From: Marc Zyngier maz@kernel.org
[ Upstream commit 926846a703cbf5d0635cc06e67d34b228746554b ]
We normally rely on the irq_to_cpuid_[un]lock() primitives to make sure nothing will change col->idx while performing a LPI invalidation.
However, these primitives do not cover VPE doorbells, and we have some open-coded locking for that. Unfortunately, this locking is pretty bogus.
Instead, extend the above primitives to cover VPE doorbells and convert the whole thing to it.
Fixes: f3a059219bc7 ("irqchip/gic-v4.1: Ensure mutual exclusion between vPE affinity change and RD access") Reported-by: Kunkun Jiang jiangkunkun@huawei.com Signed-off-by: Marc Zyngier maz@kernel.org Cc: Zenghui Yu yuzenghui@huawei.com Cc: wanghaibin.wang@huawei.com Tested-by: Kunkun Jiang jiangkunkun@huawei.com Reviewed-by: Zenghui Yu yuzenghui@huawei.com Link: https://lore.kernel.org/r/20230617073242.3199746-1-maz@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/irqchip/irq-gic-v3-its.c | 75 ++++++++++++++++++++------------ 1 file changed, 46 insertions(+), 29 deletions(-)
diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c index 59a5d06b2d3e4..490e6cfe510e6 100644 --- a/drivers/irqchip/irq-gic-v3-its.c +++ b/drivers/irqchip/irq-gic-v3-its.c @@ -267,13 +267,23 @@ static void vpe_to_cpuid_unlock(struct its_vpe *vpe, unsigned long flags) raw_spin_unlock_irqrestore(&vpe->vpe_lock, flags); }
+static struct irq_chip its_vpe_irq_chip; + static int irq_to_cpuid_lock(struct irq_data *d, unsigned long *flags) { - struct its_vlpi_map *map = get_vlpi_map(d); + struct its_vpe *vpe = NULL; int cpu;
- if (map) { - cpu = vpe_to_cpuid_lock(map->vpe, flags); + if (d->chip == &its_vpe_irq_chip) { + vpe = irq_data_get_irq_chip_data(d); + } else { + struct its_vlpi_map *map = get_vlpi_map(d); + if (map) + vpe = map->vpe; + } + + if (vpe) { + cpu = vpe_to_cpuid_lock(vpe, flags); } else { /* Physical LPIs are already locked via the irq_desc lock */ struct its_device *its_dev = irq_data_get_irq_chip_data(d); @@ -287,10 +297,18 @@ static int irq_to_cpuid_lock(struct irq_data *d, unsigned long *flags)
static void irq_to_cpuid_unlock(struct irq_data *d, unsigned long flags) { - struct its_vlpi_map *map = get_vlpi_map(d); + struct its_vpe *vpe = NULL; + + if (d->chip == &its_vpe_irq_chip) { + vpe = irq_data_get_irq_chip_data(d); + } else { + struct its_vlpi_map *map = get_vlpi_map(d); + if (map) + vpe = map->vpe; + }
- if (map) - vpe_to_cpuid_unlock(map->vpe, flags); + if (vpe) + vpe_to_cpuid_unlock(vpe, flags); }
static struct its_collection *valid_col(struct its_collection *col) @@ -1427,14 +1445,29 @@ static void wait_for_syncr(void __iomem *rdbase) cpu_relax(); }
-static void direct_lpi_inv(struct irq_data *d) +static void __direct_lpi_inv(struct irq_data *d, u64 val) { - struct its_vlpi_map *map = get_vlpi_map(d); void __iomem *rdbase; unsigned long flags; - u64 val; int cpu;
+ /* Target the redistributor this LPI is currently routed to */ + cpu = irq_to_cpuid_lock(d, &flags); + raw_spin_lock(&gic_data_rdist_cpu(cpu)->rd_lock); + + rdbase = per_cpu_ptr(gic_rdists->rdist, cpu)->rd_base; + gic_write_lpir(val, rdbase + GICR_INVLPIR); + wait_for_syncr(rdbase); + + raw_spin_unlock(&gic_data_rdist_cpu(cpu)->rd_lock); + irq_to_cpuid_unlock(d, flags); +} + +static void direct_lpi_inv(struct irq_data *d) +{ + struct its_vlpi_map *map = get_vlpi_map(d); + u64 val; + if (map) { struct its_device *its_dev = irq_data_get_irq_chip_data(d);
@@ -1447,15 +1480,7 @@ static void direct_lpi_inv(struct irq_data *d) val = d->hwirq; }
- /* Target the redistributor this LPI is currently routed to */ - cpu = irq_to_cpuid_lock(d, &flags); - raw_spin_lock(&gic_data_rdist_cpu(cpu)->rd_lock); - rdbase = per_cpu_ptr(gic_rdists->rdist, cpu)->rd_base; - gic_write_lpir(val, rdbase + GICR_INVLPIR); - - wait_for_syncr(rdbase); - raw_spin_unlock(&gic_data_rdist_cpu(cpu)->rd_lock); - irq_to_cpuid_unlock(d, flags); + __direct_lpi_inv(d, val); }
static void lpi_update_config(struct irq_data *d, u8 clr, u8 set) @@ -3936,18 +3961,10 @@ static void its_vpe_send_inv(struct irq_data *d) { struct its_vpe *vpe = irq_data_get_irq_chip_data(d);
- if (gic_rdists->has_direct_lpi) { - void __iomem *rdbase; - - /* Target the redistributor this VPE is currently known on */ - raw_spin_lock(&gic_data_rdist_cpu(vpe->col_idx)->rd_lock); - rdbase = per_cpu_ptr(gic_rdists->rdist, vpe->col_idx)->rd_base; - gic_write_lpir(d->parent_data->hwirq, rdbase + GICR_INVLPIR); - wait_for_syncr(rdbase); - raw_spin_unlock(&gic_data_rdist_cpu(vpe->col_idx)->rd_lock); - } else { + if (gic_rdists->has_direct_lpi) + __direct_lpi_inv(d, d->parent_data->hwirq); + else its_vpe_send_cmd(vpe, its_send_inv); - } }
static void its_vpe_mask_irq(struct irq_data *d)