mirror of
https://github.com/winfsp/winfsp.git
synced 2025-04-22 08:23:05 -05:00
82 lines
4.2 KiB
Plaintext
82 lines
4.2 KiB
Plaintext
= WinFsp Debugging Setup
|
|
|
|
In this article I will describe the debugging setup used for WinFsp. Note that my debugging setup is somewhat peculiar, because all development and debugging is done on a Mac computer using two Windows virtual machines: one for development and one for debugging! However my description below should work for a one or two virtual machine setup.
|
|
|
|
WinFsp is being developed on Windows 10 and debugged and tested on Windows 8 (although it should run correctly on Windows Vista and higher). You will need some virtualization software (I use VirtualBox 5), you will also need a fresh installation of Windows and to configure it properly for kernel debugging and running test signed drivers:
|
|
|
|
* Create a Windows VM with a descriptive name (e.g. Win8DBG). Mine has a single CPU and just 2GB of memory.
|
|
* Configure your VM for Host Only Networking. This will be used for WinDbg debugging and for deploying WinFsp.
|
|
* Install Windows 8 on Win8DBG. Windows 8 is the minimum version of Windows that supports kernel network debugging.
|
|
* I would recommend not to install your virtualization software guest additions to minimize issues with your debugging VM.
|
|
* Configure Win8DBG for running test signed drivers:
|
|
+
|
|
----
|
|
bcdedit.exe -set testsigning on
|
|
----
|
|
* Configure Win8DBG for debugging over the network:
|
|
+
|
|
----
|
|
bcdedit /debug on
|
|
bcdedit /dbgsettings net hostip:W.X.Y.Z port:NNNN key:KKKK
|
|
----
|
|
** Note that if you configure your VM with multiple network adapters you must also specify the correct `busparams` argument. You can find the correct `busparams` from the Windows Device Manager. For example, here are the settings on one of my VM's:
|
|
+
|
|
----
|
|
>bcdedit /dbgsettings
|
|
busparams 0.8.0
|
|
key 1.1.1.1
|
|
debugtype NET
|
|
hostip 192.168.56.11
|
|
port 50000
|
|
dhcp Yes
|
|
The operation completed successfully.
|
|
----
|
|
* Enable DbgPrint on Win8DBG. Create the following key/value in the registry:
|
|
+
|
|
----
|
|
Windows Registry Editor Version 5.00
|
|
|
|
[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Debug Print Filter]
|
|
"DEFAULT"=dword:0000000f
|
|
----
|
|
* Create a directory on Win8DBG where you will be deploying WinFsp. I use a subdirectory of the Downloads directory:
|
|
+
|
|
----
|
|
C:\Users\USERNAME\Downloads\winfsp
|
|
----
|
|
* Make the directory available outside the VM using Windows networking. You can use this new Windows share as an easy means to deploy WinFsp.
|
|
+
|
|
----
|
|
copy build\VStudio\build\Debug\winfsp-x64.sys \\Win8DBG\Users\USERNAME\Downloads\winfsp
|
|
----
|
|
* Enable Driver Verifier for WinFsp on Win8DBG. The easiest way to do so is to run `verifier` from the command line.
|
|
* For faster edit-compile-test cycles I strongly recommend to use your virtualization software snapshot feature. For example, in my Win8DBG VM after I set it up exactly how I wanted it, I took a snapshot while the VM was running. Now whenever I want to test WinFsp, I restart that same snapshot and within 3-4 seconds I have a new VM ready for use. Even more importantly whenever there is a hard crash on the VM (happens a lot when developing Windows drivers) I can simply close the crashed VM and restart a new one.
|
|
* On your development machine configure WinDbg to use the Microsoft public symbol servers. From the main menu select File > Symbol File Path and enter:
|
|
+
|
|
----
|
|
SRV*C:\Users\USERNAME\AppData\Local\Temp\SymbolCache*http://msdl.microsoft.com/download/symbols
|
|
----
|
|
* You can now run WinDbg and from the main menu select File > Kernel Debug, then enter the appropriate port number and key. Alternatively you can use the following windbg command line:
|
|
+
|
|
----
|
|
windbg -k net:port=NNNN,key=KKKK
|
|
----
|
|
* Checkout the `tools/deploy.bat` and `tools/debug.bat` batch files in the source distribution to see how I deploy and debug WinFsp.
|
|
|
|
== Debugging a user mode process from kernel mode WinDbg
|
|
|
|
In order to debug a user mode process from a kernel mode WinDbg session, break into the debugger and issue the following commands:
|
|
|
|
----
|
|
kd> !gflag +ksl
|
|
kd> sxe ld MODULE-NAME.exe
|
|
----
|
|
|
|
Restart the debugger and it will break within process creation. You can now set a breakpoint at your process wmain (or main, etc.):
|
|
|
|
----
|
|
kd> bp MODULE_NAME!wmain
|
|
----
|
|
|
|
Restart the debugger and it will stop at your program's entry point.
|