977bd610d47e8084d73d931c99ea5ee9998dead294f61c577b825234dad00e all runs: crashed: possible deadlock in snd_pcm_period_elapsed representative crash: possible deadlock in snd_pcm_period_elapsed, types: [LOCKDEP] # git bisect bad f5d9ddf1214bf878ca69c905c2f410c5b51de99c Bisecting: 162 revisions left to test after this (roughly 7 steps) [c06a7a8e885753a024163bbb0dfd7349e8054643] ASoC: dt-bindings: microchip: add sam9x7 testing commit c06a7a8e885753a024163bbb0dfd7349e8054643 gcc compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 kernel signature: 02b9a27bed18a18f1ae13369afe11cc7903ad058dd56e88a85699c544dd74a39 all runs: OK false negative chance: 0.000 # git bisect good c06a7a8e885753a024163bbb0dfd7349e8054643 Bisecting: 81 revisions left to test after this (roughly 6 steps) [d648843aa4742377b22e273c80d575e98195930f] ALSA: compress_offload: Use guard() for locking testing commit d648843aa4742377b22e273c80d575e98195930f gcc compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 kernel signature: 5d759630165343de5eba636d45d3c4f2ed3abbdf2879a9325be1db5eb43b3db1 all runs: OK false negative chance: 0.000 # git bisect good d648843aa4742377b22e273c80d575e98195930f Bisecting: 40 revisions left to test after this (roughly 5 steps) [5f51de7e30c7282162a631af8a425b54a4576346] ALSA: hda/tas2781: do not call pm_runtime_force_* in system_resume/suspend testing commit 5f51de7e30c7282162a631af8a425b54a4576346 gcc compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 kernel signature: 141d16da665e24e3fa3f2a5aee74f2a6068b3c3fee0296c1ee3486b90103df59 all runs: crashed: possible deadlock in snd_pcm_period_elapsed representative crash: possible deadlock in snd_pcm_period_elapsed, types: [LOCKDEP] # git bisect bad 5f51de7e30c7282162a631af8a425b54a4576346 Bisecting: 20 revisions left to test after this (roughly 4 steps) [650224fe8d5f6dbe6cc5875d14bf80da60dd56f8] ALSA: pcm: Use guard() for PCM stream locks testing commit 650224fe8d5f6dbe6cc5875d14bf80da60dd56f8 gcc compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 kernel signature: e4605dc907ec20eb326b0fb49ce50566b8a94a30660bb76af124bd51b9635d78 all runs: crashed: possible deadlock in snd_pcm_period_elapsed representative crash: possible deadlock in snd_pcm_period_elapsed, types: [LOCKDEP] # git bisect bad 650224fe8d5f6dbe6cc5875d14bf80da60dd56f8 Bisecting: 9 revisions left to test after this (roughly 3 steps) [68f014a58b6540847b0939a9a4023ed6eb834608] ALSA: seq: fifo: Use guard() for locking testing commit 68f014a58b6540847b0939a9a4023ed6eb834608 gcc compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 kernel signature: e7de4f19964daf494b74b2adcb443a036b0e2e6f133c010ba3e0e9fbae222ee6 all runs: crashed: possible deadlock in snd_pcm_period_elapsed representative crash: possible deadlock in snd_pcm_period_elapsed, types: [LOCKDEP] # git bisect bad 68f014a58b6540847b0939a9a4023ed6eb834608 Bisecting: 4 revisions left to test after this (roughly 2 steps) [2dc49651fca1e8ecd6c177cd9b576a26761a5cdf] ALSA: mixer_oss: Use guard() for locking