[PATCH 4.15 38/45] xhci: Fix xhci debugfs devices node disappearance after hibernation

From: Greg Kroah-Hartman
Date: Fri Feb 23 2018 - 13:58:49 EST


4.15-stable review patch. If anyone has any objections, please let me know.

------------------

From: Zhengjun Xing <zhengjun.xing@xxxxxxxxxxxxxxx>

commit d91676717261578f429d3577dbe9154b26e8abf7 upstream.

During system resume from hibernation, xhci host is reset, all the
nodes in devices folder are removed in xhci_mem_cleanup function.
Later nodes in /sys/kernel/debug/usb/xhci/* are created again in
function xhci_run, but the nodes already exist, so the nodes still
keep the old ones, finally device nodes in xhci debugfs folder
/sys/kernel/debug/usb/xhci/*/devices/* are disappeared.

This fix removed xhci debugfs nodes before the nodes are re-created,
so all the nodes in xhci debugfs can be re-created successfully.

Fixes: 02b6fdc2a153 ("usb: xhci: Add debugfs interface for xHCI driver")
Cc: <stable@xxxxxxxxxxxxxxx> # v4.15
Signed-off-by: Zhengjun Xing <zhengjun.xing@xxxxxxxxxxxxxxx>
Signed-off-by: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/usb/host/xhci.c | 1 +
1 file changed, 1 insertion(+)

--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -1018,6 +1018,7 @@ int xhci_resume(struct xhci_hcd *xhci, b

xhci_dbg(xhci, "cleaning up memory\n");
xhci_mem_cleanup(xhci);
+ xhci_debugfs_exit(xhci);
xhci_dbg(xhci, "xhci_stop completed - status = %x\n",
readl(&xhci->op_regs->status));