diff --git a/kernel-src/include/kernel/dpc.h b/kernel-src/include/kernel/dpc.h
index a7e6a879..1d14bdbe 100644
--- a/kernel-src/include/kernel/dpc.h
+++ b/kernel-src/include/kernel/dpc.h
@@ -15,7 +15,8 @@ typedef struct _dpc_t {
 	dpcarg_t arg;
 } dpc_t;
 
-void dpc_enqueue(dpc_t *dpc, dpcfn_t, dpcarg_t);
+void dpc_prepare(dpc_t *dpc, dpcfn_t fn);
+void dpc_enqueue(dpc_t *dpc, dpcarg_t arg);
 void dpc_dequeue(dpc_t *dpc);
 void dpc_init();
 
diff --git a/kernel-src/include/kernel/timer.h b/kernel-src/include/kernel/timer.h
index 46cebc68..77a388e6 100644
--- a/kernel-src/include/kernel/timer.h
+++ b/kernel-src/include/kernel/timer.h
@@ -11,9 +11,8 @@ typedef struct timerentry_t {
 	struct timerentry_t *next;
 	time_t absolutetick;
 	time_t repeatus;
-	dpcfn_t fn;
-	dpcarg_t arg;
 	dpc_t dpc;
+	dpcarg_t arg;
 	bool fired;
 } timerentry_t;
 
diff --git a/kernel-src/io/block/ahci.c b/kernel-src/io/block/ahci.c
index f66aed5f..02fa12c1 100644
--- a/kernel-src/io/block/ahci.c
+++ b/kernel-src/io/block/ahci.c
@@ -204,7 +204,7 @@ void ahci_dpc(context_t *, dpcarg_t arg) {
 	}
 
 	// notify waiters about command completion
-	while (port_data->waiters[port_data->command_waiting] && 
+	while (port_data->waiters[port_data->command_waiting] &&
 	(port_data->ahci->ports[port].ci & (1 << port_data->command_waiting)) == 0) {
 		thread_t *thread = port_data->waiters[port_data->command_waiting];
 		port_data->waiters[port_data->command_waiting] = NULL;
@@ -230,7 +230,7 @@ void ahci_isr(isr_t *isr, context_t *) {
 		if (ahci->port_data[i] == NULL)
 			continue;
 
-		dpc_enqueue(&ahci->port_data[i]->dpc, ahci_dpc, ahci->port_data[i]);
+		dpc_enqueue(&ahci->port_data[i]->dpc, ahci->port_data[i]);
 
 		ports_pending &= ~(1 << i);
 		ahci->ports[i].is = ahci->ports[i].is;
@@ -413,7 +413,7 @@ static void init_port(ahci_t *ahci, int port) {
 		return;
 	}
 
-	ahci->port_data[port]->sector_count = (uint64_t)identify->lba48_size[0] | ((uint64_t)identify->lba48_size[1] << 16) | 
+	ahci->port_data[port]->sector_count = (uint64_t)identify->lba48_size[0] | ((uint64_t)identify->lba48_size[1] << 16) |
 				((uint64_t)identify->lba48_size[2] << 32) | ((uint64_t)identify->lba48_size[3] << 48);
 
 	printf("ahci%dp%d: ATA drive with %lu sectors\n", ahci->id, port, ahci->port_data[port]->sector_count);
@@ -549,7 +549,6 @@ static void init_controller(pcienum_t *pci_enum) {
 			continue;
 		}
 
-
 		// program command list base
 		void *cmd_ptr = (void *)((uintptr_t)command_slot_mem + command_slot_offset);
 		memset(MAKE_HHDM(cmd_ptr), 0, 1024);
@@ -609,6 +608,7 @@ static void init_controller(pcienum_t *pci_enum) {
 		port_data->command_list = MAKE_HHDM(cmd_ptr);
 		SPINLOCK_INIT(port_data->command_lock);
 		SEMAPHORE_INIT(&port_data->command_semaphore, ahci->command_slot_count);
+		dpc_prepare(&port_data->dpc, ahci_dpc);
 
 		ahci->port_data[i] = port_data;
 	}
diff --git a/kernel-src/io/block/nvme.c b/kernel-src/io/block/nvme.c
index f545c81f..7225ec79 100644
--- a/kernel-src/io/block/nvme.c
+++ b/kernel-src/io/block/nvme.c
@@ -299,7 +299,7 @@ static void nvme_dpc(context_t *, dpcarg_t arg) {
 
