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2020-10-29include: jhash/signal: Fix fall-through warnings for ClangGustavo A. R. Silva1-0/+2
In preparation to enable -Wimplicit-fallthrough for Clang, explicitly add break statements instead of letting the code fall through to the next case. This patch adds four break statements that, together, fix almost 40,000 warnings when building Linux 5.10-rc1 with Clang 12.0.0 and this[1] change reverted. Notice that in order to enable -Wimplicit-fallthrough for Clang, such change[1] is meant to be reverted at some point. So, this patch helps to move in that direction. Something important to mention is that there is currently a discrepancy between GCC and Clang when dealing with switch fall-through to empty case statements or to cases that only contain a break/continue/return statement[2][3][4]. Now that the -Wimplicit-fallthrough option has been globally enabled[5], any compiler should really warn on missing either a fallthrough annotation or any of the other case-terminating statements (break/continue/return/ goto) when falling through to the next case statement. Making exceptions to this introduces variation in case handling which may continue to lead to bugs, misunderstandings, and a general lack of robustness. The point of enabling options like -Wimplicit-fallthrough is to prevent human error and aid developers in spotting bugs before their code is even built/ submitted/committed, therefore eliminating classes of bugs. So, in order to really accomplish this, we should, and can, move in the direction of addressing any error-prone scenarios and get rid of the unintentional fallthrough bug-class in the kernel, entirely, even if there is some minor redundancy. Better to have explicit case-ending statements than continue to have exceptions where one must guess as to the right result. The compiler will eliminate any actual redundancy. [1] commit e2079e93f562c ("kbuild: Do not enable -Wimplicit-fallthrough for clang for now") [2] https://github.com/ClangBuiltLinux/linux/issues/636 [3] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91432 [4] https://godbolt.org/z/xgkvIh [5] commit a035d552a93b ("Makefile: Globally enable fall-through warning") Co-developed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-08-24treewide: Use fallthrough pseudo-keywordGustavo A. R. Silva1-13/+13
Replace the existing /* fall through */ comments and its variants with the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary fall-through markings when it is the case. [1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-08-12include/: replace HTTP links with HTTPS onesAlexander A. Klimov1-1/+1
Rationale: Reduces attack surface on kernel devs opening the links for MITM as HTTPS traffic is much harder to manipulate. Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Kees Cook <keescook@chromium.org> Link: http://lkml.kernel.org/r/20200726110117.16346-1-grandmaster@al2klimov.de Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-06-10Update my email addressJozsef Kadlecsik1-1/+1
It's better to use my kadlec@netfilter.org email address in the source code. I might not be able to use kadlec@blackhole.kfki.hu in the future. Signed-off-by: Jozsef Kadlecsik <kadlec@netfilter.org> Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
2017-07-17jhash: fix -Wimplicit-fallthrough warningsJakub Kicinski1-15/+14
GCC 7 added a new -Wimplicit-fallthrough warning. It's only enabled with W=1, but since linux/jhash.h is included in over hundred places (including other global headers) it seems worthwhile fixing this warning. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-04-03jhash: Update jhash_[321]words functions to use correct initvalAlexander Duyck1-6/+11
Looking over the implementation for jhash2 and comparing it to jhash_3words I realized that the two hashes were in fact very different. Doing a bit of digging led me to "The new jhash implementation" in which lookup2 was supposed to have been replaced with lookup3. In reviewing the patch I noticed that jhash2 had originally initialized a and b to JHASH_GOLDENRATIO and c to initval, but after the patch a, b, and c were initialized to initval + (length << 2) + JHASH_INITVAL. However the changes in jhash_3words simply replaced the initialization of a and b with JHASH_INITVAL. This change corrects what I believe was an oversight so that a, b, and c in jhash_3words all have the same value added consisting of initval + (length << 2) + JHASH_INITVAL so that jhash2 and jhash_3words will now produce the same hash result given the same inputs. Fixes: 60d509c823cca ("The new jhash implementation") Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-12-10The new jhash implementationJozsef Kadlecsik1-78/+105
The current jhash.h implements the lookup2() hash function by Bob Jenkins. However, lookup2() is outdated as Bob wrote a new hash function called lookup3(). The patch replaces the lookup2() implementation of the 'jhash*' functions with that of lookup3(). You can read a longer comparison of the two and other hash functions at http://burtleburtle.net/bob/hash/doobs.html. Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu> Acked-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-08-18Fix spelling mistake in jhashAnton Blanchard1-1/+1
Fix a spelling mistake. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2007-04-26[JHASH]: Use const in jhash2Patrick McHardy1-1/+1
Use const to avoid forcing users to cast const data. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-04-17Linux-2.6.12-rc2v2.6.12-rc2Linus Torvalds1-0/+143
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!