plano

   1 intro
   2         linux
   3                 version history/evolution/compatibility DO A LITTLE
   4                 constant change, book is already outdated
   5                 current versioning/development model
   6                 modules
   7                 build dependencies
   8                 running new/bleeding-edge kernels
   9
  10 concepts
  11         kernel/user space
  12                 rings/levels/modes
  13                 memory protection/segmentation/pagination
  14                 library calls
  15                 allowed uses (floating point forbidden)
  16                 concurrency
  17                 small stack
  18         libc/system calls
  19         operating system functions
  20                 process management
  21                         concurrency
  22                         communication/IPC, scheduling
  23                 memory management
  24                         address space
  25                         virtual memory
  26                 filesystems
  27                 networking
  28                 device, I/O
  29         robustness/security
  30                 error checking
  31                 kernel space code
  32                 programming errors and bugs
  33                 restrict some operations to privileged users
  34                 do not send unzeored data (information leak)
  35                 do not trust received data (malformed data) (exploit)
  36                 risks for the machine/system/data
  37
  38 basics
  39         Makefile
  40         Kconfig DO?
  41         building linux DO?
  42         build
  43         init/exit
  44         module macros
  45         module parameters
  46         config/build time options/parameters
  47         sysfs interface for modules DO?
  48         printk
  49         module loading/unloading/handling
  50
  51 VFS
  52         center/hub/interface
  53         char/block/procfs/sysfs: all go through VFS to device
  54         fops is the main structure in linux
  55         FS on top of block devices
  56                 block layer
  57                 exception: some on top of MTD devices
  58
  59 device driver subsystem
  60         buses
  61         device classes
  62         interfaces
  63                 dev file
  64                 sysfs
  65                 procfs
  66                 sysctl DO?
  67                 netlink DO?
  68
  69 char device
  70 procfs
  71 sysfs
  72 block device DO? STUDY
  73 network device DO? STUDY
  74 terminal/serial device DO? STUDY
  75
  76 debugging techniques
  77         printk/procfs
  78         debugfs DO? STUDY
  79         kgdb DO?
  80         trace DO?
  81         kprobe DO?
  82
  83 C basics
  84         container_of (struct embedding)
  85         fops/*ops (function pointers)
  86         IS_ERR (pointers and error values)
  87
  88 data structures
  89         list_head
  90         bitmap
  91         trees DO? STUDY rbtree
  92         idr DO?
  93         any hash implementation DO? STUDY
  94
  95 contexts
  96         user context (current, copy_from_user, schedule) STUDY schedule
  97         interrupt context
  98         workqueue is user context
  99         sleep == schedule
 100
 101 concurrency
 102         SMP systems
 103         locking
 104         spinlock: disable scheduler
 105         semaphore/mutex sleeps
 106         per-cpu variables STUDY
 107         atomic
 108         RCU DO?
 109
 110 memory allocation
 111         kobject refcount MENTION
 112         slab STUDY
 113                 multiple implementations
 114                 space efficient (tables for different object sizes)
 115                 concurrency efficient (per-cpu tables)
 116         kmalloc
 117                 uses slab STUDY
 118         vmalloc
 119                 linux memory layout
 120
 121 scheduling/timing
 122         schedule{,_timeout}
 123         timer
 124         workqueue
 125         completion/wait_head
 126         tasklets DO? STUDY
 127
 128 portability
 129         readl/writel/etc
 130         be16_to_cpu/etc
 131
 132 interrupt
 133         {request,free}_irq
 134         interrupt context
 135         tasklet/workqueue/postpone
 136
 137 buses
 138         PCI bus DO?
 139         USB bus DO?
 140         some bus: SPI, I2C, parport DO?
 141
 142 device classes
 143         some class: cdrom, backlight, input, misc DO?
 144
 145 kobject DO? advanced
 146         refcounting
 147
 148 STUDY:
 149         module owner, concurrency, reference counting