 static void nvme_irq(isr_t *isr, context_t *context) {
 	queuepair_t *pair = isr->priv;
-	dpc_enqueue(&pair->dpc, nvme_dpc, pair);
+	dpc_enqueue(&pair->dpc, pair);
 }
 
 static isr_t *msixnewisrforqueue(queuepair_t *queuepair) {
@@ -458,6 +458,7 @@ static int createiosubqueue(nvmecontroller_t *controller, queuedesc_t *desc, siz
 }
 
 static void newioqueuepair(nvmecontroller_t *controller, queuepair_t *pair, int id) {
+	dpc_prepare(&pair->dpc, nvme_dpc);
 	__assert(createiocompqueue(controller, &pair->completion, QUEUEPAIR_ENTRY_COUNT, id, id, 0) == 0);
 	__assert(createiosubqueue(controller, &pair->submission, QUEUEPAIR_ENTRY_COUNT, id, id, 0) == 0);
 	pair->controller = controller;
@@ -813,6 +814,8 @@ static void initcontroller(pcienum_t *e) {
 	controller->adminqueue.completion.doorbell = GET_DOORBELL(controller->bar0, 0, 1, controller->dbstride);
 	controller->adminqueue.completion.phase = 1;
 
+	dpc_prepare(&controller->adminqueue.dpc, nvme_dpc);
+
 	SPINLOCK_INIT(controller->adminqueue.lock);
 	SEMAPHORE_INIT(&controller->adminqueue.entrysem, QUEUEPAIR_ENTRY_COUNT);
 
diff --git a/kernel-src/io/block/vioblk.c b/kernel-src/io/block/vioblk.c
index 63799169..da0f5b02 100644
--- a/kernel-src/io/block/vioblk.c
+++ b/kernel-src/io/block/vioblk.c
@@ -54,7 +54,7 @@ static void vioblk_dpc(context_t *context, dpcarg_t arg) {
 
 static void vioblk_irq(isr_t *isr, context_t *context) {
 	vioblkdev_t *blkdev = isr->priv;
-	dpc_enqueue(&blkdev->queuedpc, vioblk_dpc, blkdev);
+	dpc_enqueue(&blkdev->queuedpc, blkdev);
 }
 
 // driver and device are physical addresses
@@ -176,6 +176,7 @@ int vioblk_newdevice(viodevice_t *viodevice) {
 	// initialize device object
 	vioblkdev_t *blkdev = alloc(sizeof(vioblkdev_t));
 	__assert(blkdev);
+	dpc_prepare(&blkdev->queuedpc, vioblk_dpc);
 
 	static int id = 0;
 	volatile blkdevconfig_t *blkconfig = viodevice->devconfig;
diff --git a/kernel-src/io/net/loopback.c b/kernel-src/io/net/loopback.c
index 7086170f..3def9a03 100644
--- a/kernel-src/io/net/loopback.c
+++ b/kernel-src/io/net/loopback.c
@@ -43,7 +43,8 @@ static int loopback_sendpacket(netdev_t *netdev, netdesc_t desc, mac_t targetmac
 	memcpy(desc.address, &ethframe, sizeof(ethframe_t));
 
 	dpc_t dpc = {0};
-	dpc_enqueue(&dpc, rx_dpc, desc.address);
+	dpc_prepare(&dpc, rx_dpc);
+	dpc_enqueue(&dpc, desc.address);
 
 	return 0;
 }
diff --git a/kernel-src/io/net/rtl8169.c b/kernel-src/io/net/rtl8169.c
index 726276e8..2d0900c9 100644
--- a/kernel-src/io/net/rtl8169.c
+++ b/kernel-src/io/net/rtl8169.c
@@ -152,10 +152,10 @@ static void rtl8169_isr(isr_t *self, context_t *) {
 		outw(dev->bar.address + REGISTER_IRQ_STATUS, status);
 
 		if (status & (REGISTER_IRQ_STATUS_TX_OK | REGISTER_IRQ_STATUS_TX_ERROR))
-			dpc_enqueue(&dev->tx_dpc, rtl8169_dpc_tx, dev);
+			dpc_enqueue(&dev->tx_dpc, dev);
 
 		if (status & (REGISTER_IRQ_STATUS_RX_OK | REGISTER_IRQ_STATUS_RX_ERROR))
-			dpc_enqueue(&dev->rx_dpc, rtl8169_dpc_rx, dev);
+			dpc_enqueue(&dev->rx_dpc, dev);
 
