[PATCH v3 1/2] irqchip/gicv3: Spell out when pseudo-NMIs are enabled

Alexandru Elisei alexandru.elisei at arm.com
Sat Sep 12 11:37:06 EDT 2020

When NMIs cannot be enabled, the driver prints a message stating that
unambiguously. When they are enabled, the only feedback we get is a message
regarding the use of synchronization for ICC_PMR_EL1 writes, which is not
as useful for a user who is not intimately familiar with how NMIs are

Let's make it obvious that pseudo-NMIs are enabled. Keep the message about
using a barrier for ICC_PMR_EL1 writes, because it has a non-negligible
impact on performance.

Signed-off-by: Alexandru Elisei <alexandru.elisei at arm.com>
 drivers/irqchip/irq-gic-v3.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/irqchip/irq-gic-v3.c b/drivers/irqchip/irq-gic-v3.c
index 850842f27bee..aa9b43d412b2 100644
--- a/drivers/irqchip/irq-gic-v3.c
+++ b/drivers/irqchip/irq-gic-v3.c
@@ -1564,8 +1564,8 @@ static void gic_enable_nmi_support(void)
 	if (gic_read_ctlr() & ICC_CTLR_EL1_PMHE_MASK)
-	pr_info("%s ICC_PMR_EL1 synchronisation\n",
-		static_branch_unlikely(&gic_pmr_sync) ? "Forcing" : "Relaxing");
+	pr_info("Pseudo-NMIs enabled using %s ICC_PMR_EL1 synchronisation\n",
+		static_branch_unlikely(&gic_pmr_sync) ? "forced" : "relaxed");

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