testing commit 2dc49651fca1e8ecd6c177cd9b576a26761a5cdf gcc compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 kernel signature: fa46318063434b8f1c23fe51782c5c940cc96dc4b2f0d8a58e214c622e9b1b78 all runs: crashed: possible deadlock in snd_pcm_period_elapsed representative crash: possible deadlock in snd_pcm_period_elapsed, types: [LOCKDEP] # git bisect bad 2dc49651fca1e8ecd6c177cd9b576a26761a5cdf Bisecting: 2 revisions left to test after this (roughly 1 step) [b04892691d2659a592eaaa0444d60eb12cfa4df8] ALSA: hrtimer: Use guard() for locking testing commit b04892691d2659a592eaaa0444d60eb12cfa4df8 gcc compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 kernel signature: 05a8c31840f62408194d1e762a0b572871f9198b4045b8cbd426d98ac7285868 all runs: crashed: possible deadlock in snd_pcm_period_elapsed representative crash: possible deadlock in snd_pcm_period_elapsed, types: [LOCKDEP] # git bisect bad b04892691d2659a592eaaa0444d60eb12cfa4df8 Bisecting: 0 revisions left to test after this (roughly 0 steps) [beb45974dd49068b24788bbfc2abe20d50503761] ALSA: timer: Use guard() for locking testing commit beb45974dd49068b24788bbfc2abe20d50503761 gcc compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 kernel signature: 832b9d83b903032ebfa5382d694c3e68ea358ced5ef7c51f04c1086e8e50f54b all runs: crashed: possible deadlock in snd_pcm_period_elapsed representative crash: possible deadlock in snd_pcm_period_elapsed, types: [LOCKDEP] # git bisect bad beb45974dd49068b24788bbfc2abe20d50503761 beb45974dd49068b24788bbfc2abe20d50503761 is the first bad commit commit beb45974dd49068b24788bbfc2abe20d50503761 Author: Takashi Iwai Date: Tue Feb 27 09:52:45 2024 +0100 ALSA: timer: Use guard() for locking We can simplify the code gracefully with new guard() macro and co for automatic cleanup of locks. For making changes easier, some functions widen the application of register_mutex, but those shouldn't influence on any actual performance. Also, one code block was factored out as a function so that guard() can be applied cleanly without much indentation. There are still a few remaining explicit spin_lock/unlock calls, and those are for the places where we do temporary unlock/relock, which doesn't fit well with the guard(), so far. Only the code refactoring, and no functional changes. Signed-off-by: Takashi Iwai Link: https://lore.kernel.org/r/20240227085306.9764-4-tiwai@suse.de sound/core/timer.c | 429 +++++++++++++++++++--------------------------- sound/core/timer_compat.c | 7 +- 2 files changed, 177 insertions(+), 259 deletions(-) accumulated error probability: 0.00 culprit signature: 832b9d83b903032ebfa5382d694c3e68ea358ced5ef7c51f04c1086e8e50f54b parent signature: 5d759630165343de5eba636d45d3c4f2ed3abbdf2879a9325be1db5eb43b3db1 revisions tested: 21, total time: 3h57m3.665630199s (build: 1h53m39.506185332s, test: 1h54m41.568763453s) first bad commit: beb45974dd49068b24788bbfc2abe20d50503761 ALSA: timer: Use guard() for locking recipients (to): ["tiwai@suse.de"] recipients (cc): [] crash: possible deadlock in snd_pcm_period_elapsed ======================================================== WARNING: possible irq lock inversion dependency detected 6.8.0-rc2-syzkaller #0 Not tainted -------------------------------------------------------- swapper/0/0 just changed the state of lock: ffff8881033c3510 (&group->lock){..