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| author |   Paolo Bonzini <pbonzini@redhat.com> | 2016-06-01 14:09:18 +0200 |
|---|---|---|
| committer |   Radim Krčmář <rkrcmar@redhat.com> | 2016-06-02 17:38:50 +0200 |
| commit | b21629da120dd6145d14dbd6d028e1bba680a92b (patch) | |
| tree | 79c0c17b89a444477a39661cb9dc496b62ea662b /arch/x86 | |
| parent | KVM: Handle MSR_IA32_PERF_CTL (diff) | |
| download | linux-dev-b21629da120dd6145d14dbd6d028e1bba680a92b.tar.xz linux-dev-b21629da120dd6145d14dbd6d028e1bba680a92b.zip | |
kvm: x86: avoid warning on repeated KVM_SET_TSS_ADDR
Found by syzkaller:
WARNING: CPU: 3 PID: 15175 at arch/x86/kvm/x86.c:7705 __x86_set_memory_region+0x1dc/0x1f0 [kvm]()
CPU: 3 PID: 15175 Comm: a.out Tainted: G W 4.4.6-300.fc23.x86_64 #1
Hardware name: LENOVO 2325F51/2325F51, BIOS G2ET32WW (1.12 ) 05/30/2012
0000000000000286 00000000950899a7 ffff88011ab3fbf0 ffffffff813b542e
0000000000000000 ffffffffa0966496 ffff88011ab3fc28 ffffffff810a40f2
00000000000001fd 0000000000003000 ffff88014fc50000 0000000000000000
Call Trace:
[<ffffffff813b542e>] dump_stack+0x63/0x85
[<ffffffff810a40f2>] warn_slowpath_common+0x82/0xc0
[<ffffffff810a423a>] warn_slowpath_null+0x1a/0x20
[<ffffffffa09251cc>] __x86_set_memory_region+0x1dc/0x1f0 [kvm]
[<ffffffffa092521b>] x86_set_memory_region+0x3b/0x60 [kvm]
[<ffffffffa09bb61c>] vmx_set_tss_addr+0x3c/0x150 [kvm_intel]
[<ffffffffa092f4d4>] kvm_arch_vm_ioctl+0x654/0xbc0 [kvm]
[<ffffffffa091d31a>] kvm_vm_ioctl+0x9a/0x6f0 [kvm]
[<ffffffff81241248>] do_vfs_ioctl+0x298/0x480
[<ffffffff812414a9>] SyS_ioctl+0x79/0x90
[<ffffffff817a04ee>] entry_SYSCALL_64_fastpath+0x12/0x71
Testcase:
#include <unistd.h>
#include <sys/ioctl.h>
#include <fcntl.h>
#include <string.h>
#include <linux/kvm.h>
long r[8];
int main()
{
memset(r, -1, sizeof(r));
r[2] = open("/dev/kvm", O_RDONLY|O_TRUNC);
r[3] = ioctl(r[2], KVM_CREATE_VM, 0x0ul);
r[5] = ioctl(r[3], KVM_SET_TSS_ADDR, 0x20000000ul);
r[7] = ioctl(r[3], KVM_SET_TSS_ADDR, 0x20000000ul);
return 0;
}
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Diffstat (limited to 'arch/x86')
| -rw-r--r-- | arch/x86/kvm/x86.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index d0a5b4b4e64d..990929bbeb50 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -7816,7 +7816,7 @@ int __x86_set_memory_region(struct kvm *kvm, int id, gpa_t gpa, u32 size) slot = id_to_memslot(slots, id); if (size) { - if (WARN_ON(slot->npages)) + if (slot->npages) return -EEXIST; /* |