The following commit has been merged into the irq/core branch of tip:
Commit-ID: 2234ae846ccb9ebdf4c391824cb79e73674dceda
Gitweb: https://git.kernel.org/tip/2234ae846ccb9ebdf4c391824cb79e73674dceda
Author: Anup Patel <anup.patel@xxxxxxx>
AuthorDate: Mon, 18 May 2020 14:44:40 +05:30
Committer: Marc Zyngier <maz@xxxxxxxxxx>
CommitterDate: Mon, 25 May 2020 10:36:53 +01:00
irqchip/sifive-plic: Setup cpuhp once after boot CPU handler is present
For multiple PLIC instances, the plic_init() is called once for each
PLIC instance. Due to this we have two issues:
1. cpuhp_setup_state() is called multiple times
2. plic_starting_cpu() can crash for boot CPU if cpuhp_setup_state()
is called before boot CPU PLIC handler is available.
Address both issues by only initializing the HP notifiers when
the boot CPU setup is complete.
Fixes: f1ad1133b18f ("irqchip/sifive-plic: Add support for multiple PLICs")
Signed-off-by: Anup Patel <anup.patel@xxxxxxx>
Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@xxxxxxxxxx>
Acked-by: Palmer Dabbelt <palmerdabbelt@xxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Link: https://lore.kernel.org/r/20200518091441.94843-3-anup.patel@xxxxxxx
---
drivers/irqchip/irq-sifive-plic.c | 14 ++++++++++++--
1 file changed, 12 insertions(+), 2 deletions(-)
diff --git a/drivers/irqchip/irq-sifive-plic.c b/drivers/irqchip/irq-sifive-plic.c
index 9f7f8ce..6c54abf 100644
--- a/drivers/irqchip/irq-sifive-plic.c
+++ b/drivers/irqchip/irq-sifive-plic.c
@@ -76,6 +76,7 @@ struct plic_handler {
void __iomem *enable_base;
struct plic_priv *priv;
};
+static bool plic_cpuhp_setup_done;
static DEFINE_PER_CPU(struct plic_handler, plic_handlers);
static inline void plic_toggle(struct plic_handler *handler,
@@ -285,6 +286,7 @@ static int __init plic_init(struct device_node *node,
int error = 0, nr_contexts, nr_handlers = 0, i;
u32 nr_irqs;
struct plic_priv *priv;
+ struct plic_handler *handler;
priv = kzalloc(sizeof(*priv), GFP_KERNEL);
if (!priv)
@@ -313,7 +315,6 @@ static int __init plic_init(struct device_node *node,
for (i = 0; i < nr_contexts; i++) {
struct of_phandle_args parent;
- struct plic_handler *handler;
irq_hw_number_t hwirq;
int cpu, hartid;
@@ -367,9 +368,18 @@ done:
nr_handlers++;
}
- cpuhp_setup_state(CPUHP_AP_IRQ_SIFIVE_PLIC_STARTING,
+ /*
+ * We can have multiple PLIC instances so setup cpuhp state only
+ * when context handler for current/boot CPU is present.
+ */
+ handler = this_cpu_ptr(&plic_handlers);
+ if (handler->present && !plic_cpuhp_setup_done) {
+ cpuhp_setup_state(CPUHP_AP_IRQ_SIFIVE_PLIC_STARTING,
"irqchip/sifive/plic:starting",
plic_starting_cpu, plic_dying_cpu);
+ plic_cpuhp_setup_done = true;
+ }
+
pr_info("mapped %d interrupts with %d handlers for %d contexts.\n",
nr_irqs, nr_handlers, nr_contexts);
set_handle_irq(plic_handle_irq);
|