virtio_pmem: Check device status before requesting flush

[ Upstream commit e25fbcd97cf52c3c9824d44b5c56c19673c3dd50 ]

If a pmem device is in a bad status, the driver side could wait for
host ack forever in virtio_pmem_flush(), causing the system to hang.

So add a status check in the beginning of virtio_pmem_flush() to return
early if the device is not activated.

Signed-off-by: Philip Chen <philipchen@chromium.org>
Message-Id: <20240826215313.2673566-1-philipchen@chromium.org>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/nvdimm/nd_virtio.c b/drivers/nvdimm/nd_virtio.c
index 10351d5b49fac0720b6f7e708c1e3f4ffeebe310..41e97c6567cf90b52e57ea14d98f2e2c0e0624e2 100644 (file)
--- a/drivers/nvdimm/nd_virtio.c
+++ b/drivers/nvdimm/nd_virtio.c
@@ -44,6 +44,15 @@ static int virtio_pmem_flush(struct nd_region *nd_region)
        unsigned long flags;
        int err, err1;
 
+       /*
+        * Don't bother to submit the request to the device if the device is
+        * not activated.
+        */
+       if (vdev->config->get_status(vdev) & VIRTIO_CONFIG_S_NEEDS_RESET) {
+               dev_info(&vdev->dev, "virtio pmem device needs a reset\n");
+               return -EIO;
+       }
+
        might_sleep();
        req_data = kmalloc(sizeof(*req_data), GFP_KERNEL);
        if (!req_data)