hid-core: fix lockdep in hid_input_report() v2

[Krzysztof Helt]

From: Krzysztof Helt <krzysztof.h1@xxxxx>

There is a lockdep warning in the hid_input_report() due to kmalloc(.,GFP_KERNEL) 
allocation of a temporary buffer.
Change hid_input_report() call inside the hid_ctrl() after Jiri Slaby's advice. This 
converts kmalloc() call into kmalloc(.,GFP_ATOMIC).

The lockdep trace is:

WARNING: at kernel/lockdep.c:2457 lockdep_trace_alloc+0xca/0xd0()
Hardware name: Product Name
Modules linked in: usbhid(+) hid uhci_hcd ne2k_pci via_agp 8390 i2c_via
Pid: 0, comm: swapper Not tainted 2.6.31 #74
Call Trace:
 [<c0243b8a>] ? lockdep_trace_alloc+0xca/0xd0
 [<c0221d1c>] warn_slowpath_common+0x7c/0xa0
 [<c0243b8a>] ? lockdep_trace_alloc+0xca/0xd0
 [<c0221d55>] warn_slowpath_null+0x15/0x20
 [<c0243b8a>] lockdep_trace_alloc+0xca/0xd0
 [<c027d2c8>] kmem_cache_alloc+0x28/0x100
 [<cc9359ef>] ? hid_input_report+0x6f/0x220 [hid]
 [<cc9359ef>] hid_input_report+0x6f/0x220 [hid]
 [<cc94cabf>] hid_ctrl+0x7f/0x180 [usbhid]
 [<c03b28b1>] usb_hcd_giveback_urb+0x41/0xa0
 [<cc91a3fc>] uhci_giveback_urb+0x8c/0x280 [uhci_hcd]
 [<c0279853>] ? dma_pool_free+0xd3/0x120
 [<cc919848>] ? uhci_free_td+0x58/0xa0 [uhci_hcd]
 [<cc91ac01>] uhci_scan_schedule+0x301/0x910 [uhci_hcd]
 [<cc91cac4>] uhci_irq+0x94/0x940 [uhci_hcd]
 [<c0245c43>] ? __lock_acquire+0x433/0xab0
 [<c0206246>] ? mask_and_ack_8259A+0x66/0x100
 [<c03b494b>] usb_hcd_irq+0x6b/0x90
 [<c0255e7d>] handle_IRQ_event+0x2d/0xc0
 [<c0257e85>] handle_level_irq+0x65/0xe0
 [<c0204c74>] handle_irq+0x34/0x60
 [<c0204bc9>] do_IRQ+0x39/0xb0
 [<c024365c>] ? trace_hardirqs_on_caller+0x12c/0x180
 [<c020328e>] common_interrupt+0x2e/0x40
 [<c0208d48>] ? default_idle+0x38/0x50
 [<c02108df>] apm_cpu_idle+0x10f/0x290
 [<c0201b11>] cpu_idle+0x21/0x40
 [<c045892d>] rest_init+0x4d/0x60
 [<c0575815>] start_kernel+0x235/0x280
 [<c05751f0>] ? unknown_bootoption+0x0/0x210
 [<c057503f>] __init_begin+0x3f/0x50

Signed-off-by: Krzysztof Helt <krzysztof.h1@xxxxx>
---
This lockdep is in the current git tree.

diff --git a/drivers/hid/usbhid/hid-core.c b/drivers/hid/usbhid/hid-core.c
index 1b0e07a..ab2869d 100644
--- a/drivers/hid/usbhid/hid-core.c
+++ b/drivers/hid/usbhid/hid-core.c
@@ -455,7 +455,7 @@ static void hid_ctrl(struct urb *urb)
 		if (usbhid->ctrl[usbhid->ctrltail].dir == USB_DIR_IN)
 			hid_input_report(urb->context,
 				usbhid->ctrl[usbhid->ctrltail].report->type,
-				urb->transfer_buffer, urb->actual_length, 0);
+				urb->transfer_buffer, urb->actual_length, 1);
 		break;
 	case -ESHUTDOWN:	/* unplug */
 		unplug = 1;
--
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