{"id":337,"date":"2012-08-13T21:29:11","date_gmt":"2012-08-13T21:29:11","guid":{"rendered":"http:\/\/rglinuxtech.com\/?p=337"},"modified":"2012-08-13T21:29:11","modified_gmt":"2012-08-13T21:29:11","slug":"apc-more-forensics","status":"publish","type":"post","link":"https:\/\/rglinuxtech.com\/?p=337","title":{"rendered":"APC – More Forensics.."},"content":{"rendered":"

Still trying to find a way round the ‘always boot to rom’ conundrum, and the results of my latest test are not looking too positive..
\nInstead of running the various parameters in the U-Boot environment, I entered the basic commands by hand:<\/p>\n

WMT # usb reset\n(Re)start USB...\nwmt.usb.param: 11:3\nusb select port D\nscanning bus for devices...\n\u00a01 USB Device(s) found\nscanning bus for storage devices...\n usb_request_sense\n\u00a0usb_request_sense\n\u00a0usb_request_sense\n\u00a0..... <repeated> .......\n\u00a0usb_request_sense\n\u00a0usb_request_sense\n\u00a0Device NOT ready\n\u00a0\u00a0 Request Sense returned 02 3A 00\n usb_request_sense\n\u00a0usb_request_sense\n... <repeated>......\n\u00a0usb_request_sense\n\u00a0usb_request_sense\n\u00a0Device NOT ready\n\u00a0\u00a0 Request Sense returned 02 3A 00\n4 Storage Device(s) found\nWMT # root=\/dev\/sdb2\nWMT # rootfstype=ext2\nWMT # fatload usb 1:1 0x1000000 uzImage.bin 400000\npart_offset : 800, cur_part : 1\nreading uzImage.bin\n.......................................................................................\n.........................................................\n\n2969256 bytes read\nWMT # fatload usb 1:1 1400000 initrd.gz 400000\npart_offset : 800, cur_part : 1\nreading initrd.gz\n.......................................................................................\n......................................................................\n\n3231913 bytes read\nWMT # bootm 0x1000000\n## Booting image at 01000000 ...\n\u00a0\u00a0 Image Name:\u00a0\u00a0 Linux-2.6.32.9-default\n\u00a0\u00a0 Image Type:\u00a0\u00a0 ARM Linux Kernel Image (uncompressed)\n\u00a0\u00a0 Data Size:\u00a0\u00a0\u00a0 2969192 Bytes =\u00a0 2.8 MB\n\u00a0\u00a0 Load Address: 00008000\n\u00a0\u00a0 Entry Point:\u00a0 00008000\n\u00a0\u00a0 Verifying Checksum ... OK\nOK\n\nStarting kernel ...\n\nUncompressing Linux....................................................................\n.......................................................................................\n....................... done, booting the kernel.<\/pre>\n
Then the main console on the monitor displayed a Kernel panic:<\/p>\n
.............\nVFS: Cannot open root device \"<NULL>\" or unknown-block(0,0)\nPlease append a correct \"root=\" boot option; here are the available partitions:\n1f00\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a013312 mtdblock0 (driver?)\n1f01\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0 2560 mtdblock1 (driver?)\n1f02\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0\u00a0 320 mtdblock2 (driver?)\n1f03\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0\u00a0\u00a0 64 mtdblock3 (driver?)\n1f04\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0\u00a0\u00a0 64 mtdblock4 (driver?)\n1f05\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0\u00a0\u00a0 64 mtdblock5 (driver?)\n1f06\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0 1024 mtdblock6 (driver?)\n1f07\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0 9216 mtdblock7 (driver?)\n1f08\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0 9216 mtdblock8 (driver?)\n1f09\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0 8192 mtdblock9 (driver?)\n1f0a\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0 6144 mtdblock10 (driver?)\n1f0b\u00a0\u00a0 \u00a0\u00a0\u00a0 262144 mtdblock11 (driver?)\n1f0c\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0 2048 mtdblock12 (driver?)\n1f0d\u00a0\u00a0 \u00a0\u00a0\u00a0 \u00a0 4096 mtdblock13 (driver?)\n1f0e\u00a0\u00a0 \u00a0\u00a0 1048576 mtdblock14 (driver?)\n1f0f\u00a0\u00a0 \u00a0\u00a0\u00a0 131072 mtdblock15 (driver?)\n1f10\u00a0\u00a0 \u00a0\u00a0\u00a0 615424 mtdblock16 (driver?)\nKernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,0)\nBacktrace:\n[<c00303a8>] (dump backtrace+0x0\/0x10c) from [<c0414ac8>] (dump_stcak+0x18\/0x1c)\n.......... etc .............<\/pre>\n
This would appear to confirm my previous theory, that the kernel code on the device is set to only<\/strong> boot to ram – in all<\/strong> cases.\u00a0\u00a0 If this is correct, then it makes the substitution of a ‘real’ Linux distro filesystem next to impossible.<\/p>\n
What is needed is a version of the APC kernel that allows the correct use of the root=\/dev\/sdb2 parameter to allow the root fs to be resident on the same disk that the system has booted from – as normal..<\/p>\n
Of course, the best scenario would be the availability of open-sourced drivers for all the APC components, including the WM8750 system-on-a-chip..\u00a0\u00a0 In reality, this process may well take some considerable time.<\/p>\n","protected":false},"excerpt":{"rendered":"
Still trying to find a way round the ‘always boot to rom’ conundrum, and the results of my latest test are not looking too positive.. Instead of running the various parameters in the U-Boot environment, I entered the basic commands by hand: WMT # usb reset (Re)start USB… wmt.usb.param: 11:3 usb select port D scanning bus for …<\/span> Continue reading →<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"footnotes":""},"categories":[2,3,5,6,16,19,20],"tags":[81,89,165,233,254,305,327],"class_list":["post-337","post","type-post","status-publish","format-standard","hentry","category-android","category-apc","category-compilation","category-crash-and-burn","category-linux-arm","category-opinion","category-performance-2","tag-always-boot-to-rom","tag-apc-2","tag-forensics","tag-kernel-panic","tag-manual-boot","tag-problem","tag-rootfs"],"_links":{"self":[{"href":"https:\/\/rglinuxtech.com\/index.php?rest_route=\/wp\/v2\/posts\/337","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/rglinuxtech.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/rglinuxtech.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/rglinuxtech.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/rglinuxtech.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=337"}],"version-history":[{"count":0,"href":"https:\/\/rglinuxtech.com\/index.php?rest_route=\/wp\/v2\/posts\/337\/revisions"}],"wp:attachment":[{"href":"https:\/\/rglinuxtech.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=337"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/rglinuxtech.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=337"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/rglinuxtech.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=337"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}