Commit e71084af authored by Clemens Ladisch's avatar Clemens Ladisch Committed by Stefan Richter
Browse files

firewire: core: fix card->reset_jiffies overflow 



On a 32-bit machine with, e.g., HZ=1000, jiffies will overflow after
about 50 days, so if there are between 25 and 50 days between bus
resets, the card->reset_jiffies comparisons can get wrong results.

To fix this, ensure that this timestamp always uses 64 bits.

Signed-off-by: default avatarClemens Ladisch <clemens@ladisch.de>
Signed-off-by: default avatar"Stefan Richter" <stefanr@s5r6.in-berlin.de>
parent dbc9880f

drivers/firewire/core-card.c

+3 −2
Original line number Diff line number Diff line
@@ -233,7 +233,7 @@ static void br_work(struct work_struct *work) 


	/* Delay for 2s after last reset per IEEE 1394 clause 8.2.1. */

	if (card->reset_jiffies != 0 &&

	    time_is_after_jiffies(card->reset_jiffies + 2 * HZ)) {

	    time_before64(get_jiffies_64(), card->reset_jiffies + 2 * HZ)) {

		if (!schedule_delayed_work(&card->br_work, 2 * HZ))

			fw_card_put(card);

		return;
@@ -316,7 +316,8 @@ static void bm_work(struct work_struct *work) 
	irm_id   = card->irm_node->node_id;

	local_id = card->local_node->node_id;



	grace = time_after(jiffies, card->reset_jiffies + DIV_ROUND_UP(HZ, 8));

	grace = time_after64(get_jiffies_64(),

			     card->reset_jiffies + DIV_ROUND_UP(HZ, 8));



	if ((is_next_generation(generation, card->bm_generation) &&

	     !card->bm_abdicate) ||

drivers/firewire/core-cdev.c

+2 −1
Original line number Diff line number Diff line
@@ -1205,7 +1205,8 @@ static void iso_resource_work(struct work_struct *work) 
	todo = r->todo;

	/* Allow 1000ms grace period for other reallocations. */

	if (todo == ISO_RES_ALLOC &&

	    time_is_after_jiffies(client->device->card->reset_jiffies + HZ)) {

	    time_before64(get_jiffies_64(),

			  client->device->card->reset_jiffies + HZ)) {

		schedule_iso_resource(r, DIV_ROUND_UP(HZ, 3));

		skip = true;

	} else {

drivers/firewire/core-device.c

+2 −1
Original line number Diff line number Diff line
@@ -747,7 +747,8 @@ static void fw_device_shutdown(struct work_struct *work) 
		container_of(work, struct fw_device, work.work);

	int minor = MINOR(device->device.devt);



	if (time_is_after_jiffies(device->card->reset_jiffies + SHUTDOWN_DELAY)

	if (time_before64(get_jiffies_64(),

			  device->card->reset_jiffies + SHUTDOWN_DELAY)

	    && !list_empty(&device->card->link)) {

		schedule_delayed_work(&device->work, SHUTDOWN_DELAY);

		return;

drivers/firewire/core-topology.c

+1 −1
Original line number Diff line number Diff line
@@ -545,7 +545,7 @@ void fw_core_handle_bus_reset(struct fw_card *card, int node_id, int generation, 
	 */

	smp_wmb();

	card->generation = generation;

	card->reset_jiffies = jiffies;

	card->reset_jiffies = get_jiffies_64();

	card->bm_node_id  = 0xffff;

	card->bm_abdicate = bm_abdicate;

	fw_schedule_bm_work(card, 0);

include/linux/firewire.h

+1 −1
Original line number Diff line number Diff line
@@ -89,7 +89,7 @@ struct fw_card { 
	int current_tlabel;

	u64 tlabel_mask;

	struct list_head transaction_list;

	unsigned long reset_jiffies;

	u64 reset_jiffies;



	u32 split_timeout_hi;

	u32 split_timeout_lo;

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