From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wr1-f65.google.com (mail-wr1-f65.google.com [209.85.221.65]) by mx.groups.io with SMTP id smtpd.web08.2070.1603229704502886372 for ; Tue, 20 Oct 2020 14:35:04 -0700 Authentication-Results: mx.groups.io; dkim=pass header.i=@gmail.com header.s=20161025 header.b=O/soOdml; spf=pass (domain: gmail.com, ip: 209.85.221.65, mailfrom: jpewhacker@gmail.com) Received: by mail-wr1-f65.google.com with SMTP id n6so4471718wrm.13 for ; Tue, 20 Oct 2020 14:35:04 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=h9/Hw0P33HTlL4x9xT5u2kpCjbaN7Sjc5yPVKMGFGiw=; b=O/soOdmlIHxIAHSapojhx4sLwgbzOf2QkcBODSvL3s5VTSlkfNHLpYTfH3tzDnWqds 4BKlk+hzTVSzLIaxO0FPl+ti4TySiktrictQniEwv4vue6pRT6JZM3ttgN6DeeyYQ+Ri IilymB4SOjjTdTGZYqSJWB+CqPNuE6AEm+7onHrurRF0ZcjZ2ZhSxCyuOfbbAAxgvpi4 zx5paP15vopUqI5Vsn39Ye626pJTNe/rdG3zTITOLc6Ath2vEKxUani9TC6JvxRUSfBY pwIcgwb8Zk4z3N5ewpHotqp3g5Ip82bd9cx8BT0oldhKccWQomRh8nWVudz1bqfyJajv ZnYw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=h9/Hw0P33HTlL4x9xT5u2kpCjbaN7Sjc5yPVKMGFGiw=; b=SlYRZd5f+vAWJRGnRgBUt6c/tWZ29A9wM7vbUA5sdKq/fdrKfvuF/WCNHibn2Uv8aa ZPZt8fIh+wmVHAeb4J/gx+v+d4X8cT2HDxNn9RQMYL3w0mjiaTCLwsXTnJKQ3YhHVRFq VFGhe6U3Md7xbeDCwteQWevgAYQTAATUoQPPw1iQymEy5fxKXga76dmHUO4xpgVsViZh Sy8FyBWb137bDyFkNAF2Wbfz4tQ41ZzX1byuwyqYCJe8l3KwDxlcz08/P3IlZtx9n0Xg GjrVSAoGYBNSNyOAkgSJl45VF1xHxODlIpRhGZ9hQcfpDFng1RZlotSrb0+ixhb+2PbJ XGVg== X-Gm-Message-State: AOAM533rxMNAYg6kVxbmklxJwEdHFwuLYApaJXhiRk1E8GO8EnLK8Nn/ 53voVPEGbLmZ5NColKy22FNKu6PquJ9iSbYbcFo= X-Google-Smtp-Source: ABdhPJx68iNTiv0X7+NWoKJHJkVE2fp5W6QHX8Ifj3f2xPK1T5xlGg1n2EgVRQRdlTZtL3PnYgd5hFeHeNY+/ZrNIyg= X-Received: by 2002:a7b:cb82:: with SMTP id m2mr15564wmi.56.1603229702977; Tue, 20 Oct 2020 14:35:02 -0700 (PDT) MIME-Version: 1.0 References: <20201020170326.14313-1-JPEWhacker@gmail.com> <9c52a04c-7184-8dfc-44e6-83a4cb7db2d0@gmail.com> In-Reply-To: From: "Joshua Watt" Date: Tue, 20 Oct 2020 16:34:52 -0500 Message-ID: Subject: Re: [docs][PATCH] kernel-dev: Add FAQ for how to use a vanilla kernel To: Bruce Ashfield Cc: "Robert Berger@yocto.user" , docs@lists.yoctoproject.org, Paul Barker Content-Type: text/plain; charset="UTF-8" On Tue, Oct 20, 2020 at 4:14 PM Bruce Ashfield wrote: > > On Tue, Oct 20, 2020 at 5:05 PM Robert Berger@yocto.user > wrote: > > > > Hi, > > > > On 20/10/2020 21:14, Joshua Watt wrote: > > > On Tue, Oct 20, 2020 at 12:03 PM Joshua Watt wrote: > > >> +.. note:: > > >> + You will notice that this is will still pull the kernel source from `the > > >> + Yocto Kernel git repo > > >> + `_, however it is > > >> + using the default value for :term:`KBRANCH` (e.g. ``"v5.8/standard/base"``) > > >> + which is an exact mirror of the upstream kernel. > > > > > > This is a lie. I thought it was the upstream mirror, but it's not. > > > v5.8/base is the mirror and this one has a few extra patches. > > > > > > > And exactly because only Bruce knows (most of the time) what is in all > > those funny branches why not use upstream (kernel.org) for a vanilla kernel? > > > > We are documented how the single linux-yocto repository can be used to > track tip (master), or any of the -stable upstream kernels > (/base), or the yocto specifics (/standard/base), > without needing to create 'x' recipes to do it. It is just a branch > switch away. > > Someone can always use upstream in their own kernel recipe, we are > just using this doc to describe what's in oe-core itself. There is a lot at play here; IMHO, using the branches Bruce maintains is actually the best option (if you can use it) because those branches are tested; I assume he's not making changes and diverging from upstream for the fun of it; the changes fix actual bugs. For example, I converted meta-rockchip to use the standard/base branches, and really haven't had to worry about it since; I have pretty high confidence those are going to continue to just work. meta-rockchip gets to freeload off of Bruce's hard work to upgrade the kernel and stays relatively up-to-date without much effort on my part :) OOTH, I get that people really just want to use the vanilla kernel (even though they probably *also* want the changes Bruce made), and it certainly "feels" like a better story if we can do that. As Bruce pointed out, you can do that by setting KBRANCH to the /base branch. I think the part that's missing there is that you also have to set SRCREV to a SHA1 on the branch, probably with some strange override? Maybe `SRCREV_machine_pn-linux-yocto = "..."` ? And, if you do that, I think the other problem is that `LINUX_VERSION` will then be wrong, so you might need to override that also. This also means that you don't get the latest versions "automatically" since you have to manually bump the SRCREV. In general it seems really easy for the linux-yocto recipes to get out of sync with your settings and cause confusion. We could maybe figure out a way to have a SRCREV for the upstream branch in the linux-yocto recipes, but it's weird and problematic to have a SRCREV pointing to something that's not tested (back the the point of why we have the "standard" branches in the first place, they are tested and work). > > Bruce > > > Regards, > > > > Robert > > > > -- > - Thou shalt not follow the NULL pointer, for chaos and madness await > thee at its end > - "Use the force Harry" - Gandalf, Star Trek II