 		status = inw(dev->bar.address + REGISTER_IRQ_STATUS);
 	}
@@ -311,7 +311,7 @@ static void init_controller(pcienum_t *pci_enum) {
 
 	outb(pci_bar.address + REGISTER_COMMAND, REGISTER_COMMAND_TX_ENABLE);
 	outd(pci_bar.address + REGISTER_TX_CONFIG, REGISTER_TX_CONFIG_DMA_BURST_UNLIMITED | REGISTER_TX_CONFIG_IFG_NORMAL);
- 
+
 	outw(pci_bar.address + REGISTER_RX_MAX_SIZE, 1518);
 	// 128 * 0xc, enough for an ethernet MTU (while 0xb would be enough, the datasheet says that it must be larger than the max size)
 	outb(pci_bar.address + REGISTER_TX_MAX_SIZE, 0xc);
@@ -337,6 +337,9 @@ static void init_controller(pcienum_t *pci_enum) {
 	SEMAPHORE_INIT(&netdev->tx_semaphore, TX_DESCRIPTOR_COUNT);
 	SPINLOCK_INIT(netdev->tx_lock);
 
+	dpc_prepare(&netdev->tx_dpc, rtl8169_dpc_tx);
+	dpc_prepare(&netdev->rx_dpc, rtl8169_dpc_rx);
+
 	isr->priv = netdev;
 
 	char name[10];
diff --git a/kernel-src/io/net/vionet.c b/kernel-src/io/net/vionet.c
index 1d45d05e..9d10c277 100644
--- a/kernel-src/io/net/vionet.c
+++ b/kernel-src/io/net/vionet.c
@@ -54,7 +54,7 @@ static void rx_dpc(context_t *context, dpcarg_t arg) {
 
 static void rx_irq(isr_t *isr, context_t *context) {
 	vionetdev_t *netdev = isr->priv;
-	dpc_enqueue(&netdev->rxdpc, rx_dpc, netdev);
+	dpc_enqueue(&netdev->rxdpc, netdev);
 }
 
 static void tx_dpc(context_t *context, dpcarg_t arg) {
@@ -75,7 +75,7 @@ static void tx_dpc(context_t *context, dpcarg_t arg) {
 
 static void tx_irq(isr_t *isr, context_t *context) {
 	vionetdev_t *netdev = isr->priv;
-	dpc_enqueue(&netdev->txdpc, tx_dpc, netdev);
+	dpc_enqueue(&netdev->txdpc, netdev);
 }
 
 #define PREFIX_SIZE (sizeof(ethframe_t) + sizeof(vioframe_t))
@@ -178,6 +178,8 @@ int vionet_newdevice(viodevice_t *viodevice) {
 	netdev->netdev.allocdesc = vionet_allocdesc;
 	netdev->netdev.freedesc = vionet_freedesc;
 	__assert(hashtable_init(&netdev->netdev.arpcache, 30) == 0);
+	dpc_prepare(&netdev->rxdpc, rx_dpc);
+	dpc_prepare(&netdev->txdpc, tx_dpc);
 
 	// initialize queues
 	size_t rxsize = min(QUEUE_MAX_SIZE, virtio_queuesize(viodevice, 0));
diff --git a/kernel-src/sys/dpc.c b/kernel-src/sys/dpc.c
index cae40170..a7701074 100644
--- a/kernel-src/sys/dpc.c
+++ b/kernel-src/sys/dpc.c
@@ -39,13 +39,19 @@ static void isrfn(isr_t *self, context_t *context) {
 	}
 }
 
-void dpc_enqueue(dpc_t *dpc, dpcfn_t fn, dpcarg_t arg) {
+void dpc_prepare(dpc_t *dpc, dpcfn_t fn) {
+	dpc->fn = fn;
+	dpc->enqueued = false;
+	dpc->next = NULL;
+	dpc->prev = NULL;
+}
+
+void dpc_enqueue(dpc_t *dpc, dpcarg_t arg) {
 	bool entrystate = interrupt_set(false);
 
 	if (dpc->enqueued)
 		goto cleanup;
 
