Wrong -dirty suffix set by setlocalversion (was: BUG in git diff-index)

Commit Message

Mason, Michael W May 24, 2018, 11:03 p.m. UTC

How about something like this? It ignores attributes that should have no
bearing on whether the kernel is considered dirty. Copied trees with no other
changes would no longer be marked with -dirty. Plus it works on read-only
media since no index updating is required.

Would this also be considered kosher, at least for the purposes of
setlocalversion?

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Comments

Marc Herbert May 25, 2018, 3:50 a.m. UTC | #1

On 24/05/2018 16:03, Mike Mason wrote:

> diff --git a/scripts/setlocalversion b/scripts/setlocalversion
> index 71f39410691b..9da4c5e83285 100755
> --- a/scripts/setlocalversion
> +++ b/scripts/setlocalversion
> @@ -73,8 +73,10 @@ scm_version()
>  			printf -- '-svn%s' "`git svn find-rev $head`"
>  		fi
>  
> -		# Check for uncommitted changes
> -		if git diff-index --name-only HEAD | grep -qv "^scripts/package"; then
> +		# Check for uncommitted changes. Only check mtime and size.
> +       # Ignore insequential ctime, uid, gid and inode differences.
> +		if git -c "core.checkstat=minimal" diff-index --name-only HEAD | \
> +				grep -qv "^scripts/package"; then
>  			printf '%s' -dirty
>  		fi

FWIW:

Reported-by: [e-mail]
Reviewed-by: [e-mail]  (assuming a future and decent commit message)
Tested-by: [e-mail]


So the real use case is making a copy of a whole tree before building.
Typical in automated builds, old example:
https://groups.google.com/a/chromium.org/d/msg/chromium-os-dev/zxOa0OLWFkw/N_Sb7EZOBwAJ 

Here's a more complex but faster and more transparent way to test Mike's fix
than copying an entire tree:

# Make sure you start from a clean state
git describe --dirty      # must not -dirty

make prepare

# Simulate a copy of the tree but with just one file
rsync --perms --times  README   README.mtime_backup
rm  README
rsync --perms --times  README.mtime_backup   README
stat  README  README.mtime_backup 

# Demo the BUG fixed by Mike
./scripts/setlocalversion # -dirty BUG! because spurious inode ctime difference
git diff-index  HEAD
git describe --dirty      # not -dirty
./scripts/setlocalversion # not -dirty any more cause describe refreshed index

# Make sure mtime still causes -dirty with AND without Mike's fix
touch README
./scripts/setlocalversion # -dirty
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Patch

diff --git a/scripts/setlocalversion b/scripts/setlocalversion
index 71f39410691b..9da4c5e83285 100755
--- a/scripts/setlocalversion
+++ b/scripts/setlocalversion
@@ -73,8 +73,10 @@  scm_version()
 			printf -- '-svn%s' "`git svn find-rev $head`"
 		fi
 
-		# Check for uncommitted changes
-		if git diff-index --name-only HEAD | grep -qv "^scripts/package"; then
+		# Check for uncommitted changes. Only check mtime and size.
+       # Ignore insequential ctime, uid, gid and inode differences.
+		if git -c "core.checkstat=minimal" diff-index --name-only HEAD | \
+				grep -qv "^scripts/package"; then
 			printf '%s' -dirty
 		fi