我正在尝试在 Inforce 6540 板上运行足够新的内核 (4.9)，这是一款配备 Qualcomm Snapdragon 805 的单板计算机（也称为 APQ8084，具有四个 Krait 450 核心的 SoC，ARMv7-A）。
系统启动，并在串行接口上打印跟踪信息，但无法运行 init。
启动init：/sbin/init存在但无法执行（错误-117）
错误代码也可能是-2，在这两种情况下对我来说都没有意义。
我还注意到 devtmpfs 无法挂载。 ext4 rootfs 被告知挂载成功。
通常的解释是：
- 内核缺乏 devtmpfs 支持。我检查了我的配置，devtmpfs 已启用。
- 文件系统已损坏。我用主板最初使用的旧自定义 3.10 内核替换了内核（和 devicetree），旧内核设法启动 init （指向 systemd 的链接，稍后停止，正如我们可能期望从为4.9 内核运行在 3.10 上）。 （内核和devicetree不在rootfs分区上，由u-boot加载）。
什么可以解释 init 无法运行？
以下是内核的整个引导跟踪。
[ 0.000000] Booting Linux on physical CPU 0x0
[ 0.000000] Linux version 4.9.56+linaro (Jacen@dev-computer) (gcc version 6.2.1 20161016 (Linaro GCC 6.2-2016.11) ) #1 SMP PREEMPT Wed Apr 18 12:05:02 CEST 2018
[ 0.000000] CPU: ARMv7 Processor [513f06f1] revision 1 (ARMv7), cr=10c5787d
[ 0.000000] CPU: div instructions available: patching division code
[ 0.000000] CPU: PIPT / VIPT nonaliasing data cache, PIPT instruction cache
[ 0.000000] OF: fdt:Machine model: Qualcomm APQ8084/IFC6540
[ 0.000000] Memory policy: Data cache writealloc
[ 0.000000] percpu: Embedded 15 pages/cpu @ee4b0000 s30796 r8192 d22452 u61440
[ 0.000000] Built 1 zonelists in Zone order, mobility grouping on. Total pages: 784192
[ 0.000000] Kernel command line: root=/dev/mmcblk0p25 rw rootwait console=ttyMSM0,115200n8 androidboot.bootdevice=msm_sdcc.1 androidboot.serialno=a06b8142 androidboot.baseband=apq mdss_mdp.panel=0:dsi:0:
[ 0.000000] PID hash table entries: 4096 (order: 2, 16384 bytes)
[ 0.000000] Dentry cache hash table entries: 131072 (order: 7, 524288 bytes)
[ 0.000000] Inode-cache hash table entries: 65536 (order: 6, 262144 bytes)
[ 0.000000] Memory: 3100492K/3143680K available (8192K kernel code, 734K rwdata, 3176K rodata, 1024K init, 359K bss, 43188K reserved, 0K cma-reserved, 2359296K highmem)
[ 0.000000] Virtual kernel memory layout:
[ 0.000000] vector : 0xffff0000 - 0xffff1000 ( 4 kB)
[ 0.000000] fixmap : 0xffc00000 - 0xfff00000 (3072 kB)
[ 0.000000] vmalloc : 0xf0800000 - 0xff800000 ( 240 MB)
[ 0.000000] lowmem : 0xc0000000 - 0xf0000000 ( 768 MB)
[ 0.000000] pkmap : 0xbfe00000 - 0xc0000000 ( 2 MB)
[ 0.000000] modules : 0xbf000000 - 0xbfe00000 ( 14 MB)
[ 0.000000] .text : 0xc0208000 - 0xc0b00000 (9184 kB)
[ 0.000000] .init : 0xc0f00000 - 0xc1000000 (1024 kB)
[ 0.000000] .data : 0xc1000000 - 0xc10b78a8 ( 735 kB)
[ 0.000000] .bss : 0xc10b9000 - 0xc1112cfc ( 360 kB)
[ 0.000000] SLUB: HWalign=64, Order=0-3, MinObjects=0, CPUs=4, Nodes=1
[ 0.000000] Preemptible hierarchical RCU implementation.
[ 0.000000] Build-time adjustment of leaf fanout to 32.
[ 0.000000] NR_IRQS:16 nr_irqs:16 16
[ 0.000000] arm_arch_timer: Architected cp15 and mmio timer(s) running at 19.20MHz (virt/virt).
