From: Yuho Choi Date: Mon, 25 May 2026 14:15:50 +0000 (-0400) Subject: dmaengine: idxd: fix fdev setup failure cleanup in idxd_cdev_open() X-Git-Tag: v7.2-rc6~8^2~1 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=ee1d7274102285d78a53161fc705a8d8cd40b066;p=thirdparty%2Flinux.git dmaengine: idxd: fix fdev setup failure cleanup in idxd_cdev_open() The failed_dev_add and failed_dev_name paths drop the file-device reference while wq->wq_lock is still held. If put_device(fdev) drops the last reference, idxd_file_dev_release() runs synchronously and tries to take wq->wq_lock again, deadlocking. Those paths also fall through into the later ctx cleanup labels even though idxd_file_dev_release() owns that cleanup and frees ctx. This can make idxd_xa_pasid_remove(ctx) and kfree(ctx) operate on a freed context. Move idxd_wq_get() before file-device setup can fail, since the release callback always calls idxd_wq_put(). Then unlock wq->wq_lock before put_device(fdev) and return directly from the file-device setup failure path, leaving ctx cleanup to the release callback. Fixes: e6fd6d7e5f0fe ("dmaengine: idxd: add a device to represent the file opened") Signed-off-by: Yuho Choi Reviewed-by: Dave Jiang Acked-by: Vinicius Costa Gomes Link: https://patch.msgid.link/20260525141550.1385581-1-dbgh9129@gmail.com Signed-off-by: Vinod Koul --- diff --git a/drivers/dma/idxd/cdev.c b/drivers/dma/idxd/cdev.c index 0366c7cf3502..82b07cf942ef 100644 --- a/drivers/dma/idxd/cdev.c +++ b/drivers/dma/idxd/cdev.c @@ -288,6 +288,7 @@ static int idxd_cdev_open(struct inode *inode, struct file *filp) fdev->parent = cdev_dev(idxd_cdev); fdev->bus = &dsa_bus_type; fdev->type = &idxd_cdev_file_type; + idxd_wq_get(wq); rc = dev_set_name(fdev, "file%d", ctx->id); if (rc < 0) { @@ -301,13 +302,14 @@ static int idxd_cdev_open(struct inode *inode, struct file *filp) goto failed_dev_add; } - idxd_wq_get(wq); mutex_unlock(&wq->wq_lock); return 0; failed_dev_add: failed_dev_name: + mutex_unlock(&wq->wq_lock); put_device(fdev); + return rc; failed_ida: failed_set_pasid: if (device_user_pasid_enabled(idxd))