+ virtio_balloon-set-pr_devorder-to-new-default.patch added to mm-new branch

+ virtio_balloon-set-pr_devorder-to-new-default.patch added to mm-new branch

[Andrew Morton]

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The patch titled
     Subject: virtio_balloon: set pr_dev.order to new default
has been added to the -mm mm-new branch.  Its filename is
     virtio_balloon-set-pr_devorder-to-new-default.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/virtio_balloon-set-pr_devorder-to-new-default.patch

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

Note, mm-new is a provisional staging ground for work-in-progress
patches, and acceptance into mm-new is a notification for others take
notice and to finish up reviews.  Please do not hesitate to respond to
review feedback and post updated versions to replace or incrementally
fixup patches in mm-new.

The mm-new branch of mm.git is not included in linux-next

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------------------------------------------------------
From: Yuvraj Sakshith <yuvraj.sakshith@oss.qualcomm.com>
Subject: virtio_balloon: set pr_dev.order to new default
Date: Wed, 25 Feb 2026 23:01:25 -0800

Drivers registering with page reporting used zero as a way to signal
page_reporting_order to be set as a default value (either passed as a
param or MAX_PAGE_ORDER).

Since page_reporting_order can now have zero as valid order, default
fallback value send by drivers to page reporting is now -1.

Link: https://lkml.kernel.org/r/20260226070125.3732265-4-yuvraj.sakshith@oss.qualcomm.com
Signed-off-by: Yuvraj Sakshith <yuvraj.sakshith@oss.qualcomm.com>
Cc: Brendan Jackman <jackmanb@google.com>
Cc: David Hildenbrand <david@kernel.org>
Cc: Dexuan Cui <decui@microsoft.com>
Cc: Eugenio Pérez <eperezma@redhat.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: K. Y. Srinivasan <kys@microsoft.com>
Cc: Long Li <longli@microsoft.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Wei Liu <wei.liu@kernel.org>
Cc: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 drivers/virtio/virtio_balloon.c |   14 ++++++++++++++
 1 file changed, 14 insertions(+)

--- a/drivers/virtio/virtio_balloon.c~virtio_balloon-set-pr_devorder-to-new-default
+++ a/drivers/virtio/virtio_balloon.c
@@ -1023,6 +1023,20 @@ static int virtballoon_probe(struct virt
 		}
 
 		/*
+		 * page_reporting_register() takes the order either
+		 * from the driver or the commandline. If neither
+		 * are provided, it falls back to MAX_PAGE_ORDER.
+		 *
+		 * Order given by the driver is required to be in the
+		 * range [0, MAX_PAGE_ORDER].
+		 *
+		 * One way for the driver to not provide any order
+		 * is by setting it to -1.
+		 */
+
+		vb->pr_dev_info.order = -1;
+
+		/*
 		 * The default page reporting order is @pageblock_order, which
 		 * corresponds to 512MB in size on ARM64 when 64KB base page
 		 * size is used. The page reporting won't be triggered if the
_

Patches currently in -mm which might be from yuvraj.sakshith@oss.qualcomm.com are

mm-page_reporting-allow-zero-page_reporting_order.patch
hv_balloon-change-default-page-reporting-order.patch
virtio_balloon-set-pr_devorder-to-new-default.patch