[PATCH v2 1/6] irqchip: gicv3-its: zero itt before handling to hardware

From: Yun Wu
Date: Sun Feb 15 2015 - 04:33:40 EST


Some kind of brain-dead implementations chooses to insert ITEes in
rapid sequence of disabled ITEes, and an un-zeroed ITT will confuse
ITS on judging whether an ITE is really enabled or not. Considering
the implementations are still supported by the GICv3 architecture,
in which ITT is not required to be zeroed before being handled to
hardware, we do the favor in ITS driver.

Acked-by: Marc Zyngier <marc.zyngier@xxxxxxx>
Signed-off-by: Yun Wu <wuyun.wu@xxxxxxxxxx>
---
drivers/irqchip/irq-gic-v3-its.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
index 6850141..69eeea3 100644
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -1076,7 +1076,7 @@ static struct its_device *its_create_device(struct its_node *its, u32 dev_id,
nr_ites = max(2UL, roundup_pow_of_two(nvecs));
sz = nr_ites * its->ite_size;
sz = max(sz, ITS_ITT_ALIGN) + ITS_ITT_ALIGN - 1;
- itt = kmalloc(sz, GFP_KERNEL);
+ itt = kzalloc(sz, GFP_KERNEL);
lpi_map = its_lpi_alloc_chunks(nvecs, &lpi_base, &nr_lpis);

if (!dev || !itt || !lpi_map) {
--
1.8.0


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