-.}-{2:2}, at: snd_pcm_period_elapsed+0x1a/0xa0 sound/core/pcm_lib.c:1907 but this lock took another, SOFTIRQ-unsafe lock in the past: (&timer->lock){+.+.}-{2:2} and interrupts could create inverse lock ordering between them. other info that might help us debug this: Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&timer->lock); local_irq_disable(); lock(&group->lock); lock(&timer->lock); lock(&group->lock); *** DEADLOCK *** no locks held by swapper/0/0. the shortest dependencies between 2nd lock and 1st lock: -> (&timer->lock){+.+.}-{2:2} { HARDIRQ-ON-W at: lock_acquire+0xea/0x270 kernel/locking/lockdep.c:5754 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:351 [inline] class_spinlock_constructor include/linux/spinlock.h:561 [inline] snd_timer_close_locked+0x2a/0x290 sound/core/timer.c:412 snd_timer_close+0x40/0x80 sound/core/timer.c:464 snd_seq_timer_close+0x43/0x60 sound/core/seq/seq_timer.c:326 queue_delete sound/core/seq/seq_queue.c:134 [inline] snd_seq_queue_delete+0xaf/0x120 sound/core/seq/seq_queue.c:196 delete_seq_queue sound/core/seq/oss/seq_oss_init.c:371 [inline] snd_seq_oss_release+0x88/0xd0 sound/core/seq/oss/seq_oss_init.c:416 odev_release+0x27/0x40 sound/core/seq/oss/seq_oss.c:144 __fput+0xf4/0x290 fs/file_table.c:376 __do_sys_close fs/open.c:1554 [inline] __se_sys_close+0x6a/0xc0 fs/open.c:1539 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xa7/0x190 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x6f/0x77 SOFTIRQ-ON-W at: lock_acquire+0xea/0x270 kernel/locking/lockdep.c:5754 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:351 [inline] class_spinlock_constructor include/linux/spinlock.h:561 [inline] snd_timer_close_locked+0x2a/0x290 sound/core/timer.c:412 snd_timer_close+0x40/0x80 sound/core/timer.c:464 snd_seq_timer_close+0x43/0x60 sound/core/seq/seq_timer.c:326 queue_delete sound/core/seq/seq_queue.c:134 [inline] snd_seq_queue_delete+0xaf/0x120 sound/core/seq/seq_queue.c:196 delete_seq_queue sound/core/seq/oss/seq_oss_init.c:371 [inline] snd_seq_oss_release+0x88/0xd0 sound/core/seq/oss/seq_oss_init.c:416 odev_release+0x27/0x40 sound/core/seq/oss/seq_oss.c:144 __fput+0xf4/0x290 fs/file_table.c:376 __do_sys_close fs/open.c:1554 [inline] __se_sys_close+0x6a/0xc0 fs/open.c:1539 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xa7/0x190 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x6f/0x77 INITIAL USE at: lock_acquire+0xea/0x270 kernel/locking/lockdep.c:5754 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x61/0xa0 kernel/locking/spinlock.c:162 class_spinlock_irqsave_constructor include/linux/spinlock.h:574 [inline] snd_timer_notify+0x5b/0x140 sound/core/timer.c:1040 snd_pcm_timer_notify sound/core/pcm_native.c:618 [inline] snd_pcm_post_stop+0x49/0x80 sound/core/pcm_native.c:1528 snd_pcm_action+0xcf/0x100 sound/core/pcm_native.c:1372 snd_pcm_stop sound/core/pcm_native.c:1551 [inline] snd_pcm_drop+0x7b/0xd0 sound/core/pcm_native.c:2231 snd_pcm_oss_sync+0xb2/0x420 sound/core/oss/pcm_oss.c:1735 snd_pcm_oss_release+0x44/0xe0 sound/core/oss/pcm_oss.c:2577 __fput+0xf4/0x290 fs/file_table.c:376 __do_sys_close fs/open.c:1554 [inline] __se_sys_close+0x6a/0xc0 fs/open.c:1539 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xa7/0x190 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x6f/0x77 } ... key at: [] snd_timer_new.__key+0x0/0x10 ... acquired at: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x61/0xa0 kernel/locking/spinlock.c:162 class_spinlock_irqsave_constructor include/linux/spinlock.h:574 [inline] snd_timer_notify+0x5b/0x140 sound/core/timer.c:1040 snd_pcm_timer_notify sound/core/pcm_native.c:618 [inline] snd_pcm_post_stop+0x49/0x80 sound/core/pcm_native.c:1528 snd_pcm_action+0xcf/0x100 sound/core/pcm_native.c:1372 snd_pcm_stop sound/core/pcm_native.c:1551 [inline] snd_pcm_drop+0x7b/0xd0 sound/core/pcm_native.c:2231 snd_pcm_oss_sync+0xb2/0x420 sound/core/oss/pcm_oss.c:1735 snd_pcm_oss_release+0x44/0xe0 sound/core/oss/pcm_oss.c:2577 __fput+0xf4/0x290 fs/file_table.c:376 __do_sys_close fs/open.c:1554 [inline] __se_sys_close+0x6a/0xc0 fs/open.c:1539 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xa7/0x190 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x6f/0x77 -> (&group->lock){..-.}-{2:2} { IN-SOFTIRQ-W at: lock_acquire+0xea/0x270 kernel/locking/lockdep.c:5754 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x61/0xa0 kernel/locking/spinlock.c:162 snd_pcm_period_elapsed+0x1a/0xa0 sound/core/pcm_lib.c:1907 dummy_hrtimer_callback+0x1a/0x50 sound/drivers/dummy.c:385 __run_hrtimer kernel/time/hrtimer.c:1688 [inline] __hrtimer_run_queues+0x1a6/0x330 kernel/time/hrtimer.c:1752 hrtimer_run_softirq+0xa4/0x180 kernel/time/hrtimer.c:1769 __do_softirq+0x149/0x3d1 kernel/softirq.c:553 invoke_softirq kernel/softirq.c:427 [inline] __irq_exit_rcu+0x6f/0x100 kernel/softirq.c:632 irq_exit_rcu+0x9/0x30 kernel/softirq.c:644 sysvec_apic_timer_interrupt+0x92/0xb0 arch/x86/kernel/apic/apic.c:1076 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:649 native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline] arch_safe_halt arch/x86/include/asm/irqflags.h:86 [inline] acpi_safe_halt+0x20/0x30 drivers/acpi/processor_idle.c:112 acpi_idle_enter+0xc1/0xe0 drivers/acpi/processor_idle.c:707 cpuidle_enter_state+0xff/0x260 drivers/cpuidle/cpuidle.c:267 cpuidle_enter+0x28/0x40 drivers/cpuidle/cpuidle.c:388 call_cpuidle kernel/sched/idle.c:134 [inline] cpuidle_idle_call kernel/sched/idle.c:215 [inline] do_idle+0x1c8/0x270 kernel/sched/idle.c:312 cpu_startup_entry+0x24/0x30 kernel/sched/idle.c:410 rest_init+0x1e5/0x1f0 init/main.c:730 arch_call_rest_init+0x9/0x10 init/main.c:827 start_kernel+0x314/0x330 init/main.c:1072 x86_64_start_reservations+0x2a/0x30 arch/x86/kernel/head64.c:555 