[ 0.000000] clocksource: arch_sys_counter: mask: 0xffffffffffffff max_cycles: 0x46d987e47, max_idle_ns: 440795202767 ns
[ 0.000005] sched_clock: 56 bits at 19MHz, resolution 52ns, wraps every 4398046511078ns
[ 0.000018] Switching to timer-based delay loop, resolution 52ns
[ 0.000200] Console: colour dummy device 80x30
[ 0.000223] Calibrating delay loop (skipped), value calculated using timer frequency.. 38.40 BogoMIPS (lpj=192000)
[ 0.000238] pid_max: default: 32768 minimum: 301
[ 0.000363] Mount-cache hash table entries: 2048 (order: 1, 8192 bytes)
[ 0.000376] Mountpoint-cache hash table entries: 2048 (order: 1, 8192 bytes)
[ 0.001050] CPU: Testing write buffer coherency: ok
[ 0.001312] CPU0: thread -1, cpu 0, socket 0, mpidr 80000000
[ 0.001426] Setting up static identity map for 0x300000 - 0x300058
[ 0.200688] CPU1: thread -1, cpu 1, socket 0, mpidr 80000001
[ 0.280884] CPU2: thread -1, cpu 2, socket 0, mpidr 80000002
[ 0.361088] CPU3: thread -1, cpu 3, socket 0, mpidr 80000003
[ 0.361323] Brought up 4 CPUs
[ 0.361347] SMP: Total of 4 processors activated (153.60 BogoMIPS).
[ 0.361357] CPU: All CPU(s) started in SVC mode.
[ 0.363838] devtmpfs: initialized
[ 0.368946] VFP support v0.3: implementor 51 architecture 64 part 6f variant 3 rev 1
[ 0.369232] clocksource: jiffies: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 19112604462750000 ns
[ 0.369254] futex hash table entries: 1024 (order: 4, 65536 bytes)
[ 0.369431] pinctrl core: initialized pinctrl subsystem
[ 0.370514] NET: Registered protocol family 16
[ 0.370824] DMA: preallocated 256 KiB pool for atomic coherent allocations
[ 0.400854] cpuidle: using governor menu
[ 0.401142] hw-breakpoint: found 5 (+1 reserved) breakpoint and 4 watchpoint registers.
[ 0.401155] hw-breakpoint: maximum watchpoint size is 8 bytes.
[ 0.462767] vgaarb: loaded
[ 0.463148] SCSI subsystem initialized
[ 0.463639] usbcore: registered new interface driver usbfs
[ 0.463718] usbcore: registered new interface driver hub
[ 0.463830] usbcore: registered new device driver usb
[ 0.464664] Advanced Linux Sound Architecture Driver Initialized.
[ 0.466310] clocksource: Switched to clocksource arch_sys_counter
[ 0.533598] NET: Registered protocol family 2
[ 0.534156] TCP established hash table entries: 8192 (order: 3, 32768 bytes)
[ 0.534208] TCP bind hash table entries: 8192 (order: 4, 65536 bytes)
[ 0.534285] TCP: Hash tables configured (established 8192 bind 8192)
[ 0.534341] UDP hash table entries: 512 (order: 2, 16384 bytes)
[ 0.534365] UDP-Lite hash table entries: 512 (order: 2, 16384 bytes)
[ 0.534527] NET: Registered protocol family 1
[ 0.535079] RPC: Registered named UNIX socket transport module.
[ 0.535092] RPC: Registered udp transport module.
[ 0.535103] RPC: Registered tcp transport module.
[ 0.535112] RPC: Registered tcp NFSv4.1 backchannel transport module.
[ 0.535438] Trying to unpack rootfs image as initramfs...
[ 0.535787] rootfs image is not initramfs (junk in compressed archive); looks like an initrd
[ 0.535885] Freeing initrd memory: 4K
[ 0.536245] hw perfevents: enabled with armv7_krait PMU driver, 5 counters available
[ 0.538614] workingset: timestamp_bits=14 max_order=20 bucket_order=6
[ 0.548667] NFS: Registering the id_resolver key type
[ 0.548700] Key type id_resolver registered
[ 0.548712] Key type id_legacy registered
[ 0.549461] jffs2: version 2.2. (NAND) © 2001-2006 Red Hat, Inc.
