From 2f8b1ad2228a7f1f1e2458864f4bfc1cbdf511ed Mon Sep 17 00:00:00 2001 From: Gavin Shan Date: Fri, 27 Jan 2023 07:54:50 +0800 Subject: KVM: arm64: Allow no running vcpu on restoring vgic3 LPI pending status We don't have a running VCPU context to restore vgic3 LPI pending status due to command KVM_DEV_ARM_{VGIC_GRP_CTRL, ITS_RESTORE_TABLES} on KVM device "kvm-arm-vgic-its". Use vgic_write_guest_lock() to restore vgic3 LPI pending status. Signed-off-by: Gavin Shan Reviewed-by: Oliver Upton Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20230126235451.469087-4-gshan@redhat.com --- Documentation/virt/kvm/api.rst | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) (limited to 'Documentation') diff --git a/Documentation/virt/kvm/api.rst b/Documentation/virt/kvm/api.rst index dbed78a9c31b..25e9095596af 100644 --- a/Documentation/virt/kvm/api.rst +++ b/Documentation/virt/kvm/api.rst @@ -8070,9 +8070,11 @@ considering the state as complete. VMM needs to ensure that the dirty state is final and avoid missing dirty pages from another ioctl ordered after the bitmap collection. -NOTE: One example of using the backup bitmap is saving arm64 vgic/its -tables through KVM_DEV_ARM_{VGIC_GRP_CTRL, ITS_SAVE_TABLES} command on -KVM device "kvm-arm-vgic-its" when dirty ring is enabled. +NOTE: Multiple examples of using the backup bitmap: (1) save vgic/its +tables through command KVM_DEV_ARM_{VGIC_GRP_CTRL, ITS_SAVE_TABLES} on +KVM device "kvm-arm-vgic-its". (2) restore vgic/its tables through +command KVM_DEV_ARM_{VGIC_GRP_CTRL, ITS_RESTORE_TABLES} on KVM device +"kvm-arm-vgic-its". VGICv3 LPI pending status is restored. 8.30 KVM_CAP_XEN_HVM -------------------- -- cgit v1.2.3 From 6028acbe3a5f2119a2a6ddd3e06453c87c09cae0 Mon Sep 17 00:00:00 2001 From: Gavin Shan Date: Fri, 27 Jan 2023 07:54:51 +0800 Subject: KVM: arm64: Allow no running vcpu on saving vgic3 pending table We don't have a running VCPU context to save vgic3 pending table due to KVM_DEV_ARM_VGIC_{GRP_CTRL, SAVE_PENDING_TABLES} command on KVM device "kvm-arm-vgic-v3". The unknown case is caught by kvm-unit-tests. # ./kvm-unit-tests/tests/its-pending-migration WARNING: CPU: 120 PID: 7973 at arch/arm64/kvm/../../../virt/kvm/kvm_main.c:3325 \ mark_page_dirty_in_slot+0x60/0xe0 : mark_page_dirty_in_slot+0x60/0xe0 __kvm_write_guest_page+0xcc/0x100 kvm_write_guest+0x7c/0xb0 vgic_v3_save_pending_tables+0x148/0x2a0 vgic_set_common_attr+0x158/0x240 vgic_v3_set_attr+0x4c/0x5c kvm_device_ioctl+0x100/0x160 __arm64_sys_ioctl+0xa8/0xf0 invoke_syscall.constprop.0+0x7c/0xd0 el0_svc_common.constprop.0+0x144/0x160 do_el0_svc+0x34/0x60 el0_svc+0x3c/0x1a0 el0t_64_sync_handler+0xb4/0x130 el0t_64_sync+0x178/0x17c Use vgic_write_guest_lock() to save vgic3 pending table. Reported-by: Zenghui Yu Signed-off-by: Gavin Shan Reviewed-by: Oliver Upton Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20230126235451.469087-5-gshan@redhat.com --- Documentation/virt/kvm/api.rst | 4 +++- arch/arm64/kvm/vgic/vgic-v3.c | 2 +- 2 files changed, 4 insertions(+), 2 deletions(-) (limited to 'Documentation') diff --git a/Documentation/virt/kvm/api.rst b/Documentation/virt/kvm/api.rst index 25e9095596af..5006901ad6c6 100644 --- a/Documentation/virt/kvm/api.rst +++ b/Documentation/virt/kvm/api.rst @@ -8074,7 +8074,9 @@ NOTE: Multiple examples of using the backup bitmap: (1) save vgic/its tables through command KVM_DEV_ARM_{VGIC_GRP_CTRL, ITS_SAVE_TABLES} on KVM device "kvm-arm-vgic-its". (2) restore vgic/its tables through command KVM_DEV_ARM_{VGIC_GRP_CTRL, ITS_RESTORE_TABLES} on KVM device -"kvm-arm-vgic-its". VGICv3 LPI pending status is restored. +"kvm-arm-vgic-its". VGICv3 LPI pending status is restored. (3) save +vgic3 pending table through KVM_DEV_ARM_VGIC_{GRP_CTRL, SAVE_PENDING_TABLES} +command on KVM device "kvm-arm-vgic-v3". 8.30 KVM_CAP_XEN_HVM -------------------- diff --git a/arch/arm64/kvm/vgic/vgic-v3.c b/arch/arm64/kvm/vgic/vgic-v3.c index 3dab286ed23f..684bdfaad4a9 100644 --- a/arch/arm64/kvm/vgic/vgic-v3.c +++ b/arch/arm64/kvm/vgic/vgic-v3.c @@ -434,7 +434,7 @@ int vgic_v3_save_pending_tables(struct kvm *kvm) else val &= ~(1 << bit_nr); - ret = kvm_write_guest_lock(kvm, ptr, &val, 1); + ret = vgic_write_guest_lock(kvm, ptr, &val, 1); if (ret) goto out; } -- cgit v1.2.3