Inital commit

.vuepress/config.js

@@ -239,6 +239,7 @@ module.exports = {
 		        },
                 ['/Universal/irq', 'IRQ Fix'],
 				['/Universal/spoof', 'GPU Spoof'],
+				['/Universal/apic', 'APIC Patching'],
             ]
         },
         {

Universal/apic.md

@@ -0,0 +1,71 @@
+# Patching the APIC table
+
+An odd issue some HEDT users may experience is a kernel panic relating to more cores defined in APIC than actually present:
+
+```
+panic(cpu 0 caller 0x......): "x86_validate topology() 32 threads but 33 registered from MADT~0/...
+```
+
+The reason for this kernel panic is due to macOS's assumption that the first CPU in ACPI is always enabled, which on servers and HEDT systems may not always true.
+
+To get around this, we want to patch our APIC table to point the first CPU entry to an active CPU.
+
+
+## Dumping your DSDT and APIC tables
+
+Dumping your DSDT and APIC table is quite easy, however some of the methods mentioned in [Getting a copy of our DSDT](../Manual/dumpmd) may not provide you will all the needed files. Methods that will provide a full dump:
+
+* acpidump.exe
+  * Just run the program, don't give any specific arguments
+* Clover's F4
+* UEFI Shell using acpidump.efi
+* OpenCore's SysReport quirk
+
+And don't forget to follow the decompile guide as well: [Compiling and decompiling ACPI Tables](../Manual/compile.md)
+
+
+## Examining our ACPI table
+
+So lets take a look at our APIC table first:
+
+![](../images/Universal/apic-md/apic-table.png)
+
+Here we can see a list of all the CPU threads, and info about each one. Lets look at the first `[Processor Local APIC]` entry:
+
+```
+[02Ch 0044   1]                Subtable Type : 00 [Processor Local APIC]
+[02Dh 0045   1]                       Length : 08
+[02Eh 0046   1]                 Processor ID : 00
+[02Fh 0047   1]                Local Apic ID : 02
+[030h 0048   4]        Flags (decoded below) : 00000001
+                           Processor Enabled : 1
+                      Runtime Online Capable : 0
+```
+
+Here we're given some important info, but the most important part:
+```
+Processor ID : 00
+```
+
+This value is what matches up the APIC's table entry to your DSDT, and is passed to macOS to determine the first CPU entry. And here we get a glimpse into what might be causing our kernel panic.
+
+Next open your DSDT and search for `Processor`:
+
+![](../images/Universal/apic-md/dsdt-processor-entry.png)
+
+Here we're given some important info regarding the first CPU:
+
+```
+Processor (C000, 0x80, 0x00000410, 0x06)
+```
+
+If we check the [ACPI Spec](https://uefi.org/sites/default/files/resources/ACPI_6_3_final_Jan30.pdf), section 19.6.108, we see the info is parsed as follows:
+
+```
+Processor (ProcessorName, ProcessorID, PBlockAddress, PblockLength)
+```
+
+
+Now if we look at the `ProcessorID` section, we notice it's `0x80`, but this doesn't match up with the first entry in our APIC table(`00`). Now we can get a clearer idea of what's wrong with out APIC table and why it kernel panics.
+
+## Patching the APIC table