FAILED: patch "[PATCH] mm/vmalloc: leave lazy MMU mode on PTE mapping error" failed to apply to 6.1-stable tree

[<gregkh@linuxfoundation.org>]

The patch below does not apply to the 6.1-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.1.y
git checkout FETCH_HEAD
git cherry-pick -x fea18c686320a53fce7ad62a87a3e1d10ad02f31
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2025071315-rural-exploring-3260@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^..

Possible dependencies:



thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From fea18c686320a53fce7ad62a87a3e1d10ad02f31 Mon Sep 17 00:00:00 2001
From: Alexander Gordeev <agordeev@linux.ibm.com>
Date: Mon, 23 Jun 2025 09:57:21 +0200
Subject: [PATCH] mm/vmalloc: leave lazy MMU mode on PTE mapping error

vmap_pages_pte_range() enters the lazy MMU mode, but fails to leave it in
case an error is encountered.

Link: https://lkml.kernel.org/r/20250623075721.2817094-1-agordeev@linux.ibm.com
Fixes: 2ba3e6947aed ("mm/vmalloc: track which page-table levels were modified")
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Closes: https://lore.kernel.org/r/202506132017.T1l1l6ME-lkp@intel.com/
Reviewed-by: Ryan Roberts <ryan.roberts@arm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index ab986dd09b6a..6dbcdceecae1 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -514,6 +514,7 @@ static int vmap_pages_pte_range(pmd_t *pmd, unsigned long addr,
 		unsigned long end, pgprot_t prot, struct page **pages, int *nr,
 		pgtbl_mod_mask *mask)
 {
+	int err = 0;
 	pte_t *pte;
 
 	/*
@@ -530,12 +531,18 @@ static int vmap_pages_pte_range(pmd_t *pmd, unsigned long addr,
 	do {
 		struct page *page = pages[*nr];
 
-		if (WARN_ON(!pte_none(ptep_get(pte))))
-			return -EBUSY;
-		if (WARN_ON(!page))
-			return -ENOMEM;
-		if (WARN_ON(!pfn_valid(page_to_pfn(page))))
-			return -EINVAL;
+		if (WARN_ON(!pte_none(ptep_get(pte)))) {
+			err = -EBUSY;
+			break;
+		}
+		if (WARN_ON(!page)) {
+			err = -ENOMEM;
+			break;
+		}
+		if (WARN_ON(!pfn_valid(page_to_pfn(page)))) {
+			err = -EINVAL;
+			break;
+		}
 
 		set_pte_at(&init_mm, addr, pte, mk_pte(page, prot));
 		(*nr)++;
@@ -543,7 +550,8 @@ static int vmap_pages_pte_range(pmd_t *pmd, unsigned long addr,
 
 	arch_leave_lazy_mmu_mode();
 	*mask |= PGTBL_PTE_MODIFIED;
-	return 0;
+
+	return err;
 }
 
 static int vmap_pages_pmd_range(pud_t *pud, unsigned long addr,