u-boot:即使内核小于最大BOOTM_LEN，也无法引导linux内核 [英] u-boot: cannot boot linux kernel despite kernel being less than maximum BOOTM_LEN
问题描述
我有一个带有u-boot的MIPS系统(VSC7427)，我正在尝试引导一个比供应商在其GPL版本中提供的内核更新的内核(该内核
I have a MIPS system (VSC7427) with u-boot and I am trying to boot a more recent kernel than the kernel provided by the vendor in their GPL release (which boots just fine).
内核FIT映像似乎是健全的，从输出来看，我认为它应该是可引导的:
The kernel FIT image appears to be sane, and judging by the output I think it should be bootable:
U-Boot 2019.10 (Mar 28 2021 - 20:41:55 +0000)
MSCC VCore-III MIPS 24Kec
Model: Cisco Meraki MS220-8P
DRAM: 128 MiB
Loading Environment from SPI Flash... SF: Detected mx25l12805d with page size 256 Bytes, erase size 64 KiB, total 16 MiB
OK
In: serial@10100000
Out: serial@10100000
Err: serial@10100000
Net:
Warning: switch@1010000 (eth0) using random MAC address - b2:6b:53:af:2d:a0
eth0: switch@1010000
luton # dhcp
(snipped)
luton # tftp vmlinux.gz.itb
Using switch@1010000 device
TFTP from server 192.168.1.60; our IP address is 192.168.1.154
Filename 'vmlinux.gz.itb'.
Load address: 0x80100000
Loading: #################################################################
(snipped)
done
Bytes transferred = 5172244 (4eec14 hex)
luton # iminfo 0x80100000
## Checking Image at 80100000 ...
FIT image found
FIT description: Linux 5.11.11
Image 0 (kernel@0)
Description: Linux 5.11.11
Type: Kernel Image
Compression: gzip compressed
Data Start: 0x801000c0
Data Size: 5167511 Bytes = 4.9 MiB
Architecture: MIPS
OS: Linux
Load Address: 0x80100000
Entry Point: 0x809898f4
Hash algo: sha1
Hash value: b963ed48f45e332bd5df263dd69d69c3818e6586
Image 1 (fdt@luton_pcb091)
Description: MSCC Luton PCB091 Device Tree
Type: Flat Device Tree
Compression: uncompressed
Data Start: 0x805edb60
Data Size: 2851 Bytes = 2.8 KiB
Architecture: MIPS
Hash algo: sha1
Hash value: 5283ae4322294e594a7be5e6de65e4f039ff36a5
Default Configuration: 'conf@default'
Configuration 0 (conf@default)
Description: Generic Linux kernel
Kernel: kernel@0
Configuration 1 (pcb091)
Description: Luton Linux kernel
Kernel: kernel@0
FDT: fdt@luton_pcb091
## Checking hash(es) for FIT Image at 80100000 ...
Hash(es) for Image 0 (kernel@0): sha1+
Hash(es) for Image 1 (fdt@luton_pcb091): sha1+
但是，当我尝试引导内核时，u-boot出现以下错误:
However, when I attempt to boot the kernel, u-boot gives the following error:
luton # bootm 0x80100000
## Loading kernel from FIT Image at 80100000 ...
Using 'conf@default' configuration
Trying 'kernel@0' kernel subimage
Description: Linux 5.11.11
Type: Kernel Image
Compression: gzip compressed
Data Start: 0x801000c0
Data Size: 5167511 Bytes = 4.9 MiB
Architecture: MIPS
OS: Linux
Load Address: 0x80100000
Entry Point: 0x809898f4
Hash algo: sha1
Hash value: b963ed48f45e332bd5df263dd69d69c3818e6586
Verifying Hash Integrity ... sha1+ OK
Uncompressing Kernel Image
Error: inflate() returned -3
gzip compressed: uncompress error -1
Must RESET board to recover
内核大小远低于 CONFIG_SYS_BOOTM_LEN (16MB)，所以我不认为这是此错误的根本原因.
The size of the kernel is well below the limit defined by CONFIG_SYS_BOOTM_LEN (16MB) so I don't believe that is the root cause of this error.
用于生成 itb 的 vmlinux.bin.gz 是有效的gzip存档，并且解压缩后的大小也小于 CONFIG_SYS_BOOTM_LEN 限制:
The vmlinux.bin.gz used to generate the itb is a valid gzip archive and the decompressed size is also less than the CONFIG_SYS_BOOTM_LEN limit:
$ file vmlinux.bin.gz
vmlinux.bin.gz: gzip compressed data, max compression, from Unix, original size modulo 2^32 11494800
我尝试使用未压缩的 vmlinux.bin 创建 itb 文件(我只是编辑了 vmlinux.its 以包含 data=/incbin/("vmlinux.bin"); 和 compression ="none"; 以及 readelf -h vmlinux 指示的入口地址)但是尝试启动时收到以下错误:
I have tried creating the itb file using the uncompressed vmlinux.bin (I simply edited vmlinux.its to have data = /incbin/("vmlinux.bin"); and compression = "none"; and the entry address indicated by readelf -h vmlinux) but I receive the following error when trying to boot:
