Hi, Starting with 4.6-rc1, a sleep 1 doesn't return :
execve("/bin/sleep", ["sleep", "1"], ["USER=root", "SHLVL=1", "OLDPWD=/var", "HOME=/", "TERM=vt102", "PATH=/sbin:/usr/sbin:/bin:/usr/bin", "SHELL=/bin/sh", "PWD=/"]) = 0 uname({sysname="Linux", nodename="LNS", release="4.5.0-09406-g46e595a17dcf", version="#72 Tue May 10 15:41:34 CEST 2016", machine="armv5tejl", domainname="(none)"}) = 0 brk(0) = 0x153000 brk(0x153d20) = 0x153d20 set_tls(0x1534c0, 0x14d1e4, 0, 0x153d20, 0x14e368) = 0 readlink("/proc/self/exe", "/bin/busybox", 4096) = 12 brk(0x174d20) = 0x174d20 brk(0x175000) = 0x175000 getuid32() = 0 rt_sigprocmask(SIG_BLOCK, [CHLD], [], 8) = 0 rt_sigaction(SIGCHLD, NULL, {SIG_DFL, [], 0}, 8) = 0 rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0 nanosleep({1, 0}, And the heartbeat led doesn't blink anymore (full on), as if the timers never fire. The platform is an AT91SAM9G35-CM. git bisect gives a merge as the 1st bad commit :( first bad commit: [46e595a17dcf11404f713845ecb5b06b92a94e43] Merge tag 'armsoc-drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc Here is the git bisect log: git bisect start # good: [b562e44f507e863c6792946e4e1b1449fbbac85d] Linux 4.5 git bisect good b562e44f507e863c6792946e4e1b1449fbbac85d # bad: [f55532a0c0b8bb6148f4e07853b876ef73bc69ca] Linux 4.6-rc1 git bisect bad f55532a0c0b8bb6148f4e07853b876ef73bc69ca # good: [6b5f04b6cf8ebab9a65d9c0026c650bb2538fd0f] Merge branch 'for-4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup git bisect good 6b5f04b6cf8ebab9a65d9c0026c650bb2538fd0f # bad: [53d2e6976bd4042672ed7b90dfbf4b31635b7dcf] Merge tag 'xfs-for-linus-4.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs git bisect bad 53d2e6976bd4042672ed7b90dfbf4b31635b7dcf # good: [8626c56c8279b88b91b8df55345cdf89542d5e90] bridge: fix potential use-after-free when hook returns QUEUE or STOLEN verdict git bisect good 8626c56c8279b88b91b8df55345cdf89542d5e90 # good: [8c6d4082fc6ad2214e945b5b7368b828fb16e9a9] Merge tag 'armsoc-arm64' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc git bisect good 8c6d4082fc6ad2214e945b5b7368b828fb16e9a9 # good: [915c56bc01d6eab071e0dd1c6ea3bf73fbe5124f] Merge tag 'armsoc-dt64' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc git bisect good 915c56bc01d6eab071e0dd1c6ea3bf73fbe5124f # bad: [24b5e20f11a75866bbffc46c30a22fa50612a769] Merge branch 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip git bisect bad 24b5e20f11a75866bbffc46c30a22fa50612a769 # bad: [46e595a17dcf11404f713845ecb5b06b92a94e43] Merge tag 'armsoc-drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc git bisect bad 46e595a17dcf11404f713845ecb5b06b92a94e43 # good: [4a6f791c359a78535553ccf060615622d27b1ce1] Merge tag 'omap-for-v4.6/defconfig-signed' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap into next/defconfig git bisect good 4a6f791c359a78535553ccf060615622d27b1ce1 # good: [f628c64fc0ffdcd08f39d74ec23ed7706cb8653b] Merge tag 'at91-ab-4.6-drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux into next/drivers git bisect good f628c64fc0ffdcd08f39d74ec23ed7706cb8653b # good: [387eb3f3d574ebf43b3afe83da59a99481866b78] reset: socfpga: Make reset_control_ops const git bisect good 387eb3f3d574ebf43b3afe83da59a99481866b78 # good: [87023bc2ed11ea6b0944b34cc0281454c01832bf] Merge tag 'sunxi-drivers-for-4.6' of https://git.kernel.org/pub/scm/linux/kernel/git/mripard/linux into next/drivers git bisect good 87023bc2ed11ea6b0944b34cc0281454c01832bf # good: [33b96d2c9579213cf3f36d7b29841b1e464750c4] bus: imx-weim: Take the 'status' property value into account git bisect good 33b96d2c9579213cf3f36d7b29841b1e464750c4 # good: [9fe5bf92c30a89631eb1fafe0d9b18e2ba331ebb] ARM: configs: Add new config fragment to change RAM start point git bisect good 9fe5bf92c30a89631eb1fafe0d9b18e2ba331ebb # good: [e3b1f64e04f57198ca0ab1216d824a5547be8446] Merge tag 'armsoc-defconfig' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc git bisect good e3b1f64e04f57198ca0ab1216d824a5547be8446 # first bad commit: [46e595a17dcf11404f713845ecb5b06b92a94e43] Merge tag 'armsoc-drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc And the defconfig : CONFIG_KERNEL_LZO=y CONFIG_DEFAULT_HOSTNAME="lns" # CONFIG_SWAP is not set CONFIG_SYSVIPC=y # CONFIG_CROSS_MEMORY_ATTACH is not set CONFIG_FHANDLE=y CONFIG_IKCONFIG=y CONFIG_IKCONFIG_PROC=y CONFIG_RELAY=y CONFIG_CC_OPTIMIZE_FOR_SIZE=y CONFIG_KALLSYMS_ALL=y CONFIG_EMBEDDED=y CONFIG_SLAB=y CONFIG_PARTITION_ADVANCED=y # CONFIG_IOSCHED_DEADLINE is not set # CONFIG_IOSCHED_CFQ is not set # CONFIG_ARCH_MULTI_V7 is not set CONFIG_ARCH_AT91=y CONFIG_SOC_AT91SAM9=y CONFIG_AEABI=y # CONFIG_COMPACTION is not set CONFIG_UACCESS_WITH_MEMCPY=y # CONFIG_ATAGS is not set CONFIG_ZBOOT_ROM_TEXT=0x0 CONFIG_ZBOOT_ROM_BSS=0x0 # CONFIG_COREDUMP is not set # CONFIG_SUSPEND is not set CONFIG_NET=y CONFIG_PACKET=y CONFIG_PACKET_DIAG=y CONFIG_UNIX=y CONFIG_UNIX_DIAG=y CONFIG_XFRM_USER=y CONFIG_NET_KEY=y CONFIG_INET=y CONFIG_IP_ADVANCED_ROUTER=y CONFIG_IP_MULTIPLE_TABLES=y CONFIG_IP_ROUTE_VERBOSE=y CONFIG_IP_PNP=y CONFIG_IP_PNP_DHCP=y CONFIG_INET_AH=y CONFIG_INET_ESP=y CONFIG_INET_IPCOMP=y CONFIG_INET_UDP_DIAG=y CONFIG_INET6_AH=y CONFIG_INET6_ESP=y CONFIG_INET6_IPCOMP=y CONFIG_NETFILTER=y # CONFIG_BRIDGE_NETFILTER is not set CONFIG_NETFILTER_NETLINK_LOG=y