From 951ec00658134e2e38ff8a11bb5876ed72e68f01 Mon Sep 17 00:00:00 2001 From: Keith Busch Date: Wed, 27 Apr 2016 14:22:32 -0600 Subject: [PATCH] x86/apic: Handle zero vector gracefully in clear_vector_irq() If x86_vector_alloc_irq() fails x86_vector_free_irqs() is invoked to cleanup the already allocated vectors. This subsequently calls clear_vector_irq(). The failed irq has no vector assigned, which triggers the BUG_ON(!vector) in clear_vector_irq(). We cannot suppress the call to x86_vector_free_irqs() for the failed interrupt, because the other data related to this irq must be cleaned up as well. So calling clear_vector_irq() with vector == 0 is legitimate. Remove the BUG_ON and return if vector is zero, [ tglx: Massaged changelog ] Fixes: b5dc8e6c21e7 "x86/irq: Use hierarchical irqdomain to manage CPU interrupt vectors" Signed-off-by: Keith Busch Cc: stable@vger.kernel.org Signed-off-by: Thomas Gleixner (cherry picked from commit 1bdb8970392a68489b469c3a330a1adb5ef61beb) Orabug: 24515998,25975565 Signed-off-by: Ethan Zhao Reviewed-by: Yuval Shaia Reviewed-by: Jack Vogel Conflicts: arch/x86/kernel/apic/vector.c --- arch/x86/kernel/apic/vector.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/arch/x86/kernel/apic/vector.c b/arch/x86/kernel/apic/vector.c index 78497c2e9015..171f89adef59 100644 --- a/arch/x86/kernel/apic/vector.c +++ b/arch/x86/kernel/apic/vector.c @@ -208,7 +208,10 @@ void clear_irq_vector(int irq, struct irq_cfg *cfg) unsigned long flags; raw_spin_lock_irqsave(&vector_lock, flags); - BUG_ON(!cfg->vector); + if (!cfg->vector) { + raw_spin_unlock_irqrestore(&vector_lock, flags); + return; + } vector = cfg->vector; for_each_cpu_and(cpu, cfg->domain, cpu_online_mask) -- 2.50.1