[ 0.550229] fuse init (API version 7.26)
[ 0.553343] bounce: pool size: 64 pages
[ 0.553401] Block layer SCSI generic (bsg) driver version 0.4 loaded (major 252)
[ 0.553575] io scheduler noop registered
[ 0.553588] io scheduler deadline registered
[ 0.553779] io scheduler cfq registered (default)
[ 0.557749] msm_serial f995e000.serial: msm_serial: detected port #0
[ 0.557803] msm_serial f995e000.serial: uartclk = 7372800
[ 0.557852] f995e000.serial: ttyMSM0 at MMIO 0xf995e000 (irq = 170, base_baud = 460800) is a MSM
[ 0.557898] msm_serial: console setup on port #0
[ 1.127057] console [ttyMSM0] enabled
[ 1.132017] msm_serial: driver initialized
[ 1.135541] [drm] Initialized
[ 1.155600] brd: module loaded
[ 1.164058] loop: module loaded
[ 1.164452] SCSI Media Changer driver v0.25
[ 1.166910] spmi spmi-0: PMIC Arb Version-1 (0x20000002)
[ 1.180872] libphy: Fixed MDIO Bus: probed
[ 1.181013] SLIP: version 0.8.4-NET3.019-NEWTTY (dynamic channels, max=256) (6 bit encapsulation enabled).
[ 1.183860] CSLIP: code copyright 1989 Regents of the University of California.
[ 1.193649] usbcore: registered new interface driver ax88179_178a
[ 1.200800] usbcore: registered new interface driver cdc_ether
[ 1.207063] usbcore: registered new interface driver net1080
[ 1.212726] usbcore: registered new interface driver cdc_subset
[ 1.218601] usbcore: registered new interface driver cdc_ncm
[ 1.224574] ehci_hcd: USB 2.0 'Enhanced' Host Controller (EHCI) Driver
[ 1.230083] ehci-pci: EHCI PCI platform driver
[ 1.236461] ehci-msm: Qualcomm On-Chip EHCI Host Controller
[ 1.241038] usbcore: registered new interface driver usbserial
[ 1.246351] usbcore: registered new interface driver usbserial_generic
[ 1.252217] usbserial: USB Serial support registered for generic
[ 1.260079] mousedev: PS/2 mouse device common for all mice
[ 1.265667] input: pm8941_pwrkey as /devices/platform/soc/fc4cf000.spmi/spmi-0/0-00/fc4cf000.spmi:pma8084@0:pwrkey@800/input/input0
[ 1.271688] rtc-pm8xxx fc4cf000.spmi:pma8084@0:rtc@6000: rtc core: registered pm8xxx_rtc as rtc0
[ 1.282117] i2c /dev entries driver
[ 1.291579] cpuidle: enable-method property 'qcom,kpss-acc-v2' found operations
[ 1.294356] cpuidle: enable-method property 'qcom,kpss-acc-v2' found operations
[ 1.301643] cpuidle: enable-method property 'qcom,kpss-acc-v2' found operations
[ 1.308978] cpuidle: enable-method property 'qcom,kpss-acc-v2' found operations
[ 1.316569] sdhci: Secure Digital Host Controller Interface driver
[ 1.323352] sdhci: Copyright(c) Pierre Ossman
[ 1.329630] sdhci-pltfm: SDHCI platform and OF driver helper
[ 1.406676] mmc0: SDHCI controller on f9824900.sdhci [f9824900.sdhci] using ADMA 64-bit
[ 1.417000] ledtrig-cpu: registered to indicate activity on CPUs
[ 1.419371] usbcore: registered new interface driver usbhid
[ 1.424119] usbhid: USB HID core driver
[ 1.431805] usbcore: registered new interface driver snd-usb-audio
[ 1.444474] oprofile: using timer interrupt.
[ 1.445341] NET: Registered protocol family 10
[ 1.449328] sit: IPv6, IPv4 and MPLS over IPv4 tunneling driver
[ 1.452812] NET: Registered protocol family 17
[ 1.458042] Key type dns_resolver registered
[ 1.462550] Registering SWP/SWPB emulation handler
[ 1.490444] mmc0: new HS200 MMC card at address 0001
[ 1.491390] mmcblk0: mmc0:0001 SEM16G 14.7 GiB
[ 1.495108] mmcblk0boot0: mmc0:0001 SEM16G partition 1 4.00 MiB
[ 1.504668] mmcblk0boot1: mmc0:0001 SEM16G partition 2 4.00 MiB
[ 1.505261] mmcblk0rpmb: mmc0:0001 SEM16G partition 3 4.00 MiB
[ 1.511106] rtc-pm8xxx fc4cf000.spmi:pma8084@0:rtc@6000: setting system clock to 1970-01-01 00:00:03 UTC (3)
[ 1.517337] ALSA device list:
[ 1.526473] No soundcards found.
