diff --git a/CHANGELOG b/CHANGELOG
index de7bca3074..bf4b7fe36d 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -3,6 +3,7 @@ git-annex (10.20231130) UNRELEASED; urgency=medium
   * Make git-annex get/copy/move --from foo override configuration of 
     remote.foo.annex-ignore, as documented.
   * Support git-annex copy/move --from-anywhere --to remote.
+  * sync: Fix locking problems during merge when annex.pidlock is set.
 
  -- Joey Hess <id@joeyh.name>  Thu, 30 Nov 2023 14:48:12 -0400
 
diff --git a/Command/Sync.hs b/Command/Sync.hs
index 851776f95f..3a3d039a89 100644
--- a/Command/Sync.hs
+++ b/Command/Sync.hs
@@ -76,6 +76,7 @@ import Annex.TaggedPush
 import Annex.CurrentBranch
 import Annex.Import
 import Annex.CheckIgnore
+import Annex.PidLock
 import Types.FileMatcher
 import Types.GitConfig
 import Types.Availability
@@ -352,15 +353,16 @@ mergeConfig mergeunrelated = do
 		]
 
 merge :: CurrBranch -> [Git.Merge.MergeConfig] -> SyncOptions -> Git.Branch.CommitMode -> [Git.Branch] -> Annex Bool
-merge currbranch mergeconfig o commitmode tomergel = do
-	canresolvemerge <- if resolveMergeOverride o
-		then getGitConfigVal annexResolveMerge
-		else return False
-	and <$> case currbranch of
-		(Just b, Just adj) -> forM tomergel $ \tomerge ->
-			mergeToAdjustedBranch tomerge (b, adj) mergeconfig canresolvemerge commitmode
-		(b, _) -> forM tomergel $ \tomerge ->
-			autoMergeFrom tomerge b mergeconfig commitmode canresolvemerge
+merge currbranch mergeconfig o commitmode tomergel = 
+	runsGitAnnexChildProcessViaGit $ do
+		canresolvemerge <- if resolveMergeOverride o
+			then getGitConfigVal annexResolveMerge
+			else return False
+		and <$> case currbranch of
+			(Just b, Just adj) -> forM tomergel $ \tomerge ->
+				mergeToAdjustedBranch tomerge (b, adj) mergeconfig canresolvemerge commitmode
+			(b, _) -> forM tomergel $ \tomerge ->
+				autoMergeFrom tomerge b mergeconfig commitmode canresolvemerge
 
 syncBranch :: Git.Branch -> Git.Branch
 syncBranch = Git.Ref.underBase "refs/heads/synced" . origBranch
diff --git a/doc/bugs/Race_condition_or_double-locking_with_pidlock.mdwn b/doc/bugs/Race_condition_or_double-locking_with_pidlock.mdwn
index db93536ffb..4347fc2e06 100644
--- a/doc/bugs/Race_condition_or_double-locking_with_pidlock.mdwn
+++ b/doc/bugs/Race_condition_or_double-locking_with_pidlock.mdwn
@@ -55,3 +55,5 @@ Could this be caused by e.g. git annex running git merge which runs git annex fi
 ### Have you had any luck using git-annex before? (Sometimes we get tired of reading bug reports all day and a lil' positive end note does wonders)
 
 Lots! This problem popped up during our regular use of git-annex in plant genomic research, where we use git annex to manage and move our analyses between the many clusters we must use for computation. Git annex is indispensable for this use case!!
+
+> [[fixed|done]] (for the merge case at least) --[[Joey]]
diff --git a/doc/bugs/Race_condition_or_double-locking_with_pidlock/comment_1_bd92615c640ff017cd8a2ebfcc117a37._comment b/doc/bugs/Race_condition_or_double-locking_with_pidlock/comment_1_bd92615c640ff017cd8a2ebfcc117a37._comment
new file mode 100644
index 0000000000..daa07df33f
--- /dev/null
+++ b/doc/bugs/Race_condition_or_double-locking_with_pidlock/comment_1_bd92615c640ff017cd8a2ebfcc117a37._comment
@@ -0,0 +1,27 @@
+[[!comment format=mdwn
+ username="joey"
+ subject="""comment 1"""
+ date="2023-12-04T17:06:11Z"
+ content="""
+> Could this be caused by e.g. git annex running git merge which runs git annex
+> filterprocess (directly or via git status), and git-annex-filterprocess tries
+> to take the pidlock that git-annex-sync already has?
+
+If so you should be able to see the two git-annex's running in ps when this hang occurs
+with the git process in between them.
+That would be very helpful to verify since it would narrow down the git command
+that runs this git-annex child process.
+
+git-annex does deal with exactly this kind of scenario when running eg
+`git update-index`, by setting an environment variable to tell the child git-annex
+process not to re-lock the pid lock. But not in eg the case of a git merge.
+
+So, if you can narrow it down specifically to `git merge` running when this
+happens, or whatever other command, it should be easy to fix it.
+
+Hmm, I suppose that it makes sense `git merge` will sometimes need to check if
+a worktree file is modified, and so run git-annex. I'm pretty convinced by your
+transcript that it is the git merge that's hanging. So I've gone ahead and put
+in the workaround for that. There's of course still the possibility there's
+some other git command I've not anticipated that still needs the workaround.
+"""]]