[PATCH 5.7 053/112] irqchip/gic-v4.1: Use readx_poll_timeout_atomic() to fix sleep in atomic

Greg Kroah-Hartman
2020-07-07T15:24:45Z

From: Zenghui Yu <yuzenghui@huawei.com>

[ Upstream commit 31dbb6b1d025506b3b8b8b74e9b697df47b9f696 ]

readx_poll_timeout() can sleep if @sleep_us is specified by the caller,
and is therefore unsafe to be used inside the atomic context, which is
this case when we use it to poll the GICR_VPENDBASER.Dirty bit in
irq_set_vcpu_affinity() callback.

Let's convert to its atomic version instead which helps to get the v4.1
board back to life!

Fixes: 96806229ca03 ("irqchip/gic-v4.1: Add support for VPENDBASER's Dirty+Valid signaling")
Signed-off-by: Zenghui Yu <yuzenghui@huawei.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200605052345.1494-1-yuzenghui@huawei.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/irqchip/irq-gic-v3-its.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
index 124251b0ccbae..b3e16a06c13b7 100644
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -3681,10 +3681,10 @@ static void its_wait_vpt_parse_complete(void)
if (!gic_rdists->has_vpend_valid_dirty)
return;

- WARN_ON_ONCE(readq_relaxed_poll_timeout(vlpi_base + GICR_VPENDBASER,
- val,
- !(val & GICR_VPENDBASER_Dirty),
- 10, 500));
+ WARN_ON_ONCE(readq_relaxed_poll_timeout_atomic(vlpi_base + GICR_VPENDBASER,
+ val,
+ !(val & GICR_VPENDBASER_Dirty),
+ 10, 500));
}

static void its_vpe_schedule(struct its_vpe *vpe)
--
2.25.1