From: Changcheng Deng <deng.changcheng@xxxxxxxxxx> 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@xxxxxxxxxx> Signed-off-by: Changcheng Deng <deng.changcheng@xxxxxxxxxx> --- block/blk-throttle.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/block/blk-throttle.c b/block/blk-throttle.c index 39bb6e68a9a2..2db635d66617 100644 --- a/block/blk-throttle.c +++ b/block/blk-throttle.c @@ -1903,7 +1903,7 @@ static void throtl_downgrade_check(struct throtl_grp *tg) if (tg->bps[READ][LIMIT_LOW]) { bps = tg->last_bytes_disp[READ] * HZ; - do_div(bps, elapsed_time); + bps = div64_ul(bps, elapsed_time); if (bps >= tg->bps[READ][LIMIT_LOW]) tg->last_low_overflow_time[READ] = now; } -- 2.25.1