[PATCH v2 01/10] dmaengine: idxd: Fix lockdep warnings when calling idxd_device_config()

From: Vinicius Costa Gomes
Date: Thu Aug 21 2025 - 19:00:37 EST


Move the check for IDXD_FLAG_CONFIGURABLE and the locking to "inside"
idxd_device_config(), as this is common to all callers, and the one
that wasn't holding the lock was an error (that was causing the
lockdep warning).

Suggested-by: Dave Jiang <dave.jiang@xxxxxxxxx>
Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@xxxxxxxxx>
---
drivers/dma/idxd/device.c | 17 +++++++----------
drivers/dma/idxd/init.c | 10 ++++------
2 files changed, 11 insertions(+), 16 deletions(-)

diff --git a/drivers/dma/idxd/device.c b/drivers/dma/idxd/device.c
index 5cf419fe6b46..ac41889e4fe1 100644
--- a/drivers/dma/idxd/device.c
+++ b/drivers/dma/idxd/device.c
@@ -1107,7 +1107,11 @@ int idxd_device_config(struct idxd_device *idxd)
{
int rc;

- lockdep_assert_held(&idxd->dev_lock);
+ guard(spinlock)(&idxd->dev_lock);
+
+ if (!test_bit(IDXD_FLAG_CONFIGURABLE, &idxd->flags))
+ return 0;
+
rc = idxd_wqs_setup(idxd);
if (rc < 0)
return rc;
@@ -1434,11 +1438,7 @@ int idxd_drv_enable_wq(struct idxd_wq *wq)
}
}

- rc = 0;
- spin_lock(&idxd->dev_lock);
- if (test_bit(IDXD_FLAG_CONFIGURABLE, &idxd->flags))
- rc = idxd_device_config(idxd);
- spin_unlock(&idxd->dev_lock);
+ rc = idxd_device_config(idxd);
if (rc < 0) {
dev_dbg(dev, "Writing wq %d config failed: %d\n", wq->id, rc);
goto err;
@@ -1534,10 +1534,7 @@ int idxd_device_drv_probe(struct idxd_dev *idxd_dev)
}

/* Device configuration */
- spin_lock(&idxd->dev_lock);
- if (test_bit(IDXD_FLAG_CONFIGURABLE, &idxd->flags))
- rc = idxd_device_config(idxd);
- spin_unlock(&idxd->dev_lock);
+ rc = idxd_device_config(idxd);
if (rc < 0)
return -ENXIO;

diff --git a/drivers/dma/idxd/init.c b/drivers/dma/idxd/init.c
index f98aa41fa42e..c25bd0595561 100644
--- a/drivers/dma/idxd/init.c
+++ b/drivers/dma/idxd/init.c
@@ -1092,12 +1092,10 @@ static void idxd_reset_done(struct pci_dev *pdev)
idxd_device_config_restore(idxd, idxd->idxd_saved);

/* Re-configure IDXD device if allowed. */
- if (test_bit(IDXD_FLAG_CONFIGURABLE, &idxd->flags)) {
- rc = idxd_device_config(idxd);
- if (rc < 0) {
- dev_err(dev, "HALT: %s config fails\n", idxd_name);
- goto out;
- }
+ rc = idxd_device_config(idxd);
+ if (rc < 0) {
+ dev_err(dev, "HALT: %s config fails\n", idxd_name);
+ goto out;
}

/* Bind IDXD device to driver. */

--
2.50.1