+ alloc_tag-avoid-implicit-padding-in-uapi.patch added to mm-hotfixes-unstable branch

+ alloc_tag-avoid-implicit-padding-in-uapi.patch added to mm-hotfixes-unstable branch

[Andrew Morton]

The patch titled
     Subject: alloc_tag: avoid implicit padding in uapi
has been added to the -mm mm-hotfixes-unstable branch.  Its filename is
     alloc_tag-avoid-implicit-padding-in-uapi.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/alloc_tag-avoid-implicit-padding-in-uapi.patch

This patch will later appear in the mm-hotfixes-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Arnd Bergmann <arnd@arndb.de>
Subject: alloc_tag: avoid implicit padding in uapi
Date: Tue, 15 Sep 2026 22:23:47 +0200

The impliied padding causes a harmless warning when testing the uapi
headers with -Wpadded that could in theory indicate incompatibilies or
data leaks:

./usr/include/linux/alloc_tag.h:41:1: error: padding struct size to alignment boundary with 7 bytes [-Werror=padded]

The code here is fine, but it's better to make the padding explicit and
avoid the warning here.

Link: https://lore.kernel.org/20260915202404.3568029-1-arnd@kernel.org
Fixes: 1d581ab2348c ("alloc_tag: add ioctl to /proc/allocinfo")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Hao Ge <hao.ge@linux.dev>
Cc: Suren Baghdasaryan <surenb@google.com>
---

 include/uapi/linux/alloc_tag.h |    1 +
 1 file changed, 1 insertion(+)

--- a/include/uapi/linux/alloc_tag.h~alloc_tag-avoid-implicit-padding-in-uapi
+++ a/include/uapi/linux/alloc_tag.h
@@ -38,6 +38,7 @@ struct allocinfo_counter {
 	__u64 bytes;
 	__u64 calls;
 	__u8 accurate;
+	__u8 pad[7];
 } __attribute__((aligned(8)));
 
 struct allocinfo_tag_data {
_

Patches currently in -mm which might be from arnd@arndb.de are

alloc_tag-avoid-implicit-padding-in-uapi.patch