git.ipfire.org Git - thirdparty/kernel/stable-queue.git/blob

   1 From 7321f47eada53a395fb3086d49297eebb19e8e58 Mon Sep 17 00:00:00 2001
   2 From: Vitaly Kuznetsov <vkuznets@redhat.com>
   3 Date: Tue, 22 Feb 2022 16:46:41 +0100
   4 Subject: KVM: x86: hyper-v: Fix the maximum number of sparse banks for XMM fast TLB flush hypercalls
   5
   6 From: Vitaly Kuznetsov <vkuznets@redhat.com>
   7
   8 commit 7321f47eada53a395fb3086d49297eebb19e8e58 upstream.
   9
  10 When TLB flush hypercalls (HVCALL_FLUSH_VIRTUAL_ADDRESS_{LIST,SPACE}_EX are
  11 issued in 'XMM fast' mode, the maximum number of allowed sparse_banks is
  12 not 'HV_HYPERCALL_MAX_XMM_REGISTERS - 1' (5) but twice as many (10) as each
  13 XMM register is 128 bit long and can hold two 64 bit long banks.
  14
  15 Cc: stable@vger.kernel.org # 5.14.x
  16 Fixes: 5974565bc26d ("KVM: x86: kvm_hv_flush_tlb use inputs from XMM registers")
  17 Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
  18 Message-Id: <20220222154642.684285-4-vkuznets@redhat.com>
  19 Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
  20 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  21 ---
  22  arch/x86/kvm/hyperv.c |    3 ++-
  23  1 file changed, 2 insertions(+), 1 deletion(-)
  24
  25 --- a/arch/x86/kvm/hyperv.c
  26 +++ b/arch/x86/kvm/hyperv.c
  27 @@ -1820,7 +1820,8 @@ static u64 kvm_hv_flush_tlb(struct kvm_v
  28
  29                 if (!all_cpus) {
  30                         if (hc->fast) {
  31 -                               if (sparse_banks_len > HV_HYPERCALL_MAX_XMM_REGISTERS - 1)
  32 +                               /* XMM0 is already consumed, each XMM holds two sparse banks. */
  33 +                               if (sparse_banks_len > 2 * (HV_HYPERCALL_MAX_XMM_REGISTERS - 1))
  34                                         return HV_STATUS_INVALID_HYPERCALL_INPUT;
  35                                 for (i = 0; i < sparse_banks_len; i += 2) {
  36                                         sparse_banks[i] = sse128_lo(hc->xmm[i / 2 + 1]);