diff options
Diffstat (limited to 'drivers/irqchip/irq-gic-v3.c')
| -rw-r--r-- | drivers/irqchip/irq-gic-v3.c | 42 |
1 files changed, 38 insertions, 4 deletions
diff --git a/drivers/irqchip/irq-gic-v3.c b/drivers/irqchip/irq-gic-v3.c index 37a23aa6de37..e0f4debe64e1 100644 --- a/drivers/irqchip/irq-gic-v3.c +++ b/drivers/irqchip/irq-gic-v3.c @@ -103,7 +103,7 @@ EXPORT_SYMBOL(gic_nonsecure_priorities); /* ppi_nmi_refs[n] == number of cpus having ppi[n + 16] set as NMI */ static refcount_t *ppi_nmi_refs; -static struct gic_kvm_info gic_v3_kvm_info; +static struct gic_kvm_info gic_v3_kvm_info __initdata; static DEFINE_PER_CPU(bool, has_rss); #define MPIDR_RS(mpidr) (((mpidr) & 0xF0UL) >> 4) @@ -642,11 +642,45 @@ static inline void gic_handle_nmi(u32 irqnr, struct pt_regs *regs) nmi_exit(); } +static u32 do_read_iar(struct pt_regs *regs) +{ + u32 iar; + + if (gic_supports_nmi() && unlikely(!interrupts_enabled(regs))) { + u64 pmr; + + /* + * We were in a context with IRQs disabled. However, the + * entry code has set PMR to a value that allows any + * interrupt to be acknowledged, and not just NMIs. This can + * lead to surprising effects if the NMI has been retired in + * the meantime, and that there is an IRQ pending. The IRQ + * would then be taken in NMI context, something that nobody + * wants to debug twice. + * + * Until we sort this, drop PMR again to a level that will + * actually only allow NMIs before reading IAR, and then + * restore it to what it was. + */ + pmr = gic_read_pmr(); + gic_pmr_mask_irqs(); + isb(); + + iar = gic_read_iar(); + + gic_write_pmr(pmr); + } else { + iar = gic_read_iar(); + } + + return iar; +} + static asmlinkage void __exception_irq_entry gic_handle_irq(struct pt_regs *regs) { u32 irqnr; - irqnr = gic_read_iar(); + irqnr = do_read_iar(regs); /* Check for special IDs first */ if ((irqnr >= 1020 && irqnr <= 1023)) @@ -1852,7 +1886,7 @@ static void __init gic_of_setup_kvm_info(struct device_node *node) gic_v3_kvm_info.has_v4 = gic_data.rdists.has_vlpis; gic_v3_kvm_info.has_v4_1 = gic_data.rdists.has_rvpeid; - gic_set_kvm_info(&gic_v3_kvm_info); + vgic_set_kvm_info(&gic_v3_kvm_info); } static int __init gic_of_init(struct device_node *node, struct device_node *parent) @@ -2168,7 +2202,7 @@ static void __init gic_acpi_setup_kvm_info(void) gic_v3_kvm_info.has_v4 = gic_data.rdists.has_vlpis; gic_v3_kvm_info.has_v4_1 = gic_data.rdists.has_rvpeid; - gic_set_kvm_info(&gic_v3_kvm_info); + vgic_set_kvm_info(&gic_v3_kvm_info); } static int __init |