Source: initramfs-tools Version: 0.130 Severity: wishlist The line 56-59 of unmkinitramfs goes:
# There may be a prepended uncompressed archive. cpio # won't tell us the true size of this so we have to # parse the headers and padding ourselves. This is # very roughly based on linux/lib/earlycpio.c The claim "cpio won't tell us the true size of this ..." doesn't have any explicit reference to substantiate its claim while my uneducated simple use of cpio telling me the true file size without the tailing garbage ;-) For example: $ cpio -i -t </initrd.img >/dev/null 48 blocks So the uncompressed cpio file size is 512*48 BYTES. With some simple experimentation with cpio, I realize cpio always create file size in multiple of 512 bytes and it treat 512 bytes as a block. I can extract tailing basic initrd image file as subinitrd.img with: $ dd if=/initrd.img of=subinitrd.img bs=512 skip=48 At least on my recent Debian system, this subinitrd.img is a nicely extracted gzipped cpio archive. I am sure you had a reason why you made extensive binary file tracing code. If it was previous bug in cpio, it's nice to reference it. If there are some non-GNU/Linux cpio implementations having such problems, it's nice to be specific. It seems GNU version of cpio reports its true file size in blocks whenever with -i option. If this block based file size identification is OK, please consider using it to simplify the code. == Background == I was thinking to update initramfs related Debian wiki pages and realized simple method I was using seems to be problematic if your comment has some history behind. https://wiki.debian.org/initramfs Osamu -- Package-specific info: -- initramfs sizes -rw-r--r-- 1 root root 27M Mar 28 01:22 /boot/initrd.img-4.14.0-3-amd64 -- /proc/cmdline BOOT_IMAGE=/boot/vmlinuz-4.14.0-3-amd64 root=UUID=fde2800b-8afc-42e0-87b2-d7c8909dcea0 ro -- resume RESUME=UUID=4e3bd2a9-a62f-4d3f-9945-0719726af7c5 -- /proc/filesystems btrfs ext3 ext2 ext4 fuseblk -- lsmod Module Size Used by fuse 118784 3 snd_hda_codec_hdmi 57344 1 intel_rapl 24576 0 x86_pkg_temp_thermal 16384 0 intel_powerclamp 16384 0 coretemp 16384 0 kvm_intel 225280 0 kvm 700416 1 kvm_intel irqbypass 16384 1 kvm crct10dif_pclmul 16384 0 crc32_pclmul 16384 0 iTCO_wdt 16384 0 iTCO_vendor_support 16384 1 iTCO_wdt snd_hda_codec_realtek 106496 1 i915 1613824 25 snd_hda_codec_generic 86016 1 snd_hda_codec_realtek ghash_clmulni_intel 16384 0 intel_cstate 16384 0 intel_uncore 131072 0 snd_soc_rt5640 118784 0 intel_rapl_perf 16384 0 drm_kms_helper 192512 1 i915 snd_hda_intel 45056 10 joydev 24576 0 snd_soc_rl6231 16384 1 snd_soc_rt5640 pcspkr 16384 0 serio_raw 16384 0 evdev 28672 12 mei_me 45056 0 snd_hda_codec 151552 4 snd_hda_intel,snd_hda_codec_hdmi,snd_hda_codec_generic,snd_hda_codec_realtek drm 438272 16 i915,drm_kms_helper snd_hda_core 90112 5 snd_hda_intel,snd_hda_codec,snd_hda_codec_hdmi,snd_hda_codec_generic,snd_hda_codec_realtek lpc_ich 28672 0 i2c_algo_bit 16384 1 i915 mei 114688 1 mei_me sg 36864 0 mfd_core 16384 1 lpc_ich snd_hwdep 16384 1 snd_hda_codec shpchp 40960 0 snd_soc_core 258048 1 snd_soc_rt5640 snd_compress 24576 1 snd_soc_core snd_pcm 118784 6 snd_hda_intel,snd_hda_codec,snd_hda_core,snd_soc_rt5640,snd_hda_codec_hdmi,snd_soc_core video 45056 1 i915 snd_timer 36864 1 snd_pcm snd 94208 30 