The patch below does not apply to the 4.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable@xxxxxxxxxxxxxxx>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 591d215afcc2f94e8e2c69a63c924c044677eb31 Mon Sep 17 00:00:00 2001 From: James Morse <james.morse@xxxxxxx> Date: Wed, 8 Jun 2016 17:24:45 +0100 Subject: [PATCH] KVM: arm/arm64: Stop leaking vcpu pid references kvm provides kvm_vcpu_uninit(), which amongst other things, releases the last reference to the struct pid of the task that was last running the vcpu. On arm64 built with CONFIG_DEBUG_KMEMLEAK, starting a guest with kvmtool, then killing it with SIGKILL results (after some considerable time) in: > cat /sys/kernel/debug/kmemleak > unreferenced object 0xffff80007d5ea080 (size 128): > comm "lkvm", pid 2025, jiffies 4294942645 (age 1107.776s) > hex dump (first 32 bytes): > 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ > backtrace: > [<ffff8000001b30ec>] create_object+0xfc/0x278 > [<ffff80000071da34>] kmemleak_alloc+0x34/0x70 > [<ffff80000019fa2c>] kmem_cache_alloc+0x16c/0x1d8 > [<ffff8000000d0474>] alloc_pid+0x34/0x4d0 > [<ffff8000000b5674>] copy_process.isra.6+0x79c/0x1338 > [<ffff8000000b633c>] _do_fork+0x74/0x320 > [<ffff8000000b66b0>] SyS_clone+0x18/0x20 > [<ffff800000085cb0>] el0_svc_naked+0x24/0x28 > [<ffffffffffffffff>] 0xffffffffffffffff On x86 kvm_vcpu_uninit() is called on the path from kvm_arch_destroy_vm(), on arm no equivalent call is made. Add the call to kvm_arch_vcpu_free(). Signed-off-by: James Morse <james.morse@xxxxxxx> Fixes: 749cf76c5a36 ("KVM: ARM: Initial skeleton to compile KVM support") Cc: <stable@xxxxxxxxxxxxxxx> # 3.10+ Acked-by: Marc Zyngier <marc.zyngier@xxxxxxx> Signed-off-by: Christoffer Dall <christoffer.dall@xxxxxxxxxx> diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c index 893941ec98dc..f1bde7c4e736 100644 --- a/arch/arm/kvm/arm.c +++ b/arch/arm/kvm/arm.c @@ -263,6 +263,7 @@ void kvm_arch_vcpu_free(struct kvm_vcpu *vcpu) kvm_timer_vcpu_terminate(vcpu); kvm_vgic_vcpu_destroy(vcpu); kvm_pmu_vcpu_destroy(vcpu); + kvm_vcpu_uninit(vcpu); kmem_cache_free(kvm_vcpu_cache, vcpu); } -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html