x86/dumpstack: Explain the reasoning for the prologue and buffer size

	printk("%s %s%pB\n", log_lvl, reliable ? "" : "? ", (void *)address);

}

/*

 * There are a couple of reasons for the 2/3rd prologue, courtesy of Linus:

 *

 * In case where we don't have the exact kernel image (which, if we did, we can

 * simply disassemble and navigate to the RIP), the purpose of the bigger

 * prologue is to have more context and to be able to correlate the code from

 * the different toolchains better.

 *

 * In addition, it helps in recreating the register allocation of the failing

 * kernel and thus make sense of the register dump.

 *

 * What is more, the additional complication of a variable length insn arch like

 * x86 warrants having longer byte sequence before rIP so that the disassembler

 * can "sync" up properly and find instruction boundaries when decoding the

 * opcode bytes.

 *

 * Thus, the 2/3rds prologue and 64 byte OPCODE_BUFSIZE is just a random

 * guesstimate in attempt to achieve all of the above.

 */

void show_opcodes(u8 *rip, const char *loglvl)

{

	unsigned int code_prologue = OPCODE_BUFSIZE * 2 / 3;