x86_64_start_kernel+0x94/0xa0 arch/x86/kernel/head64.c:536 secondary_startup_64_no_verify+0x15f/0x16b INITIAL USE at: lock_acquire+0xea/0x270 kernel/locking/lockdep.c:5754 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline] _raw_spin_lock_irq+0x5c/0x90 kernel/locking/spinlock.c:170 spin_lock_irq include/linux/spinlock.h:376 [inline] snd_pcm_group_lock_irq sound/core/pcm_native.c:97 [inline] snd_pcm_stream_lock_irq sound/core/pcm_native.c:136 [inline] snd_pcm_hw_params+0xa7/0x7a0 sound/core/pcm_native.c:736 snd_pcm_oss_change_params_locked+0xbcc/0x1130 sound/core/oss/pcm_oss.c:965 snd_pcm_oss_change_params sound/core/oss/pcm_oss.c:1105 [inline] snd_pcm_oss_make_ready+0xac/0x110 sound/core/oss/pcm_oss.c:1164 snd_pcm_oss_sync+0x95/0x420 sound/core/oss/pcm_oss.c:1731 snd_pcm_oss_release+0x44/0xe0 sound/core/oss/pcm_oss.c:2577 __fput+0xf4/0x290 fs/file_table.c:376 __do_sys_close fs/open.c:1554 [inline] __se_sys_close+0x6a/0xc0 fs/open.c:1539 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xa7/0x190 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x6f/0x77 } ... key at: [] snd_pcm_group_init.__key+0x0/0x10 ... acquired at: mark_lock+0xe9/0x150 kernel/locking/lockdep.c:4678 __lock_acquire+0x4c5/0x2490 kernel/locking/lockdep.c:5091 lock_acquire+0xea/0x270 kernel/locking/lockdep.c:5754 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x61/0xa0 kernel/locking/spinlock.c:162 snd_pcm_period_elapsed+0x1a/0xa0 sound/core/pcm_lib.c:1907 dummy_hrtimer_callback+0x1a/0x50 sound/drivers/dummy.c:385 __run_hrtimer kernel/time/hrtimer.c:1688 [inline] __hrtimer_run_queues+0x1a6/0x330 kernel/time/hrtimer.c:1752 hrtimer_run_softirq+0xa4/0x180 kernel/time/hrtimer.c:1769 __do_softirq+0x149/0x3d1 kernel/softirq.c:553 invoke_softirq kernel/softirq.c:427 [inline] __irq_exit_rcu+0x6f/0x100 kernel/softirq.c:632 irq_exit_rcu+0x9/0x30 kernel/softirq.c:644 sysvec_apic_timer_interrupt+0x92/0xb0 arch/x86/kernel/apic/apic.c:1076 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:649 native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline] arch_safe_halt arch/x86/include/asm/irqflags.h:86 [inline] acpi_safe_halt+0x20/0x30 drivers/acpi/processor_idle.c:112 acpi_idle_enter+0xc1/0xe0 drivers/acpi/processor_idle.c:707 cpuidle_enter_state+0xff/0x260 drivers/cpuidle/cpuidle.c:267 cpuidle_enter+0x28/0x40 drivers/cpuidle/cpuidle.c:388 call_cpuidle kernel/sched/idle.c:134 [inline] cpuidle_idle_call kernel/sched/idle.c:215 [inline] do_idle+0x1c8/0x270 kernel/sched/idle.c:312 cpu_startup_entry+0x24/0x30 kernel/sched/idle.c:410 rest_init+0x1e5/0x1f0 init/main.c:730 arch_call_rest_init+0x9/0x10 init/main.c:827 start_kernel+0x314/0x330 init/main.c:1072 x86_64_start_reservations+0x2a/0x30 arch/x86/kernel/head64.c:555 x86_64_start_kernel+0x94/0xa0 arch/x86/kernel/head64.c:536 secondary_startup_64_no_verify+0x15f/0x16b stack backtrace: CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.8.0-rc2-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x8d/0xe0 lib/dump_stack.c:106 print_irq_inversion_bug+0x2c1/0x2d0 