On 05.10.22 23:48, Jason A. Donenfeld wrote: > Rather than incurring a division or requesting too many random bytes for > the given range, use the prandom_u32_max() function, which only takes > the minimum required bytes from the RNG and avoids divisions. > > Signed-off-by: Jason A. Donenfeld <Jason@xxxxxxxxx> > --- > arch/x86/mm/pat/cpa-test.c | 4 +- > crypto/testmgr.c | 86 +++++++++---------- > drivers/block/drbd/drbd_receiver.c | 4 +- For the drbd part: Reviewed-by: Christoph Böhmwalder <christoph.boehmwalder@xxxxxxxxxx> > drivers/infiniband/core/cma.c | 2 +- > drivers/infiniband/hw/cxgb4/id_table.c | 4 +- > drivers/infiniband/hw/hns/hns_roce_ah.c | 5 +- > drivers/infiniband/ulp/rtrs/rtrs-clt.c | 3 +- > drivers/mmc/core/core.c | 4 +- > drivers/mmc/host/dw_mmc.c | 2 +- > drivers/mtd/nand/raw/nandsim.c | 4 +- > drivers/mtd/tests/mtd_nandecctest.c | 10 +-- > drivers/mtd/tests/stresstest.c | 17 +--- > drivers/mtd/ubi/debug.c | 2 +- > drivers/mtd/ubi/debug.h | 6 +- > drivers/net/ethernet/broadcom/cnic.c | 3 +- > .../chelsio/inline_crypto/chtls/chtls_io.c | 4 +- > drivers/net/hamradio/baycom_epp.c | 2 +- > drivers/net/hamradio/hdlcdrv.c | 2 +- > drivers/net/hamradio/yam.c | 2 +- > drivers/net/phy/at803x.c | 2 +- > .../broadcom/brcm80211/brcmfmac/p2p.c | 2 +- > .../net/wireless/intel/iwlwifi/mvm/mac-ctxt.c | 2 +- > drivers/scsi/fcoe/fcoe_ctlr.c | 4 +- > drivers/scsi/qedi/qedi_main.c | 2 +- > fs/ceph/inode.c | 2 +- > fs/ceph/mdsmap.c | 2 +- > fs/ext4/super.c | 7 +- > fs/f2fs/gc.c | 2 +- > fs/f2fs/segment.c | 8 +- > fs/ubifs/debug.c | 8 +- > fs/ubifs/lpt_commit.c | 14 +-- > fs/ubifs/tnc_commit.c | 2 +- > fs/xfs/libxfs/xfs_alloc.c | 2 +- > fs/xfs/libxfs/xfs_ialloc.c | 2 +- > fs/xfs/xfs_error.c | 2 +- > kernel/time/clocksource.c | 2 +- > lib/fault-inject.c | 2 +- > lib/find_bit_benchmark.c | 4 +- > lib/reed_solomon/test_rslib.c | 6 +- > lib/sbitmap.c | 4 +- > lib/test_list_sort.c | 2 +- > lib/test_vmalloc.c | 17 +--- > net/ceph/mon_client.c | 2 +- > net/ceph/osd_client.c | 2 +- > net/core/neighbour.c | 2 +- > net/core/pktgen.c | 43 +++++----- > net/core/stream.c | 2 +- > net/ipv4/igmp.c | 6 +- > net/ipv4/inet_connection_sock.c | 2 +- > net/ipv4/inet_hashtables.c | 2 +- > net/ipv6/addrconf.c | 8 +- > net/ipv6/mcast.c | 10 +-- > net/netfilter/ipvs/ip_vs_twos.c | 4 +- > net/packet/af_packet.c | 2 +- > net/sched/act_gact.c | 2 +- > net/sched/act_sample.c | 2 +- > net/sched/sch_netem.c | 4 +- > net/sctp/socket.c | 2 +- > net/sunrpc/cache.c | 2 +- > net/sunrpc/xprtsock.c | 2 +- > net/tipc/socket.c | 2 +- > net/xfrm/xfrm_state.c | 2 +- > 62 files changed, 173 insertions(+), 196 deletions(-) > [...] > diff --git a/drivers/block/drbd/drbd_receiver.c b/drivers/block/drbd/drbd_receiver.c > index af4c7d65490b..d8b1417dc503 100644 > --- a/drivers/block/drbd/drbd_receiver.c > +++ b/drivers/block/drbd/drbd_receiver.c > @@ -781,7 +781,7 @@ static struct socket *drbd_wait_for_connect(struct drbd_connection *connection, > > timeo = connect_int * HZ; > /* 28.5% random jitter */ > - timeo += (prandom_u32() & 1) ? timeo / 7 : -timeo / 7; > + timeo += prandom_u32_max(2) ? timeo / 7 : -timeo / 7; > > err = wait_for_completion_interruptible_timeout(&ad->door_bell, timeo); > if (err <= 0) > @@ -1004,7 +1004,7 @@ static int conn_connect(struct drbd_connection *connection) > drbd_warn(connection, "Error receiving initial packet\n"); > sock_release(s); > randomize: > - if (prandom_u32() & 1) > + if (prandom_u32_max(2)) > goto retry; > } > }[...] (Had to cut out most of the CC list because Google complains about "too many recipients"). -- Christoph Böhmwalder LINBIT | Keeping the Digital World Running DRBD HA — Disaster Recovery — Software defined Storage
