vermagic

vermagic.md

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+# vermagic
+
+If the module does not match that of the kernel, `insmod` is unhappy and fails.
+
+Get it from kernel module:
+
+    modinfo mymod.ko
+
+Override it on module source:
+
+    MODULE_INFO(vermagic, "newver");
+
+On the Linux kernel 4.9.6, it is defined under `include/linux/vermagic.h`:
+
+    #define VERMAGIC_STRING                                                 \
+            UTS_RELEASE " "                                                 \
+            MODULE_VERMAGIC_SMP MODULE_VERMAGIC_PREEMPT                     \
+            MODULE_VERMAGIC_MODULE_UNLOAD MODULE_VERMAGIC_MODVERSIONS       \
+            MODULE_ARCH_VERMAGIC
+
+TODO can you get it from running kernel from userland? <https://lists.kernelnewbies.org/pipermail/kernelnewbies/2012-October/006306.html>
+
+Desktop `modprobe` has a flag to skip the check:
+
+	`--force-modversion`
+
+Looks like it just strips `modversion` information from the module, and then the kernel skips the check.