Windows BSOD

2023-10-13T12:30:11Z

Ichundes: Set symbol path using symfix/sympath

== Windows Crash Dumps ==

If you do managed to get a Blue Screen Of Death (BSOD), Windows should in theory write a crash dump file to:

C:\Windows\MEMORY.DMP

The dump file can be analyzed with [http://windbg.org WinDbg.exe]

Debug builds of ZFSin include debugging symbols to assist in dump analysis which are located at:

C:\Program Files\OpenZFS On Windows\symbols\

=== WinDbg.exe at the Command Line ===

Once installed, WinDbg.exe can be run from a CMD.com or PowerShell terminal with Administrative privileges:

WinDbgX.exe -y ‘C:\Program Files\OpenZFS On Windows\symbols\’ -z C:\Windows\MEMORY.DMP

This will launch the application and you can perform dump analysis with:

kd> !analyze -v

To run the analysis in a single command:

WinDbgX.exe -y ‘C:\Program Files\OpenZFS On Windows\symbols\’ -z C:\Windows\MEMORY.DMP -c !analyze -v

=== WinDbg.exe in the GUI ===

Launch WinDbg.exe and set the symbol path:

kd> .symfix c:\cache
kd> .sympath+ C:\Program Files\OpenZFS On Windows\symbols
kd> .reload

So that it can load both the symbols from Microsoft, and from the installed Open ZFS directory.

Open the crash dump file with:

File: Open crash dump
C:\Windows\MEMORY.DMP

Perform the analysis:

kd> !analyze -v

Should at least show the stack.

<gallery mode="packed-hover">
Image:minidump1.png|''Set symbol path''
Image:minidump2.png|''Add path''
Image:minidump3.png|''Load crash dump''
Image:minidump4.png|''Locate minidump''
Image:minidump5.png|''minidump loading''
Image:minidump6.png|''analyze with stack''
</gallery>

=== Example Crash report ===

A successful crash dump would look something like:

ZFSin!zfs_range_lock_reader+0x290 [c:\src\zfsin\zfsin\zfs\module\zfs\zfs_rlock.c @ 417] C/C++/ASM
ZFSin!zfs_range_lock+0x16d [c:\src\zfsin\zfsin\zfs\module\zfs\zfs_rlock.c @ 453] C/C++/ASM
ZFSin!zil_lwb_commit+0x99f [c:\src\zfsin\zfsin\zfs\module\zfs\zil.c @ 1570] C/C++/ASM
ZFSin!zil_process_commit_list+0x30e [c:\src\zfsin\zfsin\zfs\module\zfs\zil.c @ 2182] C/C++/ASM
ZFSin!zil_commit_writer+0x111 [c:\src\zfsin\zfsin\zfs\module\zfs\zil.c @ 2318] C/C++/ASM

If you get only ZFSin+0x"hex-number" it means it is not reading the debug symbols correctly, to be able to convert the hex-number into a function name.

=== Debug Print Buffer ===

Windows features a circular debug print buffer which can also be written to disk:

Old

kd> r $t0 = poi(ZFSin!cbuf)
kd> .writemem C:\Users\<your Windows username>\Desktop\cbuf.txt $t0 L100000

New

kd> r $t0 = poi(OpenZFS!cbuf)
kd> .writemem C:\Users\<your Windows username>\Desktop\cbuf.txt $t0 L100000

Do not worry if you get a message about short write, it just means you have not yet filled the buffer.

This will include -EB- at the end of the buffer.
Do not worry if the rest of the buffer has "@" (nul) symbols, it just means the buffer was not yet full.

Please provide the contents of the dump analysis and cbuf.txt in you ZFSin in your crash-related tickets.

Windows BSOD

2023-10-13T12:26:54Z

Ichundes: easier way to write cbuf without having to copy and paste the address

== Windows Crash Dumps ==

If you do managed to get a Blue Screen Of Death (BSOD), Windows should in theory write a crash dump file to:

C:\Windows\MEMORY.DMP

The dump file can be analyzed with [http://windbg.org WinDbg.exe]

Debug builds of ZFSin include debugging symbols to assist in dump analysis which are located at:

C:\Program Files\OpenZFS On Windows\symbols\

=== WinDbg.exe at the Command Line ===

Once installed, WinDbg.exe can be run from a CMD.com or PowerShell terminal with Administrative privileges:

WinDbgX.exe -y ‘C:\Program Files\OpenZFS On Windows\symbols\’ -z C:\Windows\MEMORY.DMP

This will launch the application and you can perform dump analysis with:

kd> !analyze -v

To run the analysis in a single command:

WinDbgX.exe -y ‘C:\Program Files\OpenZFS On Windows\symbols\’ -z C:\Windows\MEMORY.DMP -c !analyze -v

=== WinDbg.exe in the GUI ===

Launch WinDbg.exe and set the Symbol path in:
<nowiki>
File > Symbol File Path:
srv*c:\cache*https://msdl.microsoft.com/download/symbols;C:\Program Files\OpenZFS On Windows\symbols
</nowiki>

So that it can load both the symbols from Microsoft, and from the installed Open ZFS directory.

Open the crash dump file with:

File: Open crash dump
C:\Windows\MEMORY.DMP

Perform the analysis:

kd> !analyze -v

Should at least show the stack.

<gallery mode="packed-hover">
Image:minidump1.png|''Set symbol path''
Image:minidump2.png|''Add path''
Image:minidump3.png|''Load crash dump''
Image:minidump4.png|''Locate minidump''
Image:minidump5.png|''minidump loading''
Image:minidump6.png|''analyze with stack''
</gallery>

=== Example Crash report ===

A successful crash dump would look something like:

ZFSin!zfs_range_lock_reader+0x290 [c:\src\zfsin\zfsin\zfs\module\zfs\zfs_rlock.c @ 417] C/C++/ASM
ZFSin!zfs_range_lock+0x16d [c:\src\zfsin\zfsin\zfs\module\zfs\zfs_rlock.c @ 453] C/C++/ASM
ZFSin!zil_lwb_commit+0x99f [c:\src\zfsin\zfsin\zfs\module\zfs\zil.c @ 1570] C/C++/ASM
ZFSin!zil_process_commit_list+0x30e [c:\src\zfsin\zfsin\zfs\module\zfs\zil.c @ 2182] C/C++/ASM
ZFSin!zil_commit_writer+0x111 [c:\src\zfsin\zfsin\zfs\module\zfs\zil.c @ 2318] C/C++/ASM

If you get only ZFSin+0x"hex-number" it means it is not reading the debug symbols correctly, to be able to convert the hex-number into a function name.

=== Debug Print Buffer ===

Windows features a circular debug print buffer which can also be written to disk:

Old

kd> r $t0 = poi(ZFSin!cbuf)
kd> .writemem C:\Users\<your Windows username>\Desktop\cbuf.txt $t0 L100000

New

kd> r $t0 = poi(OpenZFS!cbuf)
kd> .writemem C:\Users\<your Windows username>\Desktop\cbuf.txt $t0 L100000

Do not worry if you get a message about short write, it just means you have not yet filled the buffer.

This will include -EB- at the end of the buffer.
Do not worry if the rest of the buffer has "@" (nul) symbols, it just means the buffer was not yet full.

Please provide the contents of the dump analysis and cbuf.txt in you ZFSin in your crash-related tickets.

OpenZFS on OS X - User contributions [en]

Windows BSOD

Windows BSOD