CONFIG_NF_CONNTRACK=y # CONFIG_NF_CONNTRACK_PROCFS is not set CONFIG_NF_CT_NETLINK=y CONFIG_NETFILTER_XT_TARGET_CONNMARK=y CONFIG_NETFILTER_XT_TARGET_MARK=y CONFIG_NF_CONNTRACK_IPV4=y CONFIG_NF_NAT_IPV4=y CONFIG_IP_NF_IPTABLES=y CONFIG_IP_NF_FILTER=y CONFIG_IP_NF_TARGET_REJECT=y CONFIG_IP_NF_MANGLE=y CONFIG_NF_CONNTRACK_IPV6=y CONFIG_IP6_NF_IPTABLES=y CONFIG_IP6_NF_MATCH_IPV6HEADER=y CONFIG_IP6_NF_FILTER=y CONFIG_IP6_NF_TARGET_REJECT=y CONFIG_IP6_NF_MANGLE=y CONFIG_BRIDGE=y # CONFIG_BRIDGE_IGMP_SNOOPING is not set CONFIG_DNS_RESOLVER=y CONFIG_NETLINK_DIAG=y CONFIG_CFG80211=y CONFIG_CFG80211_WEXT=y CONFIG_MAC80211=y CONFIG_MAC80211_LEDS=y CONFIG_RFKILL=y CONFIG_RFKILL_INPUT=y CONFIG_RFKILL_GPIO=y CONFIG_UEVENT_HELPER_PATH="/sbin/hotplug" CONFIG_DEVTMPFS=y CONFIG_DEVTMPFS_MOUNT=y # CONFIG_STANDALONE is not set # CONFIG_PREVENT_FIRMWARE_BUILD is not set # CONFIG_FIRMWARE_IN_KERNEL is not set CONFIG_MTD=y CONFIG_MTD_CMDLINE_PARTS=y CONFIG_MTD_NAND=y CONFIG_MTD_NAND_ATMEL=y CONFIG_MTD_UBI=y CONFIG_MTD_UBI_FASTMAP=y CONFIG_BLK_DEV_LOOP=y CONFIG_BLK_DEV_RAM=y CONFIG_BLK_DEV_RAM_COUNT=4 CONFIG_BLK_DEV_RAM_SIZE=8192 CONFIG_ATMEL_TCLIB=y CONFIG_ATMEL_SSC=y CONFIG_EEPROM_AT24=y CONFIG_EEPROM_93CX6=y CONFIG_SCSI=y CONFIG_BLK_DEV_SD=y # CONFIG_SCSI_LOWLEVEL is not set CONFIG_NETDEVICES=y # CONFIG_NET_VENDOR_ARC is not set # CONFIG_NET_CADENCE is not set # CONFIG_NET_VENDOR_BROADCOM is not set # CONFIG_NET_VENDOR_CIRRUS is not set # CONFIG_NET_VENDOR_EZCHIP is not set # CONFIG_NET_VENDOR_FARADAY is not set # CONFIG_NET_VENDOR_HISILICON is not set # CONFIG_NET_VENDOR_INTEL is not set # CONFIG_NET_VENDOR_MARVELL is not set # CONFIG_NET_VENDOR_MICREL is not set # CONFIG_NET_VENDOR_MICROCHIP is not set # CONFIG_NET_VENDOR_NATSEMI is not set # CONFIG_NET_VENDOR_NETRONOME is not set # CONFIG_NET_VENDOR_QUALCOMM is not set # CONFIG_NET_VENDOR_RENESAS is not set # CONFIG_NET_VENDOR_ROCKER is not set # CONFIG_NET_VENDOR_SAMSUNG is not set # CONFIG_NET_VENDOR_SEEQ is not set # CONFIG_NET_VENDOR_SMSC is not set # CONFIG_NET_VENDOR_STMICRO is not set # CONFIG_NET_VENDOR_SYNOPSYS is not set # CONFIG_NET_VENDOR_VIA is not set # CONFIG_NET_VENDOR_WIZNET is not set CONFIG_PHYLIB=y CONFIG_DAVICOM_PHY=y CONFIG_PPP=y CONFIG_PPP_DEFLATE=y CONFIG_PPP_ASYNC=y # CONFIG_USB_NET_DRIVERS is not set # CONFIG_WLAN is not set # CONFIG_INPUT_MOUSEDEV is not set CONFIG_INPUT_EVDEV=y # CONFIG_INPUT_KEYBOARD is not set # CONFIG_INPUT_MOUSE is not set CONFIG_INPUT_MISC=y CONFIG_INPUT_UINPUT=y # CONFIG_SERIO is not set # CONFIG_LEGACY_PTYS is not set # CONFIG_DEVKMEM is not set CONFIG_SERIAL_ATMEL=y CONFIG_SERIAL_ATMEL_CONSOLE=y # CONFIG_SERIAL_ATMEL_PDC