mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net.git/
synced 2026-04-01 22:37:41 -04:00
5d17af9eb2
Add a regression test for the divide-by-zero in rtsc_min() triggered when m2sm() converts a large m1 value (e.g. 32gbit) to a u64 scaled slope reaching 2^32. rtsc_min() stores the difference of two such u64 values (sm1 - sm2) in a u32 variable `dsm`, truncating 2^32 to zero and causing a divide-by-zero oops in the concave-curve intersection path. The test configures an HFSC class with m1=32gbit d=1ms m2=0bit, sends a packet to activate the class, waits for it to drain and go idle, then sends another packet to trigger reactivation through rtsc_min(). Signed-off-by: Xiang Mei <xmei5@asu.edu> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Reviewed-by: Victor Nogueira <victor@mojatatu.com> Link: https://patch.msgid.link/20260326204310.1549327-2-xmei5@asu.edu Signed-off-by: Jakub Kicinski <kuba@kernel.org>