-	dpc->fn = fn;
 	dpc->arg = arg;
 	dpc->enqueued = true;
 	insert(dpc);
diff --git a/kernel-src/sys/scheduler/scheduler.c b/kernel-src/sys/scheduler/scheduler.c
index e34027b4..3e4b4e6d 100644
--- a/kernel-src/sys/scheduler/scheduler.c
+++ b/kernel-src/sys/scheduler/scheduler.c
@@ -22,7 +22,7 @@ static __attribute__((noreturn)) void switch_thread(thread_t *thread) {
 	thread_t* current = current_thread();
 
 	sched_thread_running_callback(thread);
-	
+
 	current_cpu()->thread = thread;
 
 	if(current == NULL || thread->vmmctx != current->vmmctx)
@@ -230,7 +230,7 @@ static void dopreempt() {
 	switch_thread(next);
 }
 
-static void preempt_dpc(context_t *context, dpcarg_t arg) {
+static void sched_reschedule_dpc(context_t *context, dpcarg_t arg) {
 	thread_t* current = current_thread();
 	interrupt_set(false);
 
@@ -250,18 +250,18 @@ static void preempt_dpc(context_t *context, dpcarg_t arg) {
 
 // IPL_DPC
 static void reschedule_timer_dpc(context_t *context, dpcarg_t arg) {
-	dpc_enqueue(&current_cpu()->reschedule_dpc, preempt_dpc, NULL);
+	dpc_enqueue(&current_cpu()->reschedule_dpc, NULL);
 }
 
 // IPL_MAX
 static void reschedule_ipi(isr_t *, context_t *) {
-	dpc_enqueue(&current_cpu()->reschedule_dpc, preempt_dpc, NULL);
+	dpc_enqueue(&current_cpu()->reschedule_dpc, NULL);
 }
 
 void sched_preempt_cpu(cpu_t *cpu) {
 	long ipl = interrupt_raiseipl(IPL_DPC);
 	if (cpu == current_cpu()) {
-		dpc_enqueue(&cpu->reschedule_dpc, preempt_dpc, NULL);
+		dpc_enqueue(&cpu->reschedule_dpc, NULL);
 	} else {
 		arch_smp_send_ipi(cpu, cpu->reschedule_isr, ARCH_SMP_IPI_TARGET, false);
 	}
@@ -347,6 +347,7 @@ void sched_load_balancer(context_t *, dpcarg_t);
 void sched_ap_entry() {
 	SPINLOCK_INIT(current_cpu()->sched_lock);
 
+	dpc_prepare(&current_cpu()->reschedule_dpc, sched_reschedule_dpc);
 	set_up_bitmaps();
 
 	current_cpu()->schedulerstack = vmm_map(NULL, SCHEDULER_STACK_SIZE, VMM_FLAGS_ALLOCATE, ARCH_MMU_FLAGS_READ | ARCH_MMU_FLAGS_WRITE | ARCH_MMU_FLAGS_NOEXEC, NULL);
@@ -374,7 +375,8 @@ void sched_init() {
 
 	SPINLOCK_INIT(current_cpu()->sched_lock);
 	SPINLOCK_INIT(sched_idle_cpu_bitmap_lock);
-	
+
+	dpc_prepare(&current_cpu()->reschedule_dpc, sched_reschedule_dpc);
 	set_up_bitmaps();
 
 	__assert(bitmap_init(&sched_idle_cpu_bitmap, arch_smp_get_cpu_count()) == 0);
diff --git a/kernel-src/sys/timer.c b/kernel-src/sys/timer.c
index a7ecbe2f..e0d4617d 100644
--- a/kernel-src/sys/timer.c
+++ b/kernel-src/sys/timer.c
@@ -60,7 +60,7 @@ static void timercheck(timer_t *timer) {
 		else
 			entry->fired = true;
 
-		dpc_enqueue(&entry->dpc, entry->fn, entry->arg);
+		dpc_enqueue(&entry->dpc, entry->arg);
 	}
 }
 
@@ -87,7 +87,7 @@ void timer_isr(timer_t *timer, context_t *context) {
 	else
 		oldentry->fired = true;
 
-	dpc_enqueue(&oldentry->dpc, oldentry->fn, oldentry->arg);
+	dpc_enqueue(&oldentry->dpc, oldentry->arg);
 
 	leave:
 	timercheck(timer);
@@ -143,9 +143,9 @@ void timer_insert(timer_t *timer, timerentry_t *entry, dpcfn_t fn, dpcarg_t arg,
 
 	memset(entry, 0, sizeof(timerentry_t));
 	entry->repeatus = repeating ? us : 0;
-	entry->fn = fn;
-	entry->arg = arg;
 	entry->fired = false;
+	entry->arg = arg;
+	dpc_prepare(&entry->dpc, fn);
 	insert(timer, entry, us);
 
 	if (timer->running) {