From 910e204841954b95c051b2ee49ab0f5c735ff93c Mon Sep 17 00:00:00 2001 From: Shannon Zhao Date: Fri, 8 Jun 2018 13:15:32 +0100 Subject: [PATCH] arm_gicv3_kvm: kvm_dist_get/put: skip the registers banked by GICR While we skip the GIC_INTERNAL irqs, we don't change the register offset accordingly. This will overlap the GICR registers value and leave the last GIC_INTERNAL irq's registers out of update. Fix this by skipping the registers banked by GICR. Also for migration compatibility if the migration source (old version qemu) doesn't send gicd_no_migration_shift_bug = 1 to destination, then we shift the data of PPI to get the right data for SPI. Fixes: 367b9f527becdd20ddf116e17a3c0c2bbc486920 Cc: qemu-stable@nongnu.org Reviewed-by: Eric Auger Reviewed-by: Peter Maydell Signed-off-by: Shannon Zhao Message-id: 1527816987-16108-1-git-send-email-zhaoshenglong@huawei.com Signed-off-by: Peter Maydell --- hw/intc/arm_gicv3_common.c | 79 ++++++++++++++++++++++++++++++ hw/intc/arm_gicv3_kvm.c | 38 ++++++++++++++ include/hw/intc/arm_gicv3_common.h | 1 + 3 files changed, 118 insertions(+) diff --git a/hw/intc/arm_gicv3_common.c b/hw/intc/arm_gicv3_common.c index 7b54d523762b..864b7c6515ff 100644 --- a/hw/intc/arm_gicv3_common.c +++ b/hw/intc/arm_gicv3_common.c @@ -27,6 +27,7 @@ #include "hw/intc/arm_gicv3_common.h" #include "gicv3_internal.h" #include "hw/arm/linux-boot-if.h" +#include "sysemu/kvm.h" static int gicv3_pre_save(void *opaque) { @@ -141,6 +142,79 @@ static const VMStateDescription vmstate_gicv3_cpu = { } }; +static int gicv3_gicd_no_migration_shift_bug_pre_load(void *opaque) +{ + GICv3State *cs = opaque; + + /* + * The gicd_no_migration_shift_bug flag is used for migration compatibility + * for old version QEMU which may have the GICD bmp shift bug under KVM mode. + * Strictly, what we want to know is whether the migration source is using + * KVM. Since we don't have any way to determine that, we look at whether the + * destination is using KVM; this is close enough because for the older QEMU + * versions with this bug KVM -> TCG migration didn't work anyway. If the + * source is a newer QEMU without this bug it will transmit the migration + * subsection which sets the flag to true; otherwise it will remain set to + * the value we select here. + */ + if (kvm_enabled()) { + cs->gicd_no_migration_shift_bug = false; + } + + return 0; +} + +static int gicv3_gicd_no_migration_shift_bug_post_load(void *opaque, + int version_id) +{ + GICv3State *cs = opaque; + + if (cs->gicd_no_migration_shift_bug) { + return 0; + } + + /* Older versions of QEMU had a bug in the handling of state save/restore + * to the KVM GICv3: they got the offset in the bitmap arrays wrong, + * so that instead of the data for external interrupts 32 and up + * starting at bit position 32 in the bitmap, it started at bit + * position 64. If we're receiving data from a QEMU with that bug, + * we must move the data down into the right place. + */ + memmove(cs->group, (uint8_t *)cs->group + GIC_INTERNAL / 8, + sizeof(cs->group) - GIC_INTERNAL / 8); + memmove(cs->grpmod, (uint8_t *)cs->grpmod + GIC_INTERNAL / 8, + sizeof(cs->grpmod) - GIC_INTERNAL / 8); + memmove(cs->enabled, (uint8_t *)cs->enabled + GIC_INTERNAL / 8, + sizeof(cs->enabled) - GIC_INTERNAL / 8); + memmove(cs->pending, (uint8_t *)cs->pending + GIC_INTERNAL / 8, + sizeof(cs->pending) - GIC_INTERNAL / 8); + memmove(cs->active, (uint8_t *)cs->active + GIC_INTERNAL / 8, + sizeof(cs->active) - GIC_INTERNAL / 8); + memmove(cs->edge_trigger, (uint8_t *)cs->edge_trigger + GIC_INTERNAL / 8, + sizeof(cs->edge_trigger) - GIC_INTERNAL / 8); + + /* + * While this new version QEMU doesn't have this kind of bug as we fix it, + * so it needs to set the flag to true to indicate that and it's necessary + * for next migration to work from this new version QEMU. + */ + cs->gicd_no_migration_shift_bug = true; + + return 0; +} + +const VMStateDescription vmstate_gicv3_gicd_no_migration_shift_bug = { + .name = "arm_gicv3/gicd_no_migration_shift_bug", + .version_id = 1, + .minimum_version_id = 1, + .pre_load = gicv3_gicd_no_migration_shift_bug_pre_load, + .post_load = gicv3_gicd_no_migration_shift_bug_post_load, + .fields = (VMStateField[]) { + VMSTATE_BOOL(gicd_no_migration_shift_bug, GICv3State), + VMSTATE_END_OF_LIST() + } +}; + static const VMStateDescription vmstate_gicv3 = { .name = "arm_gicv3", .version_id = 1, @@ -165,6 +239,10 @@ static const VMStateDescription vmstate_gicv3 = { VMSTATE_STRUCT_VARRAY_POINTER_UINT32(cpu, GICv3State, num_cpu, vmstate_gicv3_cpu, GICv3CPUState), VMSTATE_END_OF_LIST() + }, + .subsections = (const VMStateDescription * []) { + &vmstate_gicv3_gicd_no_migration_shift_bug, + NULL } }; @@ -364,6 +442,7 @@ static void arm_gicv3_common_reset(DeviceState *dev) gicv3_gicd_group_set(s, i); } } + s->gicd_no_migration_shift_bug = true; } static void arm_gic_common_linux_init(ARMLinuxBootIf *obj, diff --git a/hw/intc/arm_gicv3_kvm.c b/hw/intc/arm_gicv3_kvm.c index 0279b86cd970..5649cac46eea 100644 --- a/hw/intc/arm_gicv3_kvm.c +++ b/hw/intc/arm_gicv3_kvm.c @@ -164,6 +164,14 @@ static void kvm_dist_get_edge_trigger(GICv3State *s, uint32_t offset, uint32_t reg; int irq; + /* For the KVM GICv3, affinity routing is always enabled, and the first 2 + * GICD_ICFGR registers are always RAZ/WI. The corresponding + * functionality is replaced by GICR_ICFGR. It doesn't need to sync + * them. So it should increase the offset to skip GIC_INTERNAL irqs. + * This matches the for_each_dist_irq_reg() macro which also skips the + * first GIC_INTERNAL irqs. + */ + offset += (GIC_INTERNAL * 2) / 8; for_each_dist_irq_reg(irq, s->num_irq, 2) { kvm_gicd_access(s, offset, ®, false); reg = half_unshuffle32(reg >> 1); @@ -181,6 +189,14 @@ static void kvm_dist_put_edge_trigger(GICv3State *s, uint32_t offset, uint32_t reg; int irq; + /* For the KVM GICv3, affinity routing is always enabled, and the first 2 + * GICD_ICFGR registers are always RAZ/WI. The corresponding + * functionality is replaced by GICR_ICFGR. It doesn't need to sync + * them. So it should increase the offset to skip GIC_INTERNAL irqs. + * This matches the for_each_dist_irq_reg() macro which also skips the + * first GIC_INTERNAL irqs. + */ + offset += (GIC_INTERNAL * 2) / 8; for_each_dist_irq_reg(irq, s->num_irq, 2) { reg = *gic_bmp_ptr32(bmp, irq); if (irq % 32 != 0) { @@ -222,6 +238,15 @@ static void kvm_dist_getbmp(GICv3State *s, uint32_t offset, uint32_t *bmp) uint32_t reg; int irq; + /* For the KVM GICv3, affinity routing is always enabled, and the + * GICD_IGROUPR0/GICD_IGRPMODR0/GICD_ISENABLER0/GICD_ISPENDR0/ + * GICD_ISACTIVER0 registers are always RAZ/WI. The corresponding + * functionality is replaced by the GICR registers. It doesn't need to sync + * them. So it should increase the offset to skip GIC_INTERNAL irqs. + * This matches the for_each_dist_irq_reg() macro which also skips the + * first GIC_INTERNAL irqs. + */ + offset += (GIC_INTERNAL * 1) / 8; for_each_dist_irq_reg(irq, s->num_irq, 1) { kvm_gicd_access(s, offset, ®, false); *gic_bmp_ptr32(bmp, irq) = reg; @@ -235,6 +260,19 @@ static void kvm_dist_putbmp(GICv3State *s, uint32_t offset, uint32_t reg; int irq; + /* For the KVM GICv3, affinity routing is always enabled, and the + * GICD_IGROUPR0/GICD_IGRPMODR0/GICD_ISENABLER0/GICD_ISPENDR0/ + * GICD_ISACTIVER0 registers are always RAZ/WI. The corresponding + * functionality is replaced by the GICR registers. It doesn't need to sync + * them. So it should increase the offset and clroffset to skip GIC_INTERNAL + * irqs. This matches the for_each_dist_irq_reg() macro which also skips the + * first GIC_INTERNAL irqs. + */ + offset += (GIC_INTERNAL * 1) / 8; + if (clroffset != 0) { + clroffset += (GIC_INTERNAL * 1) / 8; + } + for_each_dist_irq_reg(irq, s->num_irq, 1) { /* If this bitmap is a set/clear register pair, first write to the * clear-reg to clear all bits before using the set-reg to write diff --git a/include/hw/intc/arm_gicv3_common.h b/include/hw/intc/arm_gicv3_common.h index bccdfe17c669..d75b49d55810 100644 --- a/include/hw/intc/arm_gicv3_common.h +++ b/include/hw/intc/arm_gicv3_common.h @@ -217,6 +217,7 @@ struct GICv3State { uint32_t revision; bool security_extn; bool irq_reset_nonsecure; + bool gicd_no_migration_shift_bug; int dev_fd; /* kvm device fd if backed by kvm vgic support */ Error *migration_blocker;