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Subject[PATCH] KVM: x86: Use div64_ul instead of do_div
Date
From: Changcheng Deng <deng.changcheng@zte.com.cn>

do_div() does a 64-by-32 division. Here the divisor is an unsigned long
which on some platforms is 64 bit wide. So use div64_ul instead of do_div
to avoid a possible truncation.

Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: Changcheng Deng <deng.changcheng@zte.com.cn>
---
arch/x86/kvm/lapic.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index c5028e6b0f96..3b629870632c 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -1707,7 +1707,7 @@ static void start_sw_tscdeadline(struct kvm_lapic *apic)
guest_tsc = kvm_read_l1_tsc(vcpu, rdtsc());

ns = (tscdeadline - guest_tsc) * 1000000ULL;
- do_div(ns, this_tsc_khz);
+ ns = div64_ul(ns, this_tsc_khz);

if (likely(tscdeadline > guest_tsc) &&
likely(ns > apic->lapic_timer.timer_advance_ns)) {
--
2.25.1
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