linux/arch/s390
Eric Dumazet aee636c480 bpf: do not use reciprocal divide
At first Jakub Zawadzki noticed that some divisions by reciprocal_divide
were not correct. (off by one in some cases)
http://www.wireshark.org/~darkjames/reciprocal-buggy.c

He could also show this with BPF:
http://www.wireshark.org/~darkjames/set-and-dump-filter-k-bug.c

The reciprocal divide in linux kernel is not generic enough,
lets remove its use in BPF, as it is not worth the pain with
current cpus.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Jakub Zawadzki <darkjames-ws@darkjames.pl>
Cc: Mircea Gherzan <mgherzan@gmail.com>
Cc: Daniel Borkmann <dxchgb@gmail.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Cc: Matt Evans <matt@ozlabs.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-15 17:02:08 -08:00
..
appldata s390: convert use of typedef ctl_table to struct ctl_table 2013-10-28 08:36:25 +01:00
boot s390/boot: Install bzImage as default kernel image 2013-11-15 14:08:36 +01:00
configs s390: add a couple of useful defconfigs 2013-10-24 17:17:14 +02:00
crypto crypto: s390 - Fix aes-xts parameter corruption 2013-11-28 22:25:16 +08:00
hypfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2013-09-05 08:50:26 -07:00
include s390/smp: improve setup of possible cpu mask 2013-12-18 17:35:18 +01:00
kernel s390/smp: improve setup of possible cpu mask 2013-12-18 17:35:18 +01:00
kvm Here are the 3.13 KVM changes. There was a lot of work on the PPC 2013-11-15 13:51:36 +09:00
lib s390/uaccess: add missing page table walk range check 2013-11-25 09:15:38 +01:00
math-emu s390: fix save and restore of the floating-point-control register 2013-10-24 17:17:11 +02:00
mm s390: handle pgtable_page_ctor() fail 2013-11-15 09:32:18 +09:00
net bpf: do not use reciprocal divide 2014-01-15 17:02:08 -08:00
oprofile Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux 2013-09-11 08:36:03 -07:00
pci s390/pci: obtain function handle in hotplug notifier 2013-12-30 11:28:47 +01:00
defconfig Update default configuration 2013-10-24 17:17:15 +02:00
Kbuild s390/pci: base support 2012-11-30 15:40:45 +01:00
Kconfig s390/smp: improve setup of possible cpu mask 2013-12-18 17:35:18 +01:00
Kconfig.debug Kconfig: consolidate CONFIG_DEBUG_STRICT_USER_COPY_CHECKS 2013-04-30 17:04:09 -07:00
Makefile s390: allow to set gcc -mtune flag 2013-10-31 09:54:01 +01:00