6.6-stable review patch. If anyone has any objections, please let me know.
------------------
From: Maurizio Lombardi <mlombard@xxxxxxxxxx>
[ Upstream commit 26bc0a81f64ce00fc4342c38eeb2eddaad084dd2 ]
nvme_dev_disable() modifies the dev->online_queues field, therefore
nvme_pci_update_nr_queues() should avoid racing against it, otherwise
we could end up passing invalid values to blk_mq_update_nr_hw_queues().
WARNING: CPU: 39 PID: 61303 at drivers/pci/msi/api.c:347
pci_irq_get_affinity+0x187/0x210
Workqueue: nvme-reset-wq nvme_reset_work [nvme]
RIP: 0010:pci_irq_get_affinity+0x187/0x210
Call Trace:
<TASK>
? blk_mq_pci_map_queues+0x87/0x3c0
? pci_irq_get_affinity+0x187/0x210
blk_mq_pci_map_queues+0x87/0x3c0
nvme_pci_map_queues+0x189/0x460 [nvme]
blk_mq_update_nr_hw_queues+0x2a/0x40
nvme_reset_work+0x1be/0x2a0 [nvme]
Fix the bug by locking the shutdown_lock mutex before using
dev->online_queues. Give up if nvme_dev_disable() is running or if
it has been executed already.
Fixes: 949928c1c731 ("NVMe: Fix possible queue use after freed")
Tested-by: Yi Zhang <yi.zhang@xxxxxxxxxx>
Reviewed-by: Christoph Hellwig <hch@xxxxxx>
Signed-off-by: Maurizio Lombardi <mlombard@xxxxxxxxxx>
Signed-off-by: Keith Busch <kbusch@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/nvme/host/pci.c | 19 ++++++++++++++++---
1 file changed, 16 insertions(+), 3 deletions(-)
diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
index 61c9b175e035f..b701969cf1c2a 100644
--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c
@@ -2469,17 +2469,29 @@ static unsigned int nvme_pci_nr_maps(struct nvme_dev *dev)
return 1;
}
-static void nvme_pci_update_nr_queues(struct nvme_dev *dev)
+static bool nvme_pci_update_nr_queues(struct nvme_dev *dev)
{
if (!dev->ctrl.tagset) {
nvme_alloc_io_tag_set(&dev->ctrl, &dev->tagset, &nvme_mq_ops,
nvme_pci_nr_maps(dev), sizeof(struct nvme_iod));
- return;
+ return true;
+ }
+
+ /* Give up if we are racing with nvme_dev_disable() */
+ if (!mutex_trylock(&dev->shutdown_lock))
+ return false;
+
+ /* Check if nvme_dev_disable() has been executed already */
+ if (!dev->online_queues) {
+ mutex_unlock(&dev->shutdown_lock);
+ return false;
}
blk_mq_update_nr_hw_queues(&dev->tagset, dev->online_queues - 1);
/* free previously allocated queues that are no longer usable */
nvme_free_queues(dev, dev->online_queues);
+ mutex_unlock(&dev->shutdown_lock);
+ return true;
}
static int nvme_pci_enable(struct nvme_dev *dev)
@@ -2760,7 +2772,8 @@ static void nvme_reset_work(struct work_struct *work)
nvme_dbbuf_set(dev);
nvme_unquiesce_io_queues(&dev->ctrl);
nvme_wait_freeze(&dev->ctrl);
- nvme_pci_update_nr_queues(dev);
+ if (!nvme_pci_update_nr_queues(dev))
+ goto out;
nvme_unfreeze(&dev->ctrl);
} else {
dev_warn(dev->ctrl.device, "IO queues lost\n");
--
2.43.0