[ 1.527644] Alternate GPT is invalid, using primary �
[ 1.539212] RAMDISK: Couldn't find valid RAM disk image starting at 0.
[ 1.540325] EXT4-fs (mmcblk0p25): couldn't mount as ext3 due to feature incompatibilities
[ 1.554971] mmcblk0: error -110 sending stop command, original cmd response 0x900, card status 0x400900
[ 1.584967] EXT4-fs (mmcblk0p25): recovery complete
[ 1.585980] EXT4-fs (mmcblk0p25): mounted filesystem with ordered data mode. Opts: (null)
[ 1.588779] VFS: Mounted root (ext4 filesystem) on device 179:25.
[ 1.597953] devtmpfs: error mounting -2
[ 1.605619] Freeing unused kernel memory: 1024K
[ 1.611168] random: fast init done
[ 1.613665] EXT4-fs error (device mmcblk0p25): ext4_lookup:1611: inode #2852: comm swapper/0: deleted inode referenced: 2952
[ 1.615789] Starting init: /sbin/init exists but couldn't execute it (error -117)
[ 1.631371] EXT4-fs error (device mmcblk0p25): ext4_lookup:1611: inode #2852: comm swapper/0: deleted inode referenced: 2952
[ 1.634427] Starting init: /bin/sh exists but couldn't execute it (error -117)
[ 1.644861] Kernel panic - not syncing: No working init found. Try passing init= option to kernel. See Linux Documentation/init.txt for guidance.
[ 1.651777] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.9.56+linaro #1
[ 1.664870] Hardware name: Generic DT based system
[ 1.671400] [<c0310518>] (unwind_backtrace) from [<c030c684>] (show_stack+0x10/0x14)
[ 1.676166] [<c030c684>] (show_stack) from [<c061b97c>] (dump_stack+0x78/0x8c)
[ 1.684067] [<c061b97c>] (dump_stack) from [<c03edb40>] (panic+0xdc/0x250)
[ 1.691098] [<c03edb40>] (panic) from [<c0a4611c>] (kernel_init+0x104/0x114)
[ 1.697958] [<c0a4611c>] (kernel_init) from [<c03083b8>] (ret_from_fork+0x14/0x3c)
[ 1.705167] CPU1: stopping
[ 1.712535] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.9.56+linaro #1
[ 1.715220] Hardware name: Generic DT based system
[ 1.721754] [<c0310518>] (unwind_backtrace) from [<c030c684>] (show_stack+0x10/0x14)
[ 1.726525] [<c030c684>] (show_stack) from [<c061b97c>] (dump_stack+0x78/0x8c)
[ 1.734422] [<c061b97c>] (dump_stack) from [<c030f5b8>] (handle_IPI+0x34c/0x360)
[ 1.741452] [<c030f5b8>] (handle_IPI) from [<c03014a8>] (gic_handle_irq+0x88/0x8c)
[ 1.749011] [<c03014a8>] (gic_handle_irq) from [<c0a4bc4c>] (__irq_svc+0x6c/0xa8)
[ 1.756371] Exception stack(0xedce3f58 to 0xedce3fa0)
[ 1.763929] 3f40: 00000001 c0d2bda8
[ 1.768991] 3f60: 00000001 00000000 c1088754 c10a7a98 00000000 c1003098 65a28bb2 00000000
[ 1.777149] 3f80: 00000000 ed535c00 0682aaab edce3fa8 c0363868 c0840534 60000013 ffffffff
[ 1.785300] [<c0a4bc4c>] (__irq_svc) from [<c0840534>] (cpuidle_enter_state+0x154/0x428)
[ 1.793458] [<c0840534>] (cpuidle_enter_state) from [<c0363a90>] (cpu_startup_entry+0x148/0x218)
