[076/165] x86, ioapic: Fix potential resume deadlock

[Greg KH]

2.6.39-stable review patch.  If anyone has any objections, please let us know.

------------------
Content-Length: 1478
Lines: 44

From: Daniel J Blueman <daniel.blueman@xxxxxxxxx>

commit b64ce24daffb634b5b3133a2e411bd4de50654e8 upstream.

Fix a potential deadlock when resuming; here the calling
function has disabled interrupts, so we cannot sleep.

Change the memory allocation flag from GFP_KERNEL to GFP_ATOMIC.

TODO: We can do away with this memory allocation during resume
      by reusing the ioapic suspend/resume code that uses boot time
      allocated buffers, but we want to keep this -stable patch
      simple.

Signed-off-by: Daniel J Blueman <daniel.blueman@xxxxxxxxx>
Signed-off-by: Suresh Siddha <suresh.b.siddha@xxxxxxxxx>
Link: http://lkml.kernel.org/r/20110518233157.385970138@xxxxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>

---
 arch/x86/kernel/apic/io_apic.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/arch/x86/kernel/apic/io_apic.c
+++ b/arch/x86/kernel/apic/io_apic.c
@@ -621,14 +621,14 @@ struct IO_APIC_route_entry **alloc_ioapi
 	struct IO_APIC_route_entry **ioapic_entries;
 
 	ioapic_entries = kzalloc(sizeof(*ioapic_entries) * nr_ioapics,
-				GFP_KERNEL);
+				GFP_ATOMIC);
 	if (!ioapic_entries)
 		return 0;
 
 	for (apic = 0; apic < nr_ioapics; apic++) {
 		ioapic_entries[apic] =
 			kzalloc(sizeof(struct IO_APIC_route_entry) *
-				nr_ioapic_registers[apic], GFP_KERNEL);
+				nr_ioapic_registers[apic], GFP_ATOMIC);
 		if (!ioapic_entries[apic])
 			goto nomem;
 	}


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