From 46135d6f878ab00261d4a2082d620bfb41019aab Mon Sep 17 00:00:00 2001 From: Lorenzo Pieralisi Date: Wed, 17 Mar 2021 10:07:19 +0000 Subject: irqchip/gic-v4.1: Disable vSGI upon (GIC CPUIF < v4.1) detection GIC CPU interfaces versions predating GIC v4.1 were not built to accommodate vINTID within the vSGI range; as reported in the GIC specifications (8.2 "Changes to the CPU interface"), it is CONSTRAINED UNPREDICTABLE to deliver a vSGI to a PE with ID_AA64PFR0_EL1.GIC < b0011. Check the GIC CPUIF version by reading the SYS_ID_AA64_PFR0_EL1. Disable vSGIs if a CPUIF version < 4.1 is detected to prevent using vSGIs on systems where they may misbehave. Signed-off-by: Lorenzo Pieralisi Cc: Marc Zyngier Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20210317100719.3331-2-lorenzo.pieralisi@arm.com --- drivers/irqchip/irq-gic-v4.c | 27 +++++++++++++++++++++++++-- 1 file changed, 25 insertions(+), 2 deletions(-) (limited to 'drivers/irqchip') diff --git a/drivers/irqchip/irq-gic-v4.c b/drivers/irqchip/irq-gic-v4.c index 5d1dc9915272..4ea71b28f9f5 100644 --- a/drivers/irqchip/irq-gic-v4.c +++ b/drivers/irqchip/irq-gic-v4.c @@ -87,17 +87,40 @@ static struct irq_domain *gic_domain; static const struct irq_domain_ops *vpe_domain_ops; static const struct irq_domain_ops *sgi_domain_ops; +#ifdef CONFIG_ARM64 +#include + +bool gic_cpuif_has_vsgi(void) +{ + unsigned long fld, reg = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1); + + fld = cpuid_feature_extract_unsigned_field(reg, ID_AA64PFR0_GIC_SHIFT); + + return fld >= 0x3; +} +#else +bool gic_cpuif_has_vsgi(void) +{ + return false; +} +#endif + static bool has_v4_1(void) { return !!sgi_domain_ops; } +static bool has_v4_1_sgi(void) +{ + return has_v4_1() && gic_cpuif_has_vsgi(); +} + static int its_alloc_vcpu_sgis(struct its_vpe *vpe, int idx) { char *name; int sgi_base; - if (!has_v4_1()) + if (!has_v4_1_sgi()) return 0; name = kasprintf(GFP_KERNEL, "GICv4-sgi-%d", task_pid_nr(current)); @@ -182,7 +205,7 @@ static void its_free_sgi_irqs(struct its_vm *vm) { int i; - if (!has_v4_1()) + if (!has_v4_1_sgi()) return; for (i = 0; i < vm->nr_vpes; i++) { -- cgit