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diff --git a/Documentation/networking/netdev-FAQ.txt b/Documentation/networking/netdev-FAQ.txt new file mode 100644 index 000000000..0fe1c6e0d --- /dev/null +++ b/Documentation/networking/netdev-FAQ.txt @@ -0,0 +1,224 @@ + +Information you need to know about netdev +----------------------------------------- + +Q: What is netdev? + +A: It is a mailing list for all network-related Linux stuff. This includes + anything found under net/ (i.e. core code like IPv6) and drivers/net + (i.e. hardware specific drivers) in the Linux source tree. + + Note that some subsystems (e.g. wireless drivers) which have a high volume + of traffic have their own specific mailing lists. + + The netdev list is managed (like many other Linux mailing lists) through + VGER ( http://vger.kernel.org/ ) and archives can be found below: + + http://marc.info/?l=linux-netdev + http://www.spinics.net/lists/netdev/ + + Aside from subsystems like that mentioned above, all network-related Linux + development (i.e. RFC, review, comments, etc.) takes place on netdev. + +Q: How do the changes posted to netdev make their way into Linux? + +A: There are always two trees (git repositories) in play. Both are driven + by David Miller, the main network maintainer. There is the "net" tree, + and the "net-next" tree. As you can probably guess from the names, the + net tree is for fixes to existing code already in the mainline tree from + Linus, and net-next is where the new code goes for the future release. + You can find the trees here: + + http://git.kernel.org/?p=linux/kernel/git/davem/net.git + http://git.kernel.org/?p=linux/kernel/git/davem/net-next.git + +Q: How often do changes from these trees make it to the mainline Linus tree? + +A: To understand this, you need to know a bit of background information + on the cadence of Linux development. Each new release starts off with + a two week "merge window" where the main maintainers feed their new + stuff to Linus for merging into the mainline tree. After the two weeks, + the merge window is closed, and it is called/tagged "-rc1". No new + features get mainlined after this -- only fixes to the rc1 content + are expected. After roughly a week of collecting fixes to the rc1 + content, rc2 is released. This repeats on a roughly weekly basis + until rc7 (typically; sometimes rc6 if things are quiet, or rc8 if + things are in a state of churn), and a week after the last vX.Y-rcN + was done, the official "vX.Y" is released. + + Relating that to netdev: At the beginning of the 2-week merge window, + the net-next tree will be closed - no new changes/features. The + accumulated new content of the past ~10 weeks will be passed onto + mainline/Linus via a pull request for vX.Y -- at the same time, + the "net" tree will start accumulating fixes for this pulled content + relating to vX.Y + + An announcement indicating when net-next has been closed is usually + sent to netdev, but knowing the above, you can predict that in advance. + + IMPORTANT: Do not send new net-next content to netdev during the + period during which net-next tree is closed. + + Shortly after the two weeks have passed (and vX.Y-rc1 is released), the + tree for net-next reopens to collect content for the next (vX.Y+1) release. + + If you aren't subscribed to netdev and/or are simply unsure if net-next + has re-opened yet, simply check the net-next git repository link above for + any new networking-related commits. + + The "net" tree continues to collect fixes for the vX.Y content, and + is fed back to Linus at regular (~weekly) intervals. Meaning that the + focus for "net" is on stabilization and bugfixes. + + Finally, the vX.Y gets released, and the whole cycle starts over. + +Q: So where are we now in this cycle? + +A: Load the mainline (Linus) page here: + + http://git.kernel.org/?p=linux/kernel/git/torvalds/linux.git + + and note the top of the "tags" section. If it is rc1, it is early + in the dev cycle. If it was tagged rc7 a week ago, then a release + is probably imminent. + +Q: How do I indicate which tree (net vs. net-next) my patch should be in? + +A: Firstly, think whether you have a bug fix or new "next-like" content. + Then once decided, assuming that you use git, use the prefix flag, i.e. + + git format-patch --subject-prefix='PATCH net-next' start..finish + + Use "net" instead of "net-next" (always lower case) in the above for + bug-fix net content. If you don't use git, then note the only magic in + the above is just the subject text of the outgoing e-mail, and you can + manually change it yourself with whatever MUA you are comfortable with. + +Q: I sent a patch and I'm wondering what happened to it. How can I tell + whether it got merged? + +A: Start by looking at the main patchworks queue for netdev: + + http://patchwork.ozlabs.org/project/netdev/list/ + + The "State" field will tell you exactly where things are at with + your patch. + +Q: The above only says "Under Review". How can I find out more? + +A: Generally speaking, the patches get triaged quickly (in less than 48h). + So be patient. Asking the maintainer for status updates on your + patch is a good way to ensure your patch is ignored or pushed to + the bottom of the priority list. + +Q: How can I tell what patches are queued up for backporting to the + various stable releases? + +A: Normally Greg Kroah-Hartman collects stable commits himself, but + for networking, Dave collects up patches he deems critical for the + networking subsystem, and then hands them off to Greg. + + There is a patchworks queue that you can see here: + http://patchwork.ozlabs.org/bundle/davem/stable/?state=* + + It contains the patches which Dave has selected, but not yet handed + off to Greg. If Greg already has the patch, then it will be here: + http://git.kernel.org/cgit/linux/kernel/git/stable/stable-queue.git + + A quick way to find whether the patch is in this stable-queue is + to simply clone the repo, and then git grep the mainline commit ID, e.g. + + stable-queue$ git grep -l 284041ef21fdf2e + releases/3.0.84/ipv6-fix-possible-crashes-in-ip6_cork_release.patch + releases/3.4.51/ipv6-fix-possible-crashes-in-ip6_cork_release.patch + releases/3.9.8/ipv6-fix-possible-crashes-in-ip6_cork_release.patch + stable/stable-queue$ + +Q: I see a network patch and I think it should be backported to stable. + Should I request it via "stable@vger.kernel.org" like the references in + the kernel's Documentation/stable_kernel_rules.txt file say? + +A: No, not for networking. Check the stable queues as per above 1st to see + if it is already queued. If not, then send a mail to netdev, listing + the upstream commit ID and why you think it should be a stable candidate. + + Before you jump to go do the above, do note that the normal stable rules + in Documentation/stable_kernel_rules.txt still apply. So you need to + explicitly indicate why it is a critical fix and exactly what users are + impacted. In addition, you need to convince yourself that you _really_ + think it has been overlooked, vs. having been considered and rejected. + + Generally speaking, the longer it has had a chance to "soak" in mainline, + the better the odds that it is an OK candidate for stable. So scrambling + to request a commit be added the day after it appears should be avoided. + +Q: I have created a network patch and I think it should be backported to + stable. Should I add a "Cc: stable@vger.kernel.org" like the references + in the kernel's Documentation/ directory say? + +A: No. See above answer. In short, if you think it really belongs in + stable, then ensure you write a decent commit log that describes who + gets impacted by the bugfix and how it manifests itself, and when the + bug was introduced. If you do that properly, then the commit will + get handled appropriately and most likely get put in the patchworks + stable queue if it really warrants it. + + If you think there is some valid information relating to it being in + stable that does _not_ belong in the commit log, then use the three + dash marker line as described in Documentation/SubmittingPatches to + temporarily embed that information into the patch that you send. + +Q: Someone said that the comment style and coding convention is different + for the networking content. Is this true? + +A: Yes, in a largely trivial way. Instead of this: + + /* + * foobar blah blah blah + * another line of text + */ + + it is requested that you make it look like this: + + /* foobar blah blah blah + * another line of text + */ + +Q: I am working in existing code that has the former comment style and not the + latter. Should I submit new code in the former style or the latter? + +A: Make it the latter style, so that eventually all code in the domain of + netdev is of this format. + +Q: I found a bug that might have possible security implications or similar. + Should I mail the main netdev maintainer off-list? + +A: No. The current netdev maintainer has consistently requested that people + use the mailing lists and not reach out directly. If you aren't OK with + that, then perhaps consider mailing "security@kernel.org" or reading about + http://oss-security.openwall.org/wiki/mailing-lists/distros + as possible alternative mechanisms. + +Q: What level of testing is expected before I submit my change? + +A: If your changes are against net-next, the expectation is that you + have tested by layering your changes on top of net-next. Ideally you + will have done run-time testing specific to your change, but at a + minimum, your changes should survive an "allyesconfig" and an + "allmodconfig" build without new warnings or failures. + +Q: Any other tips to help ensure my net/net-next patch gets OK'd? + +A: Attention to detail. Re-read your own work as if you were the + reviewer. You can start with using checkpatch.pl, perhaps even + with the "--strict" flag. But do not be mindlessly robotic in + doing so. If your change is a bug-fix, make sure your commit log + indicates the end-user visible symptom, the underlying reason as + to why it happens, and then if necessary, explain why the fix proposed + is the best way to get things done. Don't mangle whitespace, and as + is common, don't mis-indent function arguments that span multiple lines. + If it is your first patch, mail it to yourself so you can test apply + it to an unpatched tree to confirm infrastructure didn't mangle it. + + Finally, go back and read Documentation/SubmittingPatches to be + sure you are not repeating some common mistake documented there. |