[yocto] Details on Bug #963 kernel tarball corruption.

[Richard Purdie]

On Thu, 2011-07-07 at 13:34 -0700, Flanagan, Elizabeth wrote:
> I wanted to ping the list on this bug as I've drilled down into it and
> I see what's going on. These are the steps to reproduce it and I have
> some questions at the end....
> 
> The issue: The autobuilder has been serving up bad kernel source
> tarballs. This is not an autobuilder issue. I've narrowed this down to
> being an issue with do_fetch and do_unpack....
> 
> First, I created a local linux-yocto repo and modified
> meta/recipes-kernel/linux/linux-yocto_2.6.37.bb to point to it:
> 
> SRCREV_machine = ${AUTOREV}
> SRCREV_meta = ${AUTOREV}
> 
> SRC_URI = "git:///srv/build/build/repo/git.pokylinux.org.linux-yocto-2.6.37;protocol=file;nocheckout=1;branch=${KBRANCH},meta;name=machine,meta"
> 
> I do bitbake virtual/kernel -c kernel_checkout -f and the repo is
> fetched into my DL_DIR, unpacked into
> tmp/work/qemux86-poky-linux/linux-yocto-2.6.37....r20/git and then
> do_kernel_checkout runs. At this point, everything is correct.
> 
> At this point my local SRC_URI repo is:
> 
> * master
>   meta
>   yocto/base
>   yocto/eg20t
>   yocto/emgd
>   yocto/gma500
> ....
> 
> My clone in DL_DIR is the same.
> 
> My clone in  tmp/work/qemux86-poky-linux/linux-yocto-2.6.37....r20/linux
> looks like this:
> 
>   master
>   meta
>   yocto/base
>   yocto/eg20t
>   yocto/emgd
>   yocto/gma500
>   ....
>   remotes/origin/master
>   remotes/origin/meta
>   remotes/origin/yocto/base
>   remotes/origin/yocto/eg20t
>   remotes/origin/yocto/emgd
>   remotes/origin/yocto/gma500
> 
> With the local head branches and the remotes being the same.
> 
> Now, on to where this gets ugly.
> 
> I commit a new branch to my SRC_URI repo:
> 
> My SRC_URI:
> 
> BAD_BRANCH
> master
> meta
> yocto/base
> yocto/eg20t
> yocto/emgd
> yocto/gma500
> ....
> 
> I re-run fetch and my DL_DIR looks like this:
> 
> * master
>   meta
>   yocto/base
>   yocto/eg20t
>   yocto/emgd
>   yocto/gma500
> ....
>   remotes/origin/BAD_BRANCH
>   remotes/origin/master
>   remotes/origin/meta
>   remotes/origin/yocto/base
>   remotes/origin/yocto/eg20t
>   remotes/origin/yocto/emgd
>   remotes/origin/yocto/gma500
> 
> Notice, the new BAD_BRANCH is now only in remotes. This *should* be
> ok, since after we do_unpack we run do_kernel_checkout which should
> copy the refs in remotes to heads

I think we hit game over at this point. BAD_BRANCH should be present and
isn't :(.

I talked quickly with Beth over jabber. I think this is a fetcher bug
and something like:

diff --git a/bitbake/lib/bb/fetch2/git.py b/bitbake/lib/bb/fetch2/git.py
index f3bc793..7954f66 100644
--- a/bitbake/lib/bb/fetch2/git.py
+++ b/bitbake/lib/bb/fetch2/git.py
@@ -170,7 +170,7 @@ class Git(FetchMethod):
 
         # If the repo still doesn't exist, fallback to cloning it
         if not os.path.exists(ud.clonedir):
-            clone_cmd = "%s clone --bare %s://%s%s%s %s" % \
+            clone_cmd = "%s clone --bare --mirror %s://%s%s%s %s" % \
                   (ud.basecmd, ud.proto, username, ud.host, ud.path, ud.clonedir)
             bb.fetch2.check_network_access(d, clone_cmd)
             runfetchcmd(clone_cmd, d)
@@ -188,7 +188,7 @@ class Git(FetchMethod):
             except bb.fetch2.FetchError:
                 logger.debug(1, "No Origin")
             
-            runfetchcmd("%s remote add origin %s://%s%s%s" % (ud.basecmd, ud.proto, username, ud.host, ud.path), d)
+            runfetchcmd("%s remote add --mirror origin %s://%s%s%s" % (ud.basecmd, ud.proto, username, ud.host, ud.path), d)
             fetch_cmd = "%s fetch --all -t" % ud.basecmd
             bb.fetch2.check_network_access(d, fetch_cmd, ud.url)
             runfetchcmd(fetch_cmd, d)

might just fix this (since it means a refspec is added to keep the
remote and local heads in sync).

Cheers,

Richard