* [PATCH 3/3] x86/tsc: Use div64_64 instead of do_div()
@ 2024-04-28 17:32 Jules Irenge
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From: Jules Irenge @ 2024-04-28 17:32 UTC (permalink / raw)
To: mingo; +Cc: tglx, bp, x86, hpa, peterz, rdunlap, linux-kernel
do_div() truncates a u64 divisor to 32 bit.
This can lead to non-zero being truncated to zero for division.
Fix coccinelle warning
WARNING: do_div() does a 64-by-32 division, please consider using div64_64 instead
Signed-off-by: Jules Irenge <jbi.octave@gmail.com>
---
arch/x86/kernel/tsc.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c
index 2ed154a2642c..9106069f18b2 100644
--- a/arch/x86/kernel/tsc.c
+++ b/arch/x86/kernel/tsc.c
@@ -401,7 +401,7 @@ static unsigned long calc_pmtimer_ref(u64 deltatsc, u64 pm1, u64 pm2)
pm2 -= pm1;
tmp = pm2 * 1000000000LL;
do_div(tmp, PMTMR_TICKS_PER_SEC);
- do_div(deltatsc, tmp);
+ div64_u64(deltatsc, tmp);
return (unsigned long) deltatsc;
}
--
2.43.2
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