is not set CONFIG_I2C=y # CONFIG_I2C_COMPAT is not set CONFIG_I2C_CHARDEV=y CONFIG_I2C_MUX=y CONFIG_I2C_AT91=y CONFIG_I2C_GPIO=y CONFIG_SPI=y CONFIG_SPI_ATMEL=y CONFIG_SPI_SPIDEV=y CONFIG_GPIO_SYSFS=y # CONFIG_HWMON is not set CONFIG_WATCHDOG=y CONFIG_AT91SAM9X_WATCHDOG=y CONFIG_SSB=y CONFIG_BCMA=y CONFIG_SOUND=y CONFIG_SND=y # CONFIG_SND_SUPPORT_OLD_API is not set # CONFIG_SND_VERBOSE_PROCFS is not set # CONFIG_SND_DRIVERS is not set # CONFIG_SND_ARM is not set # CONFIG_SND_SPI is not set # CONFIG_SND_USB is not set CONFIG_SND_SOC=y CONFIG_SND_ATMEL_SOC=y CONFIG_SND_AT91_SOC_SAM9X5_WM8731=y CONFIG_HIDRAW=y CONFIG_UHID=y CONFIG_USB_HIDDEV=y CONFIG_USB=y CONFIG_USB_ANNOUNCE_NEW_DEVICES=y CONFIG_USB_EHCI_HCD=y CONFIG_USB_EHCI_ROOT_HUB_TT=y CONFIG_USB_ACM=y CONFIG_USB_WDM=y CONFIG_USB_STORAGE=y CONFIG_USB_STORAGE_REALTEK=y CONFIG_USB_STORAGE_DATAFAB=y CONFIG_USB_STORAGE_FREECOM=y CONFIG_USB_STORAGE_ISD200=y CONFIG_USB_STORAGE_USBAT=y CONFIG_USB_STORAGE_SDDR09=y CONFIG_USB_STORAGE_SDDR55=y CONFIG_USB_STORAGE_JUMPSHOT=y CONFIG_USB_STORAGE_ALAUDA=y CONFIG_USB_STORAGE_ONETOUCH=y CONFIG_USB_STORAGE_KARMA=y CONFIG_USB_STORAGE_CYPRESS_ATACB=y CONFIG_USB_STORAGE_ENE_UB6250=y CONFIG_USB_SERIAL=y CONFIG_USB_SERIAL_IPW=y CONFIG_USB_SERIAL_PL2303=y CONFIG_USB_SERIAL_QUALCOMM=y CONFIG_USB_SERIAL_SIERRAWIRELESS=y CONFIG_USB_SERIAL_OPTION=y CONFIG_USB_EZUSB_FX2=y CONFIG_USB_GADGET=y CONFIG_USB_AT91=y CONFIG_USB_ATMEL_USBA=y CONFIG_USB_ETH=y CONFIG_NEW_LEDS=y CONFIG_LEDS_CLASS=y CONFIG_LEDS_GPIO=y CONFIG_LEDS_TRIGGER_TIMER=y CONFIG_LEDS_TRIGGER_ONESHOT=y CONFIG_LEDS_TRIGGER_HEARTBEAT=y CONFIG_LEDS_TRIGGER_GPIO=y CONFIG_LEDS_TRIGGER_DEFAULT_ON=y CONFIG_DMADEVICES=y CONFIG_AT_HDMAC=y # CONFIG_IOMMU_SUPPORT is not set CONFIG_FANOTIFY=y CONFIG_VFAT_FS=y CONFIG_FAT_DEFAULT_CODEPAGE=850 CONFIG_NTFS_FS=y CONFIG_TMPFS=y CONFIG_UBIFS_FS=y CONFIG_UBIFS_FS_ADVANCED_COMPR=y # CONFIG_NETWORK_FILESYSTEMS is not set CONFIG_NLS_DEFAULT="utf8" CONFIG_NLS_CODEPAGE_437=y CONFIG_NLS_CODEPAGE_850=y CONFIG_NLS_ISO8859_1=y CONFIG_NLS_UTF8=y CONFIG_PRINTK_TIME=y CONFIG_MESSAGE_LOGLEVEL_DEFAULT=7 CONFIG_STRIP_ASM_SYMS=y CONFIG_DEBUG_SECTION_MISMATCH=y CONFIG_MAGIC_SYSRQ=y CONFIG_LOCKUP_DETECTOR=y CONFIG_BOOTPARAM_SOFTLOCKUP_PANIC=y CONFIG_BOOTPARAM_HUNG_TASK_PANIC=y # CONFIG_SCHED_DEBUG is not set # CONFIG_DEBUG_BUGVERBOSE is not set CONFIG_FUNCTION_TRACER=y CONFIG_FTRACE_SYSCALLS=y CONFIG_TRACER_SNAPSHOT=y CONFIG_KEYS=y CONFIG_CRYPTO_ECB=y CONFIG_CRYPTO_CRC32C=y CONFIG_CRYPTO_MICHAEL_MIC=y CONFIG_CRYPTO_USER_API_HASH=y CONFIG_CRYPTO_USER_API_SKCIPHER=y # CONFIG_CRYPTO_HW is not set CONFIG_CRC_ITU_T=y CONFIG_CRC7=y Regards, Richard.