Operating System Startup Process-hardware self-check + system boot + system loading + system logon II-reprint

3. kernel loading phase
ntldr , the information is organized into an internal structure, start ntldr ntoskrnl.exe Program , and boot. INI information in the file and hardware and software information in the Registry are transmitted to ntoskrnl.exe program -- Windows XP kernel.

1(Ntoskrnl.exeAnd Hardware Abstraction Layer (Hal. dll) Load to memory

In the kernel loading stage,NtldrLoadNtokrnl.exeBut it is not initialized.NextNtldrLoad the hardware abstraction layer (Hal,Hal. dll). 2Load Control Set Information
In this process,NtldrFrom the RegistryHKEY_LOCAL_MACHINE \ SYSTEMLocation readingSelectTo determine which control set (Control Set) Information will be loaded and the device driver to be loaded during startup will be determined. The control set contains the driver of the device and the services to be loaded.
3Load device drivers and services

in this step, the system BIOS , start to load device drivers and services.

device drivers, ntldr loads HKEY_LOCAL_MACHINE \ SYSTEM \ service \... lower Start the key value is 0 is the underlying device driver.

when used as control set current control set , ntldr control is passed to Windows XP kernel ntoskrnl. EXE .

The kernel loading stage ends, followed by the kernel initialization stage.

IV,Initialize the kernel

Color Windows XPOfLogoThe progress bar is displayed in the center of the screen.4Task:
1The kernel uses the data collected during hardware detection to createHKEY_LOCAL_MACHINE \ hardwareKey.
2, The kernel by referencingHKEY_LOCAL_MACHINE \ SYSTEM \ currentCopy the default valueControl SetTo createClone control set.Clone control setThe configuration is a backup of computer data, and does not include changes during startup.
3System initialization and Device Driver Loading
The kernel initializes the underlying drivers that are loaded during kernel loading, and then the kernel scansHKEY_LOCAL_MACHINE \ SYSTEM \ CurrentControlSet \ service \...LowerStartThe key value is1.These device drivers are initialized when they are loaded. If an error occurs, the kernel usesErrorcontrolKey value to determine how to handle.
StartKey ValueIs3Error marks as crisis/Key: when the system encounters an error for the first timeLastknowngood control setRestart, if you useLastknowngood control setAn error still occurs during startup. The system reports that the startup failed, the error message is displayed, and the system stops the startup;
The value is2The error is serious, the system fails to start andLastknowngood control setRestart, if the system is already in useLastknowngoodValue, which ignores the error and continues to start;
The value is1When the error is normal, the system will generate an error message, but it will still ignore this error and continue to start; the value is0The system does not display any error information and continues running..
4Start Session ManagerSession Manager

The kernel starts the Session Manager (Session Manager),This isSmss.exeProgram, its function is as follows:

( 1 ) create system environment variables
( 2 ) create a virtual memory page file
( 3 ) started Windows XP advanced subsystems and services
( 4 ) the Win32 subsystem

Kernel Initialization is complete.

 

5. User Logon phase
A in this process, Windows the subsystem starts winlogon.exe , which is a system service, it is used to support logon and logout of Windows users. winlogon.exe you can do the following:

1 . Start the service subsystem ( services.exe ).

2 . Enable local security authorization ( Local Security Authority, lsa ) process ( lsass.exe ), Windows XP Professional the welcome screen or Login Dialog Box is displayed, the system may still initialize the driver that has not been completed in the background.

3 . When the logon start prompt is displayed, analyze crtl + ALT + DEL keys.

4,Call a graphical identification and authentication component to prompt you to enter a valid user name or password, collect the user's account and password, and then securely transmit the informationLSAFor authentication. If the information provided by the user is correct and passes authentication, the user is allowed to access the system.Then, the user successfully logs on to the operating system.

Note that if your computer only has AdministratorThis user will be displayed on the welcome screen Administrator User item. If not only Administrator Users and other users that can log on interactively. The welcome screen only displays Administrator Other users without displaying Administrator User.
If you want Administrator What should I do when a user logs on? It's actually quite simple. Press it twice on the welcome screen. Crtl + ALT + DEL Key combination to open the standard Logon window. You can enter Administrator To log on as the highest administrator.
B service controller performs and scans HKEY_LOCAL_MACHINE \ SYSTEM \ CurrentControlSet \ servives to check whether services need to be loaded, service controller Search Start the key value is 2 or higher, the Service follows the Start value and dependongroup and depandonservice .

plug-and-play device detection process

detects plug-and-play devices, It is actually asynchronous with the login process. The system firmware, hardware, device driver, and system features determine how to detect and enumerate new devices in Windows XP . When the plug-and-play component works properly, Windows XP detects new devices and assigns them system resources, if possible, install a proper driver for the new device.

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Only after the user successfully logs on to the computer,Windows XPIs considered to have been completed. After successful login, the system copiesClone control setToLastknowngood control setAfter this step is completed, the system has successfully guided.

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