diff --git a/cabal-install/src/Distribution/Client/Dependency.hs b/cabal-install/src/Distribution/Client/Dependency.hs
index 5bc5ec51b86..056d0ffed05 100644
--- a/cabal-install/src/Distribution/Client/Dependency.hs
+++ b/cabal-install/src/Distribution/Client/Dependency.hs
@@ -456,19 +456,34 @@ dontUpgradeNonUpgradeablePackages params =
         . InstalledPackageIndex.lookupPackageName
           (depResolverInstalledPkgIndex params)
 
--- NOTE: the lists of non-upgradable and non-installable packages used to be
+-- | The set of non-reinstallable packages includes those which cannot be
+-- rebuilt using a GHC installation and Hackage-published source distribution.
+-- There are a few reasons why this might be true:
+--
+--  * the package overrides its unit ID (e.g. with ghc's @-this-unit-id@ flag),
+--    which can result in multiple indistinguishable packages (having potentially
+--    different ABIs) with the same unit ID.
+--
+--  * the package contains definitions of wired-in declarations which tie
+--    it to a particular compiler (e.g. we can't build link against
+--    @base-4.18.0.0@ using GHC 9.6.1).
+--
+--  * the package does not have a complete (that is, buildable) source distribution.
+--    For instance, some packages provided by GHC rely on files outside of the
+--    source tree generated by GHC's build system.
+--
+-- Note: the list of non-upgradable/non-installable packages used to be
 -- respectively in this module and in `Distribution.Solver.Modular.Solver`.
 -- Since they were kept synced, they are now combined in the following list.
 --
--- See: https://github.com/haskell/cabal/issues/8581
+-- See: https://github.com/haskell/cabal/issues/8581 and
+-- https://github.com/haskell/cabal/issues/9064.
 nonUpgradeablePackages :: [PackageName]
 nonUpgradeablePackages =
   [ mkPackageName "base"
   , mkPackageName "ghc-bignum"
   , mkPackageName "ghc-prim"
-  , mkPackageName "ghc-boot"
   , mkPackageName "ghc"
-  , mkPackageName "ghci"
   , mkPackageName "integer-gmp"
   , mkPackageName "integer-simple"
   , mkPackageName "template-haskell"
diff --git a/cabal-install/tests/UnitTests/Distribution/Solver/Modular/Solver.hs b/cabal-install/tests/UnitTests/Distribution/Solver/Modular/Solver.hs
index dedb20bc70c..d5973598fa9 100644
--- a/cabal-install/tests/UnitTests/Distribution/Solver/Modular/Solver.hs
+++ b/cabal-install/tests/UnitTests/Distribution/Solver/Modular/Solver.hs
@@ -203,12 +203,6 @@ tests =
       , runTest $
           mkTest dbNonupgrade "Refuse to install newer ghc requested by another library" ["A"] $
             solverFailure (isInfixOf "rejecting: ghc-2.0.0 (constraint from non-upgradeable package requires installed instance)")
-      , runTest $
-          mkTest dbNonupgrade "Refuse to install newer ghci requested by another library" ["B"] $
-            solverFailure (isInfixOf "rejecting: ghci-2.0.0 (constraint from non-upgradeable package requires installed instance)")
-      , runTest $
-          mkTest dbNonupgrade "Refuse to install newer ghc-boot requested by another library" ["C"] $
-            solverFailure (isInfixOf "rejecting: ghc-boot-2.0.0 (constraint from non-upgradeable package requires installed instance)")
       ]
   , testGroup
       "reject-unconstrained"
@@ -1301,8 +1295,6 @@ dbBase =
 dbNonupgrade :: ExampleDb
 dbNonupgrade =
   [ Left $ exInst "ghc" 1 "ghc-1" []
-  , Left $ exInst "ghci" 1 "ghci-1" []
-  , Left $ exInst "ghc-boot" 1 "ghc-boot-1" []
   , Right $ exAv "ghc" 2 []
   , Right $ exAv "ghci" 2 []
   , Right $ exAv "ghc-boot" 2 []