+ kcov-dont-generate-a-warning-on-vm_insert_pages-failure.patch added to -mm tree

+ kcov-dont-generate-a-warning-on-vm_insert_pages-failure.patch added to -mm tree

[Andrew Morton]

The patch titled
     Subject: kcov: don't generate a warning on vm_insert_page()'s failure
has been added to the -mm tree.  Its filename is
     kcov-dont-generate-a-warning-on-vm_insert_pages-failure.patch

This patch should soon appear at
    https://ozlabs.org/~akpm/mmots/broken-out/kcov-dont-generate-a-warning-on-vm_insert_pages-failure.patch
and later at
    https://ozlabs.org/~akpm/mmotm/broken-out/kcov-dont-generate-a-warning-on-vm_insert_pages-failure.patch

Before you just go and hit "reply", please:
   a) Consider who else should be cc'ed
   b) Prefer to cc a suitable mailing list as well
   c) Ideally: find the original patch on the mailing list and do a
      reply-to-all to that, adding suitable additional cc's

*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***

The -mm tree is included into linux-next and is updated
there every 3-4 working days

------------------------------------------------------
From: Aleksandr Nogikh <nogikh@google.com>
Subject: kcov: don't generate a warning on vm_insert_page()'s failure

vm_insert_page()'s failure is not an unexpected condition, so don't do
WARN_ONCE() in such a case.

Instead, print a kernel message and just return an error code.

Link: https://lkml.kernel.org/r/20220401182512.249282-1-nogikh@google.com
Signed-off-by: Aleksandr Nogikh <nogikh@google.com>
Acked-by: Marco Elver <elver@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Taras Madan <tarasmadan@google.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---


--- a/kernel/kcov.c~kcov-dont-generate-a-warning-on-vm_insert_pages-failure
+++ a/kernel/kcov.c
@@ -475,8 +475,11 @@ static int kcov_mmap(struct file *filep,
 	vma->vm_flags |= VM_DONTEXPAND;
 	for (off = 0; off < size; off += PAGE_SIZE) {
 		page = vmalloc_to_page(kcov->area + off);
-		if (vm_insert_page(vma, vma->vm_start + off, page))
-			WARN_ONCE(1, "vm_insert_page() failed");
+		res = vm_insert_page(vma, vma->vm_start + off, page);
+		if (res) {
+			pr_warn_once("kcov: vm_insert_page() failed\n");
+			return res;
+		}
 	}
 	return 0;
 exit:
_

Patches currently in -mm which might be from nogikh@google.com are

kcov-dont-generate-a-warning-on-vm_insert_pages-failure.patch