snd_compress,snd_hda_intel,snd_hwdep,snd_hda_codec,snd_timer,snd_hda_codec_hdmi,snd_hda_codec_generic,snd_hda_codec_realtek,snd_soc_core,snd_pcm soundcore 16384 1 snd intel_smartconnect 16384 0 acpi_pad 24576 0 button 16384 1 i915 parport_pc 32768 0 ppdev 20480 0 lp 20480 0 parport 57344 3 lp,parport_pc,ppdev loop 32768 0 dm_crypt 40960 0 ip_tables 28672 0 x_tables 40960 1 ip_tables autofs4 49152 3 ext4 720896 1 crc16 16384 1 ext4 mbcache 16384 1 ext4 jbd2 118784 1 ext4 fscrypto 32768 1 ext4 ecb 16384 0 btrfs 1339392 0 zstd_decompress 94208 1 btrfs zstd_compress 188416 1 btrfs xxhash 16384 2 zstd_compress,zstd_decompress raid10 57344 0 raid456 163840 0 async_raid6_recov 20480 1 raid456 async_memcpy 16384 2 raid456,async_raid6_recov async_pq 16384 2 raid456,async_raid6_recov async_xor 16384 3 async_pq,raid456,async_raid6_recov async_tx 16384 5 async_xor,async_pq,raid456,async_memcpy,async_raid6_recov xor 24576 2 async_xor,btrfs raid6_pq 122880 4 async_pq,btrfs,raid456,async_raid6_recov libcrc32c 16384 1 raid456 crc32c_generic 16384 0 raid1 45056 0 raid0 20480 0 multipath 16384 0 linear 16384 0 md_mod 159744 6 raid1,raid10,multipath,linear,raid0,raid456 dm_mirror 28672 0 dm_region_hash 20480 1 dm_mirror dm_log 20480 2 dm_mirror,dm_region_hash dm_mod 143360 3 dm_mirror,dm_log,dm_crypt hid_generic 16384 0 usbhid 57344 0 hid 131072 2 hid_generic,usbhid sr_mod 28672 0 sd_mod 53248 3 cdrom 69632 1 sr_mod crc32c_intel 24576 4 e1000e 282624 0 ahci 40960 2 ptp 20480 1 e1000e libahci 40960 1 ahci aesni_intel 188416 0 psmouse 167936 0 xhci_pci 16384 0 ehci_pci 16384 0 libata 274432 2 ahci,libahci xhci_hcd 241664 1 xhci_pci ehci_hcd 94208 1 ehci_pci aes_x86_64 20480 1 aesni_intel crypto_simd 16384 1 aesni_intel pps_core 20480 1 ptp cryptd 28672 3 crypto_simd,ghash_clmulni_intel,aesni_intel glue_helper 16384 1 aesni_intel scsi_mod 253952 4 sd_mod,libata,sr_mod,sg i2c_i801 28672 0 usbcore 286720 5 usbhid,ehci_hcd,xhci_pci,xhci_hcd,ehci_pci usb_common 16384 1 usbcore -- /etc/initramfs-tools/modules -- /etc/kernel-img.conf # Kernel image management overrides # See kernel-img.conf(5) for details do_symlinks = yes do_bootloader = no do_initrd = yes link_in_boot = no -- /etc/initramfs-tools/initramfs.conf MODULES=most BUSYBOX=auto KEYMAP=n COMPRESS=gzip DEVICE= NFSROOT=auto -- /etc/initramfs-tools/update-initramfs.conf update_initramfs=yes backup_initramfs=no -- /etc/crypttab # <target name> <source device> <key file> <options> -- /proc/mdstat Personalities : [linear] [multipath] [raid0] [raid1] [raid6] [raid5] [raid4] [raid10] unused devices: <none> -- mkinitramfs hooks /etc/initramfs-tools/hooks/: /usr/share/initramfs-tools/hooks: amd64_microcode bcache btrfs cryptgnupg cryptkeyctl cryptopenct cryptopensc cryptpassdev cryptroot cryptroot-unlock dmraid dmsetup fsck fuse intel_microcode keymap klibc-utils kmod lvm2 mdadm ntfs_3g resume sg3-utils thermal udev zz-busybox -- System Information: Debian Release: buster/sid APT prefers testing APT policy: (500, 'testing'), (500, 'stable') Architecture: amd64 (x86_64) Kernel: Linux 4.14.0-3-amd64 (SMP w/4 CPU cores) Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8), LANGUAGE=en_US.UTF-8 (charmap=UTF-8) Shell: /bin/sh linked to /bin/dash Init: systemd (via /run/systemd/system) LSM: AppArmor: enabled -- no debconf information
