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[PATCH net-next] ipvs: fix type warning in do_div() on 32 bit

To: davem@xxxxxxxxxxxxx
Subject: [PATCH net-next] ipvs: fix type warning in do_div() on 32 bit
Cc: netdev@xxxxxxxxxxxxxxx, edumazet@xxxxxxxxxx, pabeni@xxxxxxxxxx, Jakub Kicinski <kuba@xxxxxxxxxx>, horms@xxxxxxxxxxxx, ja@xxxxxx, pablo@xxxxxxxxxxxxx, kadlec@xxxxxxxxxxxxx, fw@xxxxxxxxx, jwiesner@xxxxxxx, lvs-devel@xxxxxxxxxxxxxxx, netfilter-devel@xxxxxxxxxxxxxxx, coreteam@xxxxxxxxxxxxx
From: Jakub Kicinski <kuba@xxxxxxxxxx>
Date: Mon, 12 Dec 2022 19:20:37 -0800
32 bit platforms without 64bit div generate the following warning:

net/netfilter/ipvs/ip_vs_est.c: In function 'ip_vs_est_calc_limits':
include/asm-generic/div64.h:222:35: warning: comparison of distinct pointer 
types lacks a cast
  222 |         (void)(((typeof((n)) *)0) == ((uint64_t *)0));  \
      |                                   ^~
net/netfilter/ipvs/ip_vs_est.c:694:17: note: in expansion of macro 'do_div'
  694 |                 do_div(val, loops);
      |                 ^~~~~~
include/asm-generic/div64.h:222:35: warning: comparison of distinct pointer 
types lacks a cast
  222 |         (void)(((typeof((n)) *)0) == ((uint64_t *)0));  \
      |                                   ^~
net/netfilter/ipvs/ip_vs_est.c:700:33: note: in expansion of macro 'do_div'
  700 |                                 do_div(val, min_est);
      |                                 ^~~~~~

first argument of do_div() should be unsigned. We can't just cast
as do_div() updates it as well, so we need an lval.
Make val unsigned in the first place, all paths check that the value
they assign to this variables are non-negative already.

Fixes: 705dd3444081 ("ipvs: use kthreads for stats estimation")
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
---
CC: horms@xxxxxxxxxxxx
CC: ja@xxxxxx
CC: pablo@xxxxxxxxxxxxx
CC: kadlec@xxxxxxxxxxxxx
CC: fw@xxxxxxxxx
CC: jwiesner@xxxxxxx
CC: lvs-devel@xxxxxxxxxxxxxxx
CC: netfilter-devel@xxxxxxxxxxxxxxx
CC: coreteam@xxxxxxxxxxxxx
---
 net/netfilter/ipvs/ip_vs_est.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/net/netfilter/ipvs/ip_vs_est.c b/net/netfilter/ipvs/ip_vs_est.c
index df56073bb282..ce2a1549b304 100644
--- a/net/netfilter/ipvs/ip_vs_est.c
+++ b/net/netfilter/ipvs/ip_vs_est.c
@@ -640,9 +640,10 @@ static int ip_vs_est_calc_limits(struct netns_ipvs *ipvs, 
int *chain_max)
        int i, loops, ntest;
        s32 min_est = 0;
        ktime_t t1, t2;
-       s64 diff, val;
        int max = 8;
        int ret = 1;
+       s64 diff;
+       u64 val;
 
        INIT_HLIST_HEAD(&chain);
        mutex_lock(&__ip_vs_mutex);
-- 
2.38.1


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