+ mm-kmemleak-move-set_track_prepare-outside-raw_spinlocks.patch added to mm-hotfixes-unstable branch

+ mm-kmemleak-move-set_track_prepare-outside-raw_spinlocks.patch added to mm-hotfixes-unstable branch

[Andrew Morton]

The patch titled
     Subject: mm/kmemleak: move set_track_prepare() outside raw_spinlocks
has been added to the -mm mm-hotfixes-unstable branch.  Its filename is
     mm-kmemleak-move-set_track_prepare-outside-raw_spinlocks.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-kmemleak-move-set_track_prepare-outside-raw_spinlocks.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: Liu Shixin <liushixin2@huawei.com>
Subject: mm/kmemleak: move set_track_prepare() outside raw_spinlocks
Date: Wed, 15 Nov 2023 16:21:38 +0800

set_track_prepare() will call __alloc_pages() which attempts to acquire
zone->lock(spinlocks), so move it outside object->lock(raw_spinlocks)
because it's not right to acquire spinlocks while holding raw_spinlocks in
RT mode.

Link: https://lkml.kernel.org/r/20231115082138.2649870-3-liushixin2@huawei.com
Signed-off-by: Liu Shixin <liushixin2@huawei.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Patrick Wang <patrick.wang.shcn@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/kmemleak.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

--- a/mm/kmemleak.c~mm-kmemleak-move-set_track_prepare-outside-raw_spinlocks
+++ a/mm/kmemleak.c
@@ -1152,6 +1152,7 @@ EXPORT_SYMBOL_GPL(kmemleak_free_percpu);
 void __ref kmemleak_update_trace(const void *ptr)
 {
 	struct kmemleak_object *object;
+	depot_stack_handle_t trace_handle;
 	unsigned long flags;
 
 	pr_debug("%s(0x%px)\n", __func__, ptr);
@@ -1168,8 +1169,9 @@ void __ref kmemleak_update_trace(const v
 		return;
 	}
 
+	trace_handle = set_track_prepare();
 	raw_spin_lock_irqsave(&object->lock, flags);
-	object->trace_handle = set_track_prepare();
+	object->trace_handle = trace_handle;
 	raw_spin_unlock_irqrestore(&object->lock, flags);
 
 	put_object(object);
_

Patches currently in -mm which might be from liushixin2@huawei.com are

revert-mm-kmemleak-move-the-initialisation-of-object-to-__link_object.patch
mm-kmemleak-move-set_track_prepare-outside-raw_spinlocks.patch
mm-vmscan-try-to-reclaim-swapcache-pages-if-no-swap-space.patch
mm-vmscan-try-to-reclaim-swapcache-pages-if-no-swap-space-v6.patch