Linux 5.12's very bad, double ungood day

Posted Mar 9, 2021 15:12 UTC (Tue) by Cyberax (✭ supporter ✭, #52523)
In reply to: Linux 5.12's very bad, double ungood day by pizza
Parent article: Linux 5.12's very bad, double ungood day

Linus can issue a pre-RC (alpha1?) to give time to run the tests, a day before the actual RC.

Linux 5.12's very bad, double ungood day

Posted Mar 9, 2021 15:22 UTC (Tue) by geert (subscriber, #98403) [Link] (1 responses)

That's why we linux-next, which is used for lots of automated integration tests

$ git tag --contains 48d15436fde6
next-20210128
next-20210129
next-20210201
next-20210202
next-20210203
next-20210204
next-20210205
next-20210208
next-20210209
next-20210210
next-20210211
next-20210212
next-20210215
next-20210216
next-20210217
next-20210218
next-20210219
next-20210222
next-20210223
next-20210224
next-20210225
next-20210226
next-20210301
next-20210302
next-20210303
next-20210304
next-20210305
next-20210309
v5.12-rc1
v5.12-rc1-dontuse
v5.12-rc2

Three weeks passed between the buggy commit entering linux-next and upstream.

Linux 5.12's very bad, double ungood day

Posted Mar 9, 2021 15:35 UTC (Tue) by pizza (subscriber, #46) [Link]

> That's why we linux-next, which is used for lots of automated integration tests
> Three weeks passed between the buggy commit entering linux-next and upstream.

So the "problem" here isn't that nothing was being tested, it's just that none of the tests run during this interval window caught this particular issue. It's also not clear that there was even a test out there that could have caught this, except by pure happenstance.

But that's the reality of software work; a bug turns up, write a test to catch it (and hopefully others of the same class), add it to the test suite (which runs as often as your available resources allow) .... and repeat endlessly.

Linux 5.12's very bad, double ungood day

Posted Mar 9, 2021 15:25 UTC (Tue) by pizza (subscriber, #46) [Link] (8 responses)

... okay, so rename "rc1" to "alpha1" , "rc2" to "alpha2" and so forth. Problem solved?

Not that it will stop folks complaining when "5.32-alpha0-rc4-pre3" fails to boot on their production system, obviously because it should have been tested first, and we need a pre-pre-pre-pre-pre release snapshot to start testing against.

Linux 5.12's very bad, double ungood day

Posted Mar 9, 2021 15:26 UTC (Tue) by Cyberax (✭ supporter ✭, #52523) [Link] (6 responses)

Kinda. You'll have alphaN that is released before rcN, and the distinction is that alphaN is meant only for automatic testing on throwaway hardware.

Linux 5.12's very bad, double ungood day

Posted Mar 9, 2021 17:47 UTC (Tue) by Wol (subscriber, #4433) [Link] (5 responses)

And how many people will ignore that (or be unaware) and load alphaN on their production server anyway?

Horse to water and all that ...

Cheers,
Wol

Linux 5.12's very bad, double ungood day

Posted Mar 9, 2021 19:55 UTC (Tue) by mathstuf (subscriber, #69389) [Link]

Crazy idea: require kernel.testing.alpha=5.20.0-alpha1 on the cmdline to boot such an alpha kernel. Reject such an option in non-alpha kernels (including development kernels; the tagged release would require this code and not otherwise).

But this kind of one-off code is annoying to test itself and someone will script adding it to their boot command lines anyways.

Linux 5.12's very bad, double ungood day

Posted Mar 10, 2021 21:58 UTC (Wed) by sjj (guest, #2020) [Link] (3 responses)

How many people run non-distro kernels these days, especially in production? If you do that with an rc kernel, you certainly deserve whatever pieces are left of your data.

I don’t think I’ve built a kernel in 10 years, or maybe that one time 7-8 years ago.

Linux 5.12's very bad, double ungood day

Posted Mar 10, 2021 22:22 UTC (Wed) by roc (subscriber, #30627) [Link] (1 responses)

In the past, when reporting a bug in a release kernel, people have asked me to install some random kernel revision to see if the bug is still present with it. If we should never do that, people should stop asking for it.

Linux 5.12's very bad, double ungood day

Posted Mar 11, 2021 8:43 UTC (Thu) by pbonzini (subscriber, #60935) [Link]

You weren't supposed to do that in production though. Also, answering "sorry I can't" is perfectly valid. :)

Linux 5.12's very bad, double ungood day

Posted Mar 10, 2021 23:20 UTC (Wed) by Wol (subscriber, #4433) [Link]

> I don’t think I’ve built a kernel in 10 years, or maybe that one time 7-8 years ago.

You clearly don't run gentoo :-)

Cheers,
Wol

Linux 5.12's very bad, double ungood day

Posted May 2, 2021 2:58 UTC (Sun) by pizza (subscriber, #46) [Link]

> Not that it will stop folks complaining when "5.32-alpha0-rc4-pre3" fails to boot on their production system, obviously because it should have been tested first, and we need a pre-pre-pre-pre-pre release snapshot to start testing against.

I saw this scroll by when I upgraded this system to Fedora 34:

$ rpm -q icedtea-web
icedtea-web-2.0.0-pre.0.3.alpha16.patched1.fc34.3.x86_64