[PATCH v5 3/4] virtio_vop: don't kfree device on register failure
From: weiping zhang <hidden>
Date: 2017-12-21 12:40:43
Subsystem:
char and misc drivers, the rest · Maintainers:
Arnd Bergmann, Greg Kroah-Hartman, Linus Torvalds
As mentioned at drivers/base/core.c: /* * NOTE: _Never_ directly free @dev after calling this function, even * if it returned an error! Always use put_device() to give up the * reference initialized in this function instead. */ so we don't free vdev until vdev->vdev.dev.release be called. Signed-off-by: weiping zhang <redacted> Reviewed-by: Cornelia Huck <cohuck@redhat.com> --- drivers/misc/mic/vop/vop_main.c | 20 +++++++++++++------- 1 file changed, 13 insertions(+), 7 deletions(-)
diff --git a/drivers/misc/mic/vop/vop_main.c b/drivers/misc/mic/vop/vop_main.c
index a341938..3633202 100644
--- a/drivers/misc/mic/vop/vop_main.c
+++ b/drivers/misc/mic/vop/vop_main.c@@ -452,10 +452,12 @@ static irqreturn_t vop_virtio_intr_handler(int irq, void *data) static void vop_virtio_release_dev(struct device *_d) { - /* - * No need for a release method similar to virtio PCI. - * Provide an empty one to avoid getting a warning from core. - */ + struct virtio_device *vdev = + container_of(_d, struct virtio_device, dev); + struct _vop_vdev *vop_vdev = + container_of(vdev, struct _vop_vdev, vdev); + + kfree(vop_vdev); } /*
@@ -466,7 +468,7 @@ static int _vop_add_device(struct mic_device_desc __iomem *d, unsigned int offset, struct vop_device *vpdev, int dnode) { - struct _vop_vdev *vdev; + struct _vop_vdev *vdev, *reg_dev = NULL; int ret; u8 type = ioread8(&d->type);
@@ -497,6 +499,7 @@ static int _vop_add_device(struct mic_device_desc __iomem *d, vdev->c2h_vdev_db = ioread8(&vdev->dc->c2h_vdev_db); ret = register_virtio_device(&vdev->vdev); + reg_dev = vdev; if (ret) { dev_err(_vop_dev(vdev), "Failed to register vop device %u type %u\n",
@@ -512,7 +515,10 @@ static int _vop_add_device(struct mic_device_desc __iomem *d, free_irq: vpdev->hw_ops->free_irq(vpdev, vdev->virtio_cookie, vdev); kfree: - kfree(vdev); + if (reg_dev) + put_device(&vdev->vdev.dev); + else + kfree(vdev); return ret; }
@@ -568,7 +574,7 @@ static int _vop_remove_device(struct mic_device_desc __iomem *d, iowrite8(-1, &dc->h2c_vdev_db); if (status & VIRTIO_CONFIG_S_DRIVER_OK) wait_for_completion(&vdev->reset_done); - kfree(vdev); + put_device(&vdev->vdev.dev); iowrite8(1, &dc->guest_ack); dev_dbg(&vpdev->dev, "%s %d guest_ack %d\n", __func__, __LINE__, ioread8(&dc->guest_ack));
--
2.9.4