KVM: fix rcu usage in init_rmode_* functions

fix:
[ 3494.671786] stack backtrace:
[ 3494.671789] Pid: 10527, comm: qemu-system-x86 Not tainted 2.6.38-rc6+ #23
[ 3494.671790] Call Trace:
[ 3494.671796]  [] ? lockdep_rcu_dereference+0x9d/0xa5
[ 3494.671826]  [] ? kvm_memslots+0x6b/0x73 [kvm]
[ 3494.671834]  [] ? gfn_to_memslot+0x16/0x4f [kvm]
[ 3494.671843]  [] ? gfn_to_hva+0x16/0x27 [kvm]
[ 3494.671851]  [] ? kvm_write_guest_page+0x31/0x83 [kvm]
[ 3494.671861]  [] ? kvm_clear_guest_page+0x1a/0x1c [kvm]
[ 3494.671867]  [] ? vmx_set_tss_addr+0x83/0x122 [kvm_intel]

and:
[ 8328.789599] stack backtrace:
[ 8328.789601] Pid: 18736, comm: qemu-system-x86 Not tainted 2.6.38-rc6+ #23
[ 8328.789603] Call Trace:
[ 8328.789609]  [] ? lockdep_rcu_dereference+0x9d/0xa5
[ 8328.789621]  [] ? kvm_memslots+0x6b/0x73 [kvm]
[ 8328.789628]  [] ? gfn_to_memslot+0x16/0x4f [kvm]
[ 8328.789635]  [] ? gfn_to_hva+0x16/0x27 [kvm]
[ 8328.789643]  [] ? kvm_write_guest_page+0x31/0x83 [kvm]
[ 8328.789699]  [] ? kvm_clear_guest_page+0x1a/0x1c [kvm]
[ 8328.789713]  [] ? vmx_create_vcpu+0x316/0x3c8 [kvm_intel]

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
This commit is contained in:
Xiao Guangrong 2011-03-09 15:41:04 +08:00 committed by Marcelo Tosatti
parent 1aa8ceef03
commit 40dcaa9f69
1 changed files with 8 additions and 4 deletions

View File

@ -2397,11 +2397,12 @@ static bool guest_state_valid(struct kvm_vcpu *vcpu)
static int init_rmode_tss(struct kvm *kvm)
{
gfn_t fn = rmode_tss_base(kvm) >> PAGE_SHIFT;
gfn_t fn;
u16 data = 0;
int ret = 0;
int r;
int r, idx, ret = 0;
idx = srcu_read_lock(&kvm->srcu);
fn = rmode_tss_base(kvm) >> PAGE_SHIFT;
r = kvm_clear_guest_page(kvm, fn, 0, PAGE_SIZE);
if (r < 0)
goto out;
@ -2425,12 +2426,13 @@ static int init_rmode_tss(struct kvm *kvm)
ret = 1;
out:
srcu_read_unlock(&kvm->srcu, idx);
return ret;
}
static int init_rmode_identity_map(struct kvm *kvm)
{
int i, r, ret;
int i, idx, r, ret;
pfn_t identity_map_pfn;
u32 tmp;
@ -2445,6 +2447,7 @@ static int init_rmode_identity_map(struct kvm *kvm)
return 1;
ret = 0;
identity_map_pfn = kvm->arch.ept_identity_map_addr >> PAGE_SHIFT;
idx = srcu_read_lock(&kvm->srcu);
r = kvm_clear_guest_page(kvm, identity_map_pfn, 0, PAGE_SIZE);
if (r < 0)
goto out;
@ -2460,6 +2463,7 @@ static int init_rmode_identity_map(struct kvm *kvm)
kvm->arch.ept_identity_pagetable_done = true;
ret = 1;
out:
srcu_read_unlock(&kvm->srcu, idx);
return ret;
}