luton # bootm ${loadaddr}
## Loading kernel from FIT Image at 80100000 ...
Using 'conf@luton_pcb091' configuration
Trying 'kernel@0' kernel subimage
Description: Linux 5.11.0
Type: Kernel Image
Compression: uncompressed
Data Start: 0x801000c0
Data Size: 11584912 Bytes = 11 MiB
Architecture: MIPS
OS: Linux
Load Address: 0x80100000
Entry Point: 0x809898f4
Hash algo: sha1
Hash value: d13175476fd38269a02a3e85bef53419092c01e1
Verifying Hash Integrity ... sha1+ OK
## Loading fdt from FIT Image at 80100000 ...
Using 'conf@luton_pcb091' configuration
Trying 'fdt@luton_pcb091' fdt subimage
Description: img,luton_pcb091 Device Tree
Type: Flat Device Tree
Compression: uncompressed
Data Start: 0x80c0c758
Data Size: 2303 Bytes = 2.2 KiB
Architecture: MIPS
Hash algo: sha1
Hash value: daa8a8147bbce692d81383af7b748a763212bb24
Verifying Hash Integrity ... sha1+ OK
Booting using the fdt blob at 0x80c0c758
Loading Kernel Image
ERROR: new format image overwritten - must RESET the board to recover
查看 common/bootm.c 中的 bootm_load_os ，看来这个错误告诉我我要引导的内核之间有一些重叠...某事，我不确定是什么.
Looking at bootm_load_os in common/bootm.c it appears that this error is telling me that there is some overlap between the kernel I'm trying to boot and... something, I'm not sure of what.
这是内核5.11生成的 vmlinux.its :
Here is vmlinux.its generated by kernel 5.11:
/* SPDX-License-Identifier: GPL-2.0 */
/dts-v1/;
/ {
description = "Linux 5.11.11";
#address-cells = <1>;
images {
kernel@0 {
description = "Linux 5.11.11";
data = /incbin/("vmlinux.bin.gz");
type = "kernel";
arch = "mips";
os = "linux";
compression = "gzip";
load = /bits/ 32 <0xffffffff80100000>;
entry = /bits/ 32 <0xffffffff809898f4>;
hash@0 {
algo = "sha1";
};
};
};
configurations {
default = "conf@default";
conf@default {
description = "Generic Linux kernel";
kernel = "kernel@0";
};
};
};
/* SPDX-License-Identifier: (GPL-2.0 OR MIT) */
/ {
images {
fdt@luton_pcb091 {
description = "MSCC Luton PCB091 Device Tree";
data = /incbin/("boot/dts/mscc/luton_pcb091.dtb");
type = "flat_dt";
arch = "mips";
compression = "none";
hash@0 {
algo = "sha1";
};
};
};
configurations {
pcb091 {
description = "Luton Linux kernel";
kernel = "kernel@0";
fdt = "fdt@luton_pcb091";
};
};
};
binwalk 并不表示ITB中的 gzip 数据无效:
binwalk doesn't indicate that the gzip data in the ITB is invalid:
$ binwalk vmlinux.gz.itb
DECIMAL HEXADECIMAL DESCRIPTION
--------------------------------------------------------------------------------
0 0x0 device tree image (dtb)
192 0xC0 gzip compressed data, maximum compression, from Unix, last modified: 1970-01-01 00:00:00 (null date)
3960903 0x3C7047 MySQL ISAM compressed data file Version 10
5167968 0x4EDB60 device tree image (dtb)
mkimage版本2020.01 由buildroot作为 host-uboot-tools-2020.01
mkimage version 2020.01 is built by buildroot as part of host-uboot-tools-2020.01
根据Tom Rini的建议，我更改了FIT映像的loadaddr，并且不再收到 uncompress 错误，但是系统仍然没有启动.我已将其移至后续问题.
As per the suggestion from Tom Rini, I changed the loadaddr of the FIT image and no longer receive the uncompress error, however the system still does not appear to boot. I've moved this to a follow up question.
推荐答案
您遇到的最后一个问题:
The final problem you run in to:
错误:新格式的图片已被覆盖-必须重置板才能恢复
ERROR: new format image overwritten - must RESET the board to recover
是因为您已将映像加载到与入口点相同的位置的内存中，但需要将其加载到其他位置的内存中，以便U-Boot可以解压缩映像并将内容放置在其加载地址中设定为.由于您有128MB的内存，因此应该可以从一开始就将其设置为+32或+ 64MB，然后一切正常.
is because you've loaded the image in to memory in the same location as the entry point but you need to load it in to memory somewhere else so that U-Boot can unpack the image and put the contents where their load address is set to. Since you have 128MB of memory you should be able to put it at +32 or +64MB from start and then things should work.
这篇关于u-boot:即使内核小于最大BOOTM_LEN，也无法引导linux内核的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
