KVM: MCE: Send SRAR SIGBUS directly

Originally, SRAR SIGBUS is sent to QEMU-KVM via touching the poisoned
page. But commit 96054569190bdec375fe824e48ca1f4e3b53dd36 prevents the
signal from being sent. So now the signal is sent via
force_sig_info_fault directly.

[marcelo: use send_sig_info instead]

Reported-by: Dean Nelson <dnelson@redhat.com>
Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>

1 files changed, 10 insertions, 8 deletions

diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index eb65b9c5ea40..908ea5464a51 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -2251,22 +2251,24 @@ static int __direct_map(struct kvm_vcpu *vcpu, gpa_t v, int write,
         return pt_write;
 }
 
-static void kvm_send_hwpoison_signal(struct kvm *kvm, gfn_t gfn)
+static void kvm_send_hwpoison_signal(unsigned long address, struct task_struct *tsk)
 {
-        char buf[1];
-        void __user *hva;
-        int r;
+        siginfo_t info;
+
+        info.si_signo   = SIGBUS;
+        info.si_errno   = 0;
+        info.si_code    = BUS_MCEERR_AR;
+        info.si_addr    = (void __user *)address;
+        info.si_addr_lsb = PAGE_SHIFT;
 
-        /* Touch the page, so send SIGBUS */
-        hva = (void __user *)gfn_to_hva(kvm, gfn);
-        r = copy_from_user(buf, hva, 1);
+        send_sig_info(SIGBUS, &info, tsk);
 }
 
 static int kvm_handle_bad_page(struct kvm *kvm, gfn_t gfn, pfn_t pfn)
 {
         kvm_release_pfn_clean(pfn);
         if (is_hwpoison_pfn(pfn)) {
-                kvm_send_hwpoison_signal(kvm, gfn);
+                kvm_send_hwpoison_signal(gfn_to_hva(kvm, gfn), current);
                 return 0;
         } else if (is_fault_pfn(pfn))
                 return -EFAULT;