kernel/locking/lockdep.c:4080 mark_lock_irq+0x32b/0x500 kernel/locking/lockdep.c:4243 mark_lock+0xe9/0x150 kernel/locking/lockdep.c:4678 __lock_acquire+0x4c5/0x2490 kernel/locking/lockdep.c:5091 lock_acquire+0xea/0x270 kernel/locking/lockdep.c:5754 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x61/0xa0 kernel/locking/spinlock.c:162 snd_pcm_period_elapsed+0x1a/0xa0 sound/core/pcm_lib.c:1907 dummy_hrtimer_callback+0x1a/0x50 sound/drivers/dummy.c:385 __run_hrtimer kernel/time/hrtimer.c:1688 [inline] __hrtimer_run_queues+0x1a6/0x330 kernel/time/hrtimer.c:1752 hrtimer_run_softirq+0xa4/0x180 kernel/time/hrtimer.c:1769 __do_softirq+0x149/0x3d1 kernel/softirq.c:553 invoke_softirq kernel/softirq.c:427 [inline] __irq_exit_rcu+0x6f/0x100 kernel/softirq.c:632 irq_exit_rcu+0x9/0x30 kernel/softirq.c:644 sysvec_apic_timer_interrupt+0x92/0xb0 arch/x86/kernel/apic/apic.c:1076 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:649 RIP: 0010:native_irq_disable arch/x86/include/asm/irqflags.h:37 [inline] RIP: 0010:arch_local_irq_disable arch/x86/include/asm/irqflags.h:72 [inline] RIP: 0010:acpi_safe_halt+0x20/0x30 drivers/acpi/processor_idle.c:113 Code: 90 90 90 90 90 90 90 90 90 90 65 48 8b 05 18 c8 94 7d 48 f7 00 08 00 00 00 75 10 66 90 0f 00 2d 00 a6 45 00 f3 0f 1e fa fb f4 c3 cc cc cc cc 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 RSP: 0018:ffffffff83403e00 EFLAGS: 00000246 RAX: ffffffff83423780 RBX: ffff8881016fe064 RCX: ffff88813bc00000 RDX: 0000000000000001 RSI: ffff8881016fe000 RDI: ffff8881016fe064 RBP: ffff8881036b2800 R08: 0000000c2ac8663d R09: 00000000000000ff R10: 0000000000000003 R11: ffffffff826e0710 R12: 0000000000000001 R13: 0000000000000000 R14: 0000000000000001 R15: ffffffff83643cb0 acpi_idle_enter+0xc1/0xe0 drivers/acpi/processor_idle.c:707 cpuidle_enter_state+0xff/0x260 drivers/cpuidle/cpuidle.c:267 cpuidle_enter+0x28/0x40 drivers/cpuidle/cpuidle.c:388 call_cpuidle kernel/sched/idle.c:134 [inline] cpuidle_idle_call kernel/sched/idle.c:215 [inline] do_idle+0x1c8/0x270 kernel/sched/idle.c:312 cpu_startup_entry+0x24/0x30 kernel/sched/idle.c:410 rest_init+0x1e5/0x1f0 init/main.c:730 arch_call_rest_init+0x9/0x10 init/main.c:827 start_kernel+0x314/0x330 init/main.c:1072 x86_64_start_reservations+0x2a/0x30 arch/x86/kernel/head64.c:555 x86_64_start_kernel+0x94/0xa0 arch/x86/kernel/head64.c:536 secondary_startup_64_no_verify+0x15f/0x16b ---------------- Code disassembly (best guess): 0: 90 nop 1: 90 nop 2: 90 nop 3: 90 nop 4: 90 nop 5: 90 nop 6: 90 nop 7: 90 nop 8: 90 nop 9: 90 nop a: 65 48 8b 05 18 c8 94 mov %gs:0x7d94c818(%rip),%rax # 0x7d94c82a 11: 7d 12: 48 f7 00 08 00 00 00 testq $0x8,(%rax) 19: 75 10 jne 0x2b 1b: 66 90 xchg %ax,%ax 1d: 0f 00 2d 00 a6 45 00 verw 0x45a600(%rip) # 0x45a624 24: f3 0f 1e fa endbr64 28: fb sti 29: f4 hlt * 2a: fa cli <-- trapping instruction 2b: c3 ret 2c: cc int3 2d: cc int3 2e: cc int3 2f: cc int3 30: 66 2e 0f 1f 84 00 00 cs nopw 0x0(%rax,%rax,1) 37: 00 00 00 3a: 90 nop 3b: 90 nop 3c: 90 nop 3d: 90 nop 3e: 90 nop 3f: 90 nop