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ANDROID: irq: put irq_resolve_mapping under protection of __irq_enter_raw

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With commit a879ad2ff0 ("ANDROID: genirq: Allow an interrupt to be marked
as 'raw'"), irq_resolve_mapping was moved out of scope between
irq_enter() and irq_exit(). This result in  handle_domain_irq->
irq_resolve_mapping->__irq_resolve_mapping->rcu_read_unlock->
__rcu_read_unlock->rcu_read_unlock_special->in_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 a879ad2ff0.
During call path "handle_domain_irq->irq_resolve_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: 261364180
Fixes: a879ad2ff0 ("ANDROID: genirq: Allow an interrupt to be marked as 'raw'")
Change-Id: I447e5718694ebfaa11bfe4ef620d85646d5b49d6
Signed-off-by: Major chen <major.chen@samsung.com>
Signed-off-by: Euiyoul Ryu <ryu.real@samsung.com>
This commit is contained in:
Major chen
2022-12-06 15:37:09 +08:00
committed by Will Deacon
parent aea6e535a2
commit 474a540f29
1 changed files with 2 additions and 0 deletions
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2
kernel/irq/irqdesc.c
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@@ -694,8 +694,10 @@ int handle_domain_irq(struct irq_domain *domain,
int ret = 0;
__irq_enter_raw();
/* The irqdomain code provides boundary checks */
desc = irq_resolve_mapping(domain, hwirq);
__irq_exit_raw();
if (likely(desc)) {
if (IS_ENABLED(CONFIG_ARCH_WANTS_IRQ_RAW) &&
unlikely(irq_settings_is_raw(desc))) {