[ 1.801613] [<c0363a90>] (cpu_startup_entry) from [<0030154c>] (0x30154c)
[ 1.810366] CPU3: stopping
[ 1.817047] CPU: 3 PID: 0 Comm: swapper/3 Not tainted 4.9.56+linaro #1
[ 1.819648] Hardware name: Generic DT based system
[ 1.826181] [<c0310518>] (unwind_backtrace) from [<c030c684>] (show_stack+0x10/0x14)
[ 1.830951] [<c030c684>] (show_stack) from [<c061b97c>] (dump_stack+0x78/0x8c)
[ 1.838852] [<c061b97c>] (dump_stack) from [<c030f5b8>] (handle_IPI+0x34c/0x360)
[ 1.845878] [<c030f5b8>] (handle_IPI) from [<c03014a8>] (gic_handle_irq+0x88/0x8c)
[ 1.853434] [<c03014a8>] (gic_handle_irq) from [<c0a4bc4c>] (__irq_svc+0x6c/0xa8)
[ 1.860798] Exception stack(0xedce7f58 to 0xedce7fa0)
[ 1.868352] 7f40: 00000003 c0d2bda8
[ 1.873417] 7f60: 00000001 00000000 c10887a4 c10a7a98 00000001 c1003098 65a41b46 00000000
[ 1.881577] 7f80: 00000001 ed574000 0682aaab edce7fa8 c0363868 c0840534 60000013 ffffffff
[ 1.889725] [<c0a4bc4c>] (__irq_svc) from [<c0840534>] (cpuidle_enter_state+0x154/0x428)
[ 1.897879] [<c0840534>] (cpuidle_enter_state) from [<c0363a90>] (cpu_startup_entry+0x148/0x218)
[ 1.906035] [<c0363a90>] (cpu_startup_entry) from [<0030154c>] (0x30154c)
[ 1.914792] CPU2: stopping
[ 1.921471] CPU: 2 PID: 0 Comm: swapper/2 Not tainted 4.9.56+linaro #1
[ 1.924074] Hardware name: Generic DT based system
[ 1.930606] [<c0310518>] (unwind_backtrace) from [<c030c684>] (show_stack+0x10/0x14)
[ 1.935379] [<c030c684>] (show_stack) from [<c061b97c>] (dump_stack+0x78/0x8c)
[ 1.943277] [<c061b97c>] (dump_stack) from [<c030f5b8>] (handle_IPI+0x34c/0x360)
[ 1.950306] [<c030f5b8>] (handle_IPI) from [<c03014a8>] (gic_handle_irq+0x88/0x8c)
[ 1.957862] [<c03014a8>] (gic_handle_irq) from [<c0a4bc4c>] (__irq_svc+0x6c/0xa8)
[ 1.965224] Exception stack(0xedce5f58 to 0xedce5fa0)
[ 1.972780] 5f40: 00000002 c0d2bda8
[ 1.977843] 5f60: 00000001 00000000 c10887a4 c10a7a98 00000001 c1003098 65a5403e 00000000
[ 1.986003] 5f80: 00000001 ed535e00 0682aaab edce5fa8 c0363868 c0840534 60000013 ffffffff
[ 1.994149] [<c0a4bc4c>] (__irq_svc) from [<c0840534>] (cpuidle_enter_state+0x154/0x428)
[ 2.002307] [<c0840534>] (cpuidle_enter_state) from [<c0363a90>] (cpu_startup_entry+0x148/0x218)
[ 2.010464] [<c0363a90>] (cpu_startup_entry) from [<0030154c>] (0x30154c)
[ 2.019227] ---[ end Kernel panic - not syncing: No working init found. Try passing init= option to kernel. See Linux Documentation/init.txt for guidance.
答案1
我要感谢那些可能在我的问题上花费时间的人，事实证明问题中的信息无法找到正确的根本原因：
在其他一些启动上，devtmpfs正确挂载，并且init被杀死而不是不被执行，并且有一些痕迹，例如
[1.606597] mmcblk0：错误-110发送停止命令，原始cmd响应0x900，卡状态0x400900
[1.636655]内核恐慌 - 不同步：试图杀死init！退出代码=0x0000000b
我预计 ext4 rootfs 是正常的，但 eMMC 驱动程序会出现故障。
编辑：sdhci 驱动程序无法准确确定它可以使用的最高时钟速率。我将其固定为 200MHz，现在我的系统可以正确启动。