Re: [clear_page] 0ad07c8104 BUG: unable to handle kernel NULL pointer dereference at 0000000000000040

From: Fengguang Wu
Date: Sun Feb 19 2017 - 22:04:04 EST

Hi Borislav,

On Sun, Feb 19, 2017 at 02:50:19PM +0100, Borislav Petkov wrote:
On Sun, Feb 19, 2017 at 09:06:51AM +0800, Fengguang Wu wrote:
Yes if we add it as a line below the branch URL, it could be a time saver.


Since it's hard to teach ALL people about the rule, it'd be best if we
can work w/o any rules -- unless you want to be accurate&helpful or to
customize test behaviors.

Since we already tested the original patch/commit (hence the report),
we should know where the fixup should be applied to. And it'd be
reasonably easy to tell whether the fix is incremental or a
replacement -- just try git-am onto the original commit first, if
failed, continue to try the parent commit. For old bugs the fix could
be against linus/master or linux-next/master, which could be tried too.

Makes sense.

Yes, that'd be most convenient. In general the email interface could
be something like this:

# "key: value" fields; if you Re: to an earlier bug report, they can be auto retrieved
compiler: gcc-6 # optional
base-commit: v4.10-rc8 # the robot knows kernel commits from hundreds of public git trees
the patch
attach kconfig files

Yap, just stick those rules somewhere on a website.

OK, will do when the feature is ready. According to Xiaolong, the
automated test-of-fixup-patches feature is already in our plan.

For introductions of the now-working build/boot test services and
instructions on customization, we could probably add some markdown
document under

Philip/Ying, what do you think? I can draft it.

Btw, this is not only useful for a follow-on, fix patch but also for
initial test request. For example, I want to backport patch to stable
and would like to run it on a bunch of kernels:

base-commit: v4.4-stable, v4.9-stable, ...

i.e., a list of trees to apply it to. I believe people might like this a

Or, for example, a patch touching a bunch of arches and author doesn't
necessarily have access to all those different toolchains. Shoot a mail
to the 0day bot:

base-commit: linus/master
arch: x86_64, powerpc, sparc, ...

Would be very useful too.

We actually already test LKML patch in that way (Xiaolong maintains
this feature). Nevertheless if developers specify "base-commit:" it
could help eliminate the guessing works by the dumb robot. We'll
appreciate if the "base-commit:" or "base-patchid:" tags are listed
in the patches, especially in some non-obvious situations.

Such tags could be regarded as "explicit" test requests, where we could
send "BUILD COMPLETE" emails as a response (comparing to our normal
LKML patch tests, which only build regressions will trigger an email

Anyway, just a couple of ideas.

What would also be cool if you guys had a 0day bot howto with all those
things we should pay attention to and we can go and look up.

OK. Your ideas are very welcome, thanks!