Make sure to drop the reference taken when looking up the idxd device as part of the compat bind and unbind sysfs interface.
Fixes: 6e7f3ee97bbe ("dmaengine: idxd: move dsa_drv support to compatible mode") Cc: stable@vger.kernel.org # 5.15 Cc: Dave Jiang dave.jiang@intel.com Signed-off-by: Johan Hovold johan@kernel.org --- drivers/dma/idxd/compat.c | 23 +++++++++++++++++++---- 1 file changed, 19 insertions(+), 4 deletions(-)
diff --git a/drivers/dma/idxd/compat.c b/drivers/dma/idxd/compat.c index eff9943f1a42..95b8ef958633 100644 --- a/drivers/dma/idxd/compat.c +++ b/drivers/dma/idxd/compat.c @@ -20,11 +20,16 @@ static ssize_t unbind_store(struct device_driver *drv, const char *buf, size_t c int rc = -ENODEV;
dev = bus_find_device_by_name(bus, NULL, buf); - if (dev && dev->driver) { + if (!dev) + return -ENODEV; + + if (dev->driver) { device_driver_detach(dev); rc = count; }
+ put_device(dev); + return rc; } static DRIVER_ATTR_IGNORE_LOCKDEP(unbind, 0200, NULL, unbind_store); @@ -38,9 +43,12 @@ static ssize_t bind_store(struct device_driver *drv, const char *buf, size_t cou struct idxd_dev *idxd_dev;
dev = bus_find_device_by_name(bus, NULL, buf); - if (!dev || dev->driver || drv != &dsa_drv.drv) + if (!dev) return -ENODEV;
+ if (dev->driver || drv != &dsa_drv.drv) + goto err_put_dev; + idxd_dev = confdev_to_idxd_dev(dev); if (is_idxd_dev(idxd_dev)) { alt_drv = driver_find("idxd", bus); @@ -53,13 +61,20 @@ static ssize_t bind_store(struct device_driver *drv, const char *buf, size_t cou alt_drv = driver_find("user", bus); } if (!alt_drv) - return -ENODEV; + goto err_put_dev;
rc = device_driver_attach(alt_drv, dev); if (rc < 0) - return rc; + goto err_put_dev; + + put_device(dev);
return count; + +err_put_dev: + put_device(dev); + + return rc; } static DRIVER_ATTR_IGNORE_LOCKDEP(bind, 0200, NULL, bind_store);
On 11/17/25 9:12 AM, Johan Hovold wrote:
Make sure to drop the reference taken when looking up the idxd device as part of the compat bind and unbind sysfs interface.
Fixes: 6e7f3ee97bbe ("dmaengine: idxd: move dsa_drv support to compatible mode") Cc: stable@vger.kernel.org # 5.15 Cc: Dave Jiang dave.jiang@intel.com Signed-off-by: Johan Hovold johan@kernel.org
Reviewed-by: Dave Jiang dave.jiang@intel.com> ---
drivers/dma/idxd/compat.c | 23 +++++++++++++++++++---- 1 file changed, 19 insertions(+), 4 deletions(-)
diff --git a/drivers/dma/idxd/compat.c b/drivers/dma/idxd/compat.c index eff9943f1a42..95b8ef958633 100644 --- a/drivers/dma/idxd/compat.c +++ b/drivers/dma/idxd/compat.c @@ -20,11 +20,16 @@ static ssize_t unbind_store(struct device_driver *drv, const char *buf, size_t c int rc = -ENODEV; dev = bus_find_device_by_name(bus, NULL, buf);
- if (dev && dev->driver) {
- if (!dev)
return -ENODEV;- if (dev->driver) { device_driver_detach(dev); rc = count; }
- put_device(dev);
- return rc;
} static DRIVER_ATTR_IGNORE_LOCKDEP(unbind, 0200, NULL, unbind_store); @@ -38,9 +43,12 @@ static ssize_t bind_store(struct device_driver *drv, const char *buf, size_t cou struct idxd_dev *idxd_dev; dev = bus_find_device_by_name(bus, NULL, buf);
- if (!dev || dev->driver || drv != &dsa_drv.drv)
- if (!dev) return -ENODEV;
- if (dev->driver || drv != &dsa_drv.drv)
goto err_put_dev;- idxd_dev = confdev_to_idxd_dev(dev); if (is_idxd_dev(idxd_dev)) { alt_drv = driver_find("idxd", bus);
@@ -53,13 +61,20 @@ static ssize_t bind_store(struct device_driver *drv, const char *buf, size_t cou alt_drv = driver_find("user", bus); } if (!alt_drv)
return -ENODEV;
goto err_put_dev;rc = device_driver_attach(alt_drv, dev); if (rc < 0)
return rc;
goto err_put_dev;- put_device(dev);
return count;
+err_put_dev:
- put_device(dev);
- return rc;
} static DRIVER_ATTR_IGNORE_LOCKDEP(bind, 0200, NULL, bind_store);
On Mon, Nov 17, 2025 at 09:18:39AM -0700, Dave Jiang wrote:
On 11/17/25 9:12 AM, Johan Hovold wrote:
Make sure to drop the reference taken when looking up the idxd device as part of the compat bind and unbind sysfs interface.
Fixes: 6e7f3ee97bbe ("dmaengine: idxd: move dsa_drv support to compatible mode") Cc: stable@vger.kernel.org # 5.15 Cc: Dave Jiang dave.jiang@intel.com Signed-off-by: Johan Hovold johan@kernel.org
Reviewed-by: Dave Jiang dave.jiang@intel.com> ---
Thanks for reviewing.
Note that something happened here with the end of your tag. Hopefully Vinod can fix that up when applying.
Johan
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