ANDROID: irq: put irq_resolve_mapping under protection of __irq_enter_raw
With commit 3f9d45d8021df4739103db8f902f588782c4f81b
("ANDROID: genirq: Allow an interrupt to be marked
as 'raw'"), irq_find_mapping was moved out of scope between
irq_enter() and irq_exit(). This result in
el1_irq->__handle_domain_irq->
irq_find_mapping->rcu_read_unlock->rcu_read_unlock_special->
irq_work_queue_on->el1_irq because ir_irq() return false.
Now one RCU stall issue was observed due to IPI_IRQ_WORK irq storm.
IPI_IRQ_WORK irq was triggered from handle_domain_irq->...->
rcu_read_unlock_special->irq_work_queue_on again and again unexpectedly
due to in_irq() return false even it is in IRQ context.
This patch fix its side effect without reverting commit
3f9d45d8021df4739103db8f902f588782c4f81b.
During call path "handle_domain_irq->irq_find_mapping->...->
rcu_read_unlock_special()" with use_softirq is true.
1)before this patch, in_irq() is false
This will result in IPI_IRQ_WORK irq storm due to next IPI_IRQ_WORK
irq
will be triggered under IRQ context again and again.
2)after this patch,in_irq() will be true
RCU_SOFTIRQ will be raised(but not next IPI_IRQ_WORK irq) under IRQ
context.
Bug: 339061905
Bug: 346670587
Fixes: 3f9d45d8021d ("FROMLIST: genirq: Allow an interrupt to be marked as 'raw'")
Change-Id: I27caeaf6817e42b3c15effe8b750cb83af90aeb3
Signed-off-by: lei.zhang8 <lei.zhang8@transsion.com>
(cherry picked from commit 923b677c934b47d38c0e1044a61a3087408a3937)
diff --git a/kernel/irq/irqdesc.c b/kernel/irq/irqdesc.c
index 67d73af..74df028 100644
--- a/kernel/irq/irqdesc.c
+++ b/kernel/irq/irqdesc.c
@@ -676,8 +676,11 @@
int ret = 0;
#ifdef CONFIG_IRQ_DOMAIN
- if (lookup)
+ if (lookup) {
+ __irq_enter_raw();
irq = irq_find_mapping(domain, hwirq);
+ __irq_exit_raw();
+ }
#endif
/*
