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

From: Greg KH
Date: Wed Jun 01 2011 - 04:47:35 EST

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

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,
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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