Zenghui Yu beb8e02541 KVM: arm64: vgic-v3: Retire all pending LPIs on vcpu destroy ... [ Upstream commit 969ce8b526 ] It's likely that the vcpu fails to handle all virtual interrupts if userspace decides to destroy it, leaving the pending ones stay in the ap_list. If the un-handled one is a LPI, its vgic_irq structure will be eventually leaked because of an extra refcount increment in vgic_queue_irq_unlock(). This was detected by kmemleak on almost every guest destroy, the backtrace is as follows: unreferenced object 0xffff80725aed5500 (size 128): comm "CPU 5/KVM", pid 40711, jiffies 4298024754 (age 166366.512s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 08 01 a9 73 6d 80 ff ff ...........sm... c8 61 ee a9 00 20 ff ff 28 1e 55 81 6c 80 ff ff .a... ..(.U.l... backtrace: [<000000004bcaa122>] kmem_cache_alloc_trace+0x2dc/0x418 [<0000000069c7dabb>] vgic_add_lpi+0x88/0x418 [<00000000bfefd5c5>] vgic_its_cmd_handle_mapi+0x4dc/0x588 [<00000000cf993975>] vgic_its_process_commands.part.5+0x484/0x1198 [<000000004bd3f8e3>] vgic_its_process_commands+0x50/0x80 [<00000000b9a65b2b>] vgic_mmio_write_its_cwriter+0xac/0x108 [<0000000009641ebb>] dispatch_mmio_write+0xd0/0x188 [<000000008f79d288>] __kvm_io_bus_write+0x134/0x240 [<00000000882f39ac>] kvm_io_bus_write+0xe0/0x150 [<0000000078197602>] io_mem_abort+0x484/0x7b8 [<0000000060954e3c>] kvm_handle_guest_abort+0x4cc/0xa58 [<00000000e0d0cd65>] handle_exit+0x24c/0x770 [<00000000b44a7fad>] kvm_arch_vcpu_ioctl_run+0x460/0x1988 [<0000000025fb897c>] kvm_vcpu_ioctl+0x4f8/0xee0 [<000000003271e317>] do_vfs_ioctl+0x160/0xcd8 [<00000000e7f39607>] ksys_ioctl+0x98/0xd8 Fix it by retiring all pending LPIs in the ap_list on the destroy path. p.s. I can also reproduce it on a normal guest shutdown. It is because userspace still send LPIs to vcpu (through KVM_SIGNAL_MSI ioctl) while the guest is being shutdown and unable to handle it. A little strange though and haven't dig further... Reviewed-by: James Morse <james.morse@arm.com> Signed-off-by: Zenghui Yu <yuzenghui@huawei.com> [maz: moved the distributor deallocation down to avoid an UAF splat] Signed-off-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20200414030349.625-2-yuzenghui@huawei.com Signed-off-by: Sasha Levin <sashal@kernel.org>		2020-10-01 13:17:56 +02:00
..
trace.h	KVM: arm/arm64: vgic: Use the appropriate TRACE_INCLUDE_PATH	2019-09-11 16:36:19 +01:00
vgic-debug.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234	2019-06-19 17:09:07 +02:00
vgic-init.c	KVM: arm64: vgic-v3: Retire all pending LPIs on vcpu destroy	2020-10-01 13:17:56 +02:00
vgic-irqfd.c	KVM: arm/arm64: vgic-irqfd: Implement kvm_arch_set_irq_inatomic	2019-08-18 18:38:54 +01:00
vgic-its.c	KVM: arm/arm64: vgic-its: Fix restoration of unmapped collections	2020-02-14 16:34:17 -05:00
vgic-kvm-device.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 174	2019-05-30 11:26:41 -07:00
vgic-mmio-v2.c	KVM: arm: vgic: Synchronize the whole guest on GIC{D,R}_I{S,C}ACTIVER read	2020-05-20 08:20:04 +02:00
vgic-mmio-v3.c	KVM: arm: vgic: Synchronize the whole guest on GIC{D,R}_I{S,C}ACTIVER read	2020-05-20 08:20:04 +02:00
vgic-mmio.c	KVM: arm: vgic: Synchronize the whole guest on GIC{D,R}_I{S,C}ACTIVER read	2020-05-20 08:20:04 +02:00
vgic-mmio.h	KVM: arm: vgic: Synchronize the whole guest on GIC{D,R}_I{S,C}ACTIVER read	2020-05-20 08:20:04 +02:00
vgic-v2.c	* s390: ioctl hardening, selftests	2019-09-18 09:49:13 -07:00
vgic-v3.c	KVM: arm/arm64: vgic: Don't rely on the wrong pending table	2019-12-13 08:43:00 +01:00
vgic-v4.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234	2019-06-19 17:09:07 +02:00
vgic.c	* s390: ioctl hardening, selftests	2019-09-18 09:49:13 -07:00
vgic.h	KVM: arm/arm64: vgic-its: Check the LPI translation cache on MSI injection	2019-08-18 18:38:53 +01:00