+ perf-core-fix-max_order-usage-in-rb_alloc_aux_page.patch added to mm-unstable branch

[Andrew Morton <akpm@linux-foundation.org>]

The patch titled
     Subject: perf/core: fix MAX_ORDER usage in rb_alloc_aux_page()
has been added to the -mm mm-unstable branch.  Its filename is
     perf-core-fix-max_order-usage-in-rb_alloc_aux_page.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/perf-core-fix-max_order-usage-in-rb_alloc_aux_page.patch

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

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------------------------------------------------------
From: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Subject: perf/core: fix MAX_ORDER usage in rb_alloc_aux_page()
Date: Wed, 15 Mar 2023 14:31:29 +0300

MAX_ORDER is not inclusive: the maximum allocation order buddy allocator
can deliver is MAX_ORDER-1.

Fix MAX_ORDER usage in rb_alloc_aux_page().

Link: https://lkml.kernel.org/r/20230315113133.11326-7-kirill.shutemov@linux.intel.com
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 kernel/events/ring_buffer.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/kernel/events/ring_buffer.c~perf-core-fix-max_order-usage-in-rb_alloc_aux_page
+++ a/kernel/events/ring_buffer.c
@@ -609,8 +609,8 @@ static struct page *rb_alloc_aux_page(in
 {
 	struct page *page;
 
-	if (order > MAX_ORDER)
-		order = MAX_ORDER;
+	if (order >= MAX_ORDER)
+		order = MAX_ORