> themselves in this strange edge case, this is enough for the LLM to scrap=
e
> and give a solution :)
>
> Thanks for the hints Warner.  Not sure why it didnt "just work" but it
> works with this added step.
>

OK. That tells me that the new code that supposedly creates compatible
old-ZFS images doesn't in some minor, usually trivial way, but that in this
case causes the old boot loader to not be able to load it.

Copying the 12.x bootloader should just work with 11.x kernels. The handoff
protocols are the same (ish, there's one difference with UEFI that would
bite you there, but this is BIOS).

Warner


>
>     ---Mike
>
> FreeBSD/x86 ZFS enabled bootstrap loader, Revision 1.1
>>
>> (Tues Oct 10:24:17 EDT 2018 user@hostname)
>> panic: free: guard2 fail @ 0xbf153040 + 2061 from unknown:0
>> --> Press a key on the console to reboot <--
>>
>
> This is a memory corruption bug. You'll need to find what's corrupting
> memory and make it stop.
>
> I imagine this might be a small incompatibility with OpenZFS or just
> a bug in what openZFS is generating on the releng13 server.
>
> What version is the boot loader? There's been like 6 years of fixes and
> churn since the date above? Maybe the latest on RELENG_11 for it
> if you are still running 11.2-stable.
>
> Any chance you can use the stable/13 or stable/14 loaders? 11 is really
> not supported anymore and hasn't been for quite some time. I have no
> time for it beyond this quick peek.
>
>
>

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<div dir=3D"ltr"><div dir=3D"ltr"><br></div><br><div class=3D"gmail_quote">=
<div dir=3D"ltr" class=3D"gmail_attr">On Fri, May 17, 2024 at 1:52=E2=80=AF=
PM mike tancsa &lt;<a href=3D"mailto:mike@sentex.net">mike@sentex.net</a>&g=
t; wrote:<br></div><blockquote class=3D"gmail_quote" style=3D"margin:0px 0p=
x 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><u></u=
>

