--- /dev/null
+#include <lwk/kernel.h>
+#include <lwk/task.h>
+#include <lwk/ptrace.h>
+#include <lwk/version.h>
+#include <lwk/kallsyms.h>
+#include <arch/msr.h>
+
+/**
+ * Prints a nicely formatted address to the console.
+ * This attempts to look up the symbolic name of the address.
+ */
+void
+printk_address(unsigned long address)
+{
+ unsigned long offset = 0, symsize;
+ const char *symname;
+ char namebuf[128];
+
+ symname = kallsyms_lookup(address, &symsize, &offset, namebuf);
+ if (!symname) {
+ printk(" [<%016lx>]\n", address);
+ return;
+ }
+ printk(" [<%016lx>] %s+0x%lx/0x%lx\n",
+ address, symname, offset, symsize);
+}
+
+
+/**
+ * Print a stack trace of the context.
+ */
+void
+kstack_trace(
+ void * rbp_v
+)
+{
+#ifndef CONFIG_FRAME_POINTER
+ printk( "Unable to generate stack trace "
+ "(recompile with CONFIG_FRAME_POINTER)\n" );
+ return;
+#endif
+
+ uint64_t * rbp = rbp_v;
+ if( rbp == 0 )
+ asm( "mov %%rbp, %0" : "=r"(rbp) );
+
+ int max_depth = 16;
+ printk( "Stack trace from RBP %p\n", rbp );
+
+ while( rbp && max_depth-- )
+ {
+ printk_address( rbp[1] );
+ rbp = (uint64_t*) *rbp;
+ }
+}
+
+
+/**
+ * Prints x86_64 general purpose registers and friends to the console.
+ * NOTE: This prints the CPU register values contained in the passed in
+ * 'struct pt_regs *'. It DOES NOT print the current values in
+ * the CPU's registers.
+ */
+void
+show_registers(struct pt_regs * regs)
+{
+ unsigned long cr0 = 0L, cr2 = 0L, cr3 = 0L, cr4 = 0L, fs, gs, shadowgs;
+ unsigned int fsindex, gsindex;
+ unsigned int ds, cs, es;
+ bool user_fault = (regs->rip < PAGE_OFFSET);
+ char namebuf[128];
+
+/*
+ printk("Task ID: %d Task Name: %s UTS_RELEASE: %s\n",
+ current ? current->id : -1,
+ current ? current->name : "BAD CURRENT",
+ UTS_RELEASE
+ );
+*/
+ printk("RIP: %04lx:%016lx (%s)\n", regs->cs & 0xffff, regs->rip,
+ (user_fault) ? "user-context"
+ : kallsyms_lookup(regs->rip, NULL, NULL, namebuf));
+ printk("RSP: %04lx:%016lx EFLAGS: %08lx ERR: %08lx\n",
+ regs->ss, regs->rsp, regs->eflags, regs->orig_rax);
+ printk("RAX: %016lx RBX: %016lx RCX: %016lx\n",
+ regs->rax, regs->rbx, regs->rcx);
+ printk("RDX: %016lx RSI: %016lx RDI: %016lx\n",
+ regs->rdx, regs->rsi, regs->rdi);
+ printk("RBP: %016lx R08: %016lx R09: %016lx\n",
+ regs->rbp, regs->r8, regs->r9);
+ printk("R10: %016lx R11: %016lx R12: %016lx\n",
+ regs->r10, regs->r11, regs->r12);
+ printk("R13: %016lx R14: %016lx R15: %016lx\n",
+ regs->r13, regs->r14, regs->r15);
+
+ asm("movl %%ds,%0" : "=r" (ds));
+ asm("movl %%cs,%0" : "=r" (cs));
+ asm("movl %%es,%0" : "=r" (es));
+ asm("movl %%fs,%0" : "=r" (fsindex));
+ asm("movl %%gs,%0" : "=r" (gsindex));
+
+ rdmsrl(MSR_FS_BASE, fs);
+ rdmsrl(MSR_GS_BASE, gs);
+ rdmsrl(MSR_KERNEL_GS_BASE, shadowgs);
+
+ asm("movq %%cr0, %0": "=r" (cr0));
+ asm("movq %%cr2, %0": "=r" (cr2));
+ asm("movq %%cr3, %0": "=r" (cr3));
+ asm("movq %%cr4, %0": "=r" (cr4));
+
+ printk("FS: %016lx(%04x) GS:%016lx(%04x) knlGS:%016lx\n",
+ fs, fsindex, gs, gsindex, shadowgs);
+ printk("CS: %04x DS: %04x ES: %04x CR0: %016lx\n", cs, ds, es, cr0);
+ printk("CR2: %016lx CR3: %016lx CR4: %016lx\n", cr2, cr3, cr4);
+
+ if (!user_fault)
+ kstack_trace( (void *) regs->rbp );
+}
+
