diff options
authorSergio Aguirre <>2013-04-04 10:32:13 -0700
committerGreg Kroah-Hartman <>2013-06-13 09:44:50 -0700
commitc5d2935c1ce3d8c8bde02b744c55c10953d411dd (patch)
parent6eb953e922b384e3b42418fdbc44db4da3dfea65 (diff)
xhci-mem: init list heads at the beginning of init
commit 331de00a64e5027365145bdf51da27b9ce15dfd5 upstream. It is possible that we fail on xhci_mem_init, just before doing the INIT_LIST_HEAD, and calling xhci_mem_cleanup. Problem is that, the list_for_each_entry_safe macro, assumes list heads are initialized (not NULL), and dereferences their 'next' pointer, causing a kernel panic if this is not yet initialized. Let's protect from that by moving inits to the beginning. This patch should be backported to kernels as old as 3.2, that contain the commit 9574323c39d1f8359a04843075d89c9f32d8b7e6 "xHCI: test USB2 software LPM". Signed-off-by: Sergio Aguirre <> Acked-by: David Cohen <> Signed-off-by: Sarah Sharp <> Signed-off-by: Greg Kroah-Hartman <>
1 files changed, 3 insertions, 3 deletions
diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c
index f0592220e601..e53efa7560f4 100644
--- a/drivers/usb/host/xhci-mem.c
+++ b/drivers/usb/host/xhci-mem.c
@@ -2274,6 +2274,9 @@ int xhci_mem_init(struct xhci_hcd *xhci, gfp_t flags)
u32 page_size, temp;
int i;
+ INIT_LIST_HEAD(&xhci->lpm_failed_devs);
+ INIT_LIST_HEAD(&xhci->cancel_cmd_list);
page_size = xhci_readl(xhci, &xhci->op_regs->page_size);
xhci_dbg(xhci, "Supported page size register = 0x%x\n", page_size);
for (i = 0; i < 16; i++) {
@@ -2352,7 +2355,6 @@ int xhci_mem_init(struct xhci_hcd *xhci, gfp_t flags)
xhci->cmd_ring = xhci_ring_alloc(xhci, 1, 1, TYPE_COMMAND, flags);
if (!xhci->cmd_ring)
goto fail;
- INIT_LIST_HEAD(&xhci->cancel_cmd_list);
xhci_dbg(xhci, "Allocated command ring at %p\n", xhci->cmd_ring);
xhci_dbg(xhci, "First segment DMA is 0x%llx\n",
(unsigned long long)xhci->cmd_ring->first_seg->dma);
@@ -2453,8 +2455,6 @@ int xhci_mem_init(struct xhci_hcd *xhci, gfp_t flags)
if (xhci_setup_port_arrays(xhci, flags))
goto fail;
- INIT_LIST_HEAD(&xhci->lpm_failed_devs);
/* Enable USB 3.0 device notifications for function remote wake, which
* is necessary for allowing USB 3.0 devices to do remote wakeup from
* U3 (device suspend).