labs/templates: Update 7-kvm-vmm skel

Update assignment 7: kvm vmm skel to fix several build errors.

* Add `-Iinclude/` to CFLAGS
* Fix Makefile rules for the guests
* Add `#endif`s to the header files
* Halt at the end of the 32 bits guest
* Fix structure names in vmm.c

Signed-off-by: Stefan Jumarea <[email protected]>

Author: StefanJum

tools/labs/templates/assignments/7-kvm-vmm/skel/Makefile

@@ -1,24 +1,25 @@
-CFLAGS = -Wall -Wextra -O2
+CFLAGS = -g -Wall -Wextra -O0 -Iinclude/
 
-run64: kvm-hello-world
+.PHONY: run
+run: kvm-hello-world
 	./kvm-hello-world
 
-kvm-hello-world: vmm.o payload.o virtual_machine.o virtual_cpu.o
+kvm-hello-world: vmm.o payload.o
 	$(CC) $^ -o $@
 
-payload.o: payload.ld guest64.img.o guest16.o
-	$(LD) -T $< -o $@
+payload.o: payload.ld guest_16_bits/guest16.o guest64.img.o
+	$(LD) -r -T $< -o $@
 
-guest64.o: guest_code.c 
+guest64.o: guest_32_bits/guest_code.c
 	$(CC) $(CFLAGS) -m64 -ffreestanding -fno-pic -c -o $@ $^
 
 guest64.img: guest64.o
-	$(LD) -T guest.ld $^ -o $@
+	$(LD) -T guest_32_bits/guest.ld $^ -o $@
 
 %.img.o: %.img
 	$(LD) -b binary -r $^ -o $@
 
 .PHONY: clean
 clean:
-	$(RM) kvm-hello-world kvm-hello-world.o payload.o \
-		*.o *.img
+	$(RM) kvm-hello-world vmm.o payload.o guest_16_bits/guest16.o \
+		guest64.o guest64.img guest64.img.o

tools/labs/templates/assignments/7-kvm-vmm/skel/guest_16_bits/guest16.s

@@ -1,7 +1,7 @@
         .code16
-        .global code16, code16_end
+        .global guest16, guest16_end
 guest16:
         movw $42, %ax
         movw %ax, 0x400
         hlt
-guest16_end:
+guest16_end:

tools/labs/templates/assignments/7-kvm-vmm/skel/guest_16_bits/guest.ld tools/labs/templates/assignments/7-kvm-vmm/skel/guest_32_bits/guest.ld

@@ -1,3 +1,4 @@
+#include <stdint.h>
 #include "device.h"
 
 // Phys addr memory layout:
@@ -48,6 +49,7 @@ void
 __attribute__((noreturn))
 __attribute__((section(".start")))
 _start(void) {
+	const char *p;
 
 	for (p = "Hello, world!\n"; *p; ++p)
 		outb(0xE9, *p);
@@ -57,4 +59,5 @@ _start(void) {
     /* TODO: Using the paravirtualized driver we have written for SIMVIRTIO, send
      "Ana are mere!\n" */
 
+	asm("hlt" : /* empty */ : "a" (42) : "memory");
 }

tools/labs/templates/assignments/7-kvm-vmm/skel/guest_32_bits/guest_code.c

@@ -61,4 +61,6 @@
 typedef struct vcpu {
 	int fd;
 	struct kvm_run *kvm_run;
-} virtual_cpu;
+} virtual_cpu;
+
+#endif

tools/labs/templates/assignments/7-kvm-vmm/skel/include/vcpu.h

@@ -6,4 +6,6 @@ typedef struct vm {
 	int sys_fd;
 	int fd;
 	char *mem;
-} virtual_machine;
+} virtual_machine;
+
+#endif

tools/labs/templates/assignments/7-kvm-vmm/skel/include/vm.h

@@ -2,12 +2,12 @@ SECTIONS
 {
         .payload16 0 : {
                 guest16 = .;
-                guest16.o(.text)
+                guest_16_bits/guest16.o(.text)
                 guest16_end = .;
         }
         .payload64 0 : AT(LOADADDR(.payload16)+SIZEOF(.payload16)) {
                 guest64 = .;
                 guest64.img.o
                 guest64_end = .;
         }
-} 
+} 

tools/labs/templates/assignments/7-kvm-vmm/skel/payload.ld

@@ -18,17 +18,19 @@ int main(int argc, char **argv) {
 	UNUSED_PARAMETER(argv);
     struct vm virtual_machine;
     struct vcpu virtual_cpu;
+    struct kvm_regs regs;
+    uint16_t memval;
 
     /* TODO: Initialize the VM. We will use 0x100000 bytes for the memory */
     /* TODO: Initialize the VCPU */
-    /* TODO: Setup real mode. We will use guest_16_bits to test this.
+    /* TODO: Setup real mode. We will use guest_16_bits to test this. */
     /* TODO: IF real mode works all right. We can try to set up long mode*/
 
     for (;;) {
         /* TODO: Run the VCPU with KVM_RUN */
 
         /* TODO: Handle VMEXITs */
-        switch (vcpu->kvm_run->exit_reason) {
+        switch (virtual_cpu.kvm_run->exit_reason) {
             case KVM_EXIT_HLT: {goto check;}
             case KVM_EXIT_MMIO: {
                 /* TODO: Handle MMIO read/write. Data is available in the shared memory at 
@@ -42,13 +44,13 @@ int main(int argc, char **argv) {
 
         fprintf(stderr,	"\nGot exit_reason %d,"
                     " expected KVM_EXIT_HLT (%d)\n",
-                    vcpu->kvm_run->exit_reason, KVM_EXIT_HLT);
+                    virtual_cpu.kvm_run->exit_reason, KVM_EXIT_HLT);
         exit(1);
     }
 
     /* We verify that the guest code ran accordingly */
     check:
-    if (ioctl(vcpu->fd, KVM_GET_REGS, &regs) < 0) {
+    if (ioctl(virtual_cpu.fd, KVM_GET_REGS, &regs) < 0) {
 		perror("KVM_GET_REGS");
 		exit(1);
 	}
@@ -60,7 +62,7 @@ int main(int argc, char **argv) {
 	}
 
     /* Verify that the guest has written 42 at 0x400 */
-	memcpy(&memval, &vm->mem[0x400], sz);
+	memcpy(&memval, &virtual_machine.mem[0x400], sizeof(uint16_t));
 	if (memval != 42) {
 		printf("Wrong result: memory at 0x400 is %lld\n",
 		       (unsigned long long)memval);
@@ -69,4 +71,4 @@ int main(int argc, char **argv) {
 
 	printf("%s\n", "Finished vmm");
 	return 0;
-} 
+}