summaryrefslogtreecommitdiff
path: root/virt
diff options
context:
space:
mode:
authorXiubo Li <lixiubo@cmss.chinamobile.com>2016-06-15 18:00:33 +0800
committerSasha Levin <sasha.levin@oracle.com>2016-07-10 20:19:58 -0400
commit316515981206627bf97be37eca397234d604395d (patch)
tree2c5a24505ecca2abf7a8e09959cfab19d86831df /virt
parentaec2ddb9595f130759ca20c8f089e0361c95ca97 (diff)
kvm: Fix irq route entries exceeding KVM_MAX_IRQ_ROUTES
[ Upstream commit caf1ff26e1aa178133df68ac3d40815fed2187d9 ] These days, we experienced one guest crash with 8 cores and 3 disks, with qemu error logs as bellow: qemu-system-x86_64: /build/qemu-2.0.0/kvm-all.c:984: kvm_irqchip_commit_routes: Assertion `ret == 0' failed. And then we found one patch(bdf026317d) in qemu tree, which said could fix this bug. Execute the following script will reproduce the BUG quickly: irq_affinity.sh ======================================================================== vda_irq_num=25 vdb_irq_num=27 while [ 1 ] do for irq in {1,2,4,8,10,20,40,80} do echo $irq > /proc/irq/$vda_irq_num/smp_affinity echo $irq > /proc/irq/$vdb_irq_num/smp_affinity dd if=/dev/vda of=/dev/zero bs=4K count=100 iflag=direct dd if=/dev/vdb of=/dev/zero bs=4K count=100 iflag=direct done done ======================================================================== The following qemu log is added in the qemu code and is displayed when this bug reproduced: kvm_irqchip_commit_routes: max gsi: 1008, nr_allocated_irq_routes: 1024, irq_routes->nr: 1024, gsi_count: 1024. That's to say when irq_routes->nr == 1024, there are 1024 routing entries, but in the kernel code when routes->nr >= 1024, will just return -EINVAL; The nr is the number of the routing entries which is in of [1 ~ KVM_MAX_IRQ_ROUTES], not the index in [0 ~ KVM_MAX_IRQ_ROUTES - 1]. This patch fix the BUG above. Cc: stable@vger.kernel.org Signed-off-by: Xiubo Li <lixiubo@cmss.chinamobile.com> Signed-off-by: Wei Tang <tangwei@cmss.chinamobile.com> Signed-off-by: Zhang Zhuoyu <zhangzhuoyu@cmss.chinamobile.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Diffstat (limited to 'virt')
-rw-r--r--virt/kvm/kvm_main.c2
1 files changed, 1 insertions, 1 deletions
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index c2f87ff0061d..d93deb5ce4f2 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -2622,7 +2622,7 @@ static long kvm_vm_ioctl(struct file *filp,
if (copy_from_user(&routing, argp, sizeof(routing)))
goto out;
r = -EINVAL;
- if (routing.nr >= KVM_MAX_IRQ_ROUTES)
+ if (routing.nr > KVM_MAX_IRQ_ROUTES)
goto out;
if (routing.flags)
goto out;