 =20
   =20
 =20
  <div>
    <div>On 5/16/2024 10:38 AM, Warner Losh
      wrote:<br>
    </div>
    <blockquote type=3D"cite">
     =20
      <div dir=3D"ltr">
        <div dir=3D"ltr"><br>
        </div>
        <br>
        <div class=3D"gmail_quote">
          <div dir=3D"ltr" class=3D"gmail_attr">On Thu, May 16, 2024 at
            8:14=E2=80=AFAM mike tancsa &lt;<a href=3D"mailto:mike@sentex.n=
et" target=3D"_blank">mike@sentex.net</a>&gt;
            wrote:<br>
          </div>
          <blockquote class=3D"gmail_quote" style=3D"margin:0px 0px 0px 0.8=
ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">I
            have a strange edge case I am trying to work around.=C2=A0 I ha=
ve
            a <br>
            customer&#39;s legacy VM which is RELENG_11 on ZFS.=C2=A0 There=
 is
            some <br>
            corruption that wont clear on a bunch of directories, so I
            want to <br>
            re-create it from backups. I have done this many times in
            the past but <br>
            this one is giving me grief. Normally I do something like
            this on my <br>
            backup server (RELENG_13)<br>
            <br>
            truncate -s 100G file.raw<br>
            mdconfig -f file.raw<br>
            gpart create -s gpt md0<br>
            gpart add -t freebsd-boot -s 512k md0<br>
            gpart bootcode -b /boot/pmbr -p /boot/gptzfsboot -i 1 md0<br>
            gpart add -t freebsd-swap -s 2G md0<br>
            gpart add -t freebsd-zfs md0<br>
            zpool create -d -f -o altroot=3D/mnt2 -o
            feature@lz4_compress=3Denabled -o <br>
            cachefile=3D/var/tmp/zpool.cache myZFSPool /dev/md0p3<br>
          </blockquote>
          <div><br>
          </div>
          <div>I&#39;m surprised you don&#39;t specifically create compatib=
ility
            with some older</div>
          <div>standard and then maybe add compression. But I&#39;d start
            there: create</div>
          <div>one that doesn&#39;t use lz4_compress (it&#39;s not read-onl=
y
            compatible,</div>
          <div>meaning the old boot loader has to 100% implement it
            faithfully).</div>
        </div>
      </div>
    </blockquote>
    <p>Hi Warner,</p>
    <p>=C2=A0=C2=A0=C2=A0 I though -d would make the LCD. But looking at th=
e updated
      man pages for zpool create, I didnt realize there are these
      handy-dandy files with all the supported features!</p>
    <p>Trying with=C2=A0</p>
    <p>=C2=A0=C2=A0=C2=A0 zpool create -o
      compatibility=3D/usr/share/zfs/compatibility.d/freebsd-11.2 -o
      altroot=3D/mnt2=C2=A0 -o cachefile=3D/var/tmp/zpool.cache myZFSPool
      /dev/md0p3</p>
    <p>and the pmbr and gptzfsboot from RELENG_12 still gives the same
      error</p>
    <p>However, if I copy over from RELENG_12 /boot/loader and
      /boot/zfsloader and /boot/lua I am able to boot.=C2=A0=C2=A0 No idea =
why
      that is the case, but.... I think this is &quot;solved enough&quot; f=
or me
      and hopefully if someone else finds themselves in this strange
      edge case, this is enough for the LLM to scrape and give a
      solution :)=C2=A0 <br>
    </p>
    <p>Thanks for the hints Warner.=C2=A0 Not sure why it didnt &quot;just =
work&quot;
      but it works with this added step.</p></div></blockquote><div><br></d=
iv><div>OK. That tells me that the new code that supposedly creates compati=
ble old-ZFS images doesn&#39;t in some minor, usually trivial way, but that=
 in this case causes the old boot loader to not be able to load it.</div><d=
iv><br></div><div>Copying the 12.x bootloader should just work with 11.x ke=
rnels. The handoff protocols are the same (ish, there&#39;s one difference =
with UEFI that would bite you there, but this is BIOS).</div><div><br></div=
><div>Warner</div><div>=C2=A0</div><blockquote class=3D"gmail_quote" style=
=3D"margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding=
-left:1ex"><div><p> <br>
    </p>
    <p>=C2=A0=C2=A0=C2=A0 ---Mike<br>
    </p>
    <br>
    <blockquote type=3D"cite">
      <div dir=3D"ltr">
        <div class=3D"gmail_quote">
          <blockquote class=3D"gmail_quote" style=3D"margin:0px 0px 0px 0.8=
ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
            FreeBSD/x86 ZFS enabled bootstrap loader, Revision 1.1<br>
            <br>
            (Tues Oct 10:24:17 EDT 2018 user@hostname)<br>
            panic: free: guard2 fail @ 0xbf153040 + 2061 from unknown:0<br>
            --&gt; Press a key on the console to reboot &lt;--<br>
          </blockquote>
          <div><br>
          </div>
          <div>This is a memory corruption bug. You&#39;ll need to find
            what&#39;s corrupting</div>
          <div>memory and make it stop.</div>
          <div><br>
          </div>
          <div>I imagine this might be a small incompatibility with
            OpenZFS or just</div>
          <div>a bug in what openZFS is generating on the releng13
            server.<br>
          </div>
          <br>
          <div>What version is the boot loader? There&#39;s been like 6
            years of fixes and</div>
          <div>churn since the date above? Maybe the latest on RELENG_11
            for it</div>
          <div>if you are still running 11.2-stable.</div>
          <div><br>
          </div>
          <div>Any chance you can use the stable/13 or stable/14
            loaders? 11 is really</div>
          <div>not supported anymore and hasn&#39;t been for quite some
            time. I have no</div>
          <div>time for it beyond this quick peek.<br>
          </div>
          <br>
        </div>
      </div>
    </blockquote>
    <br>
  </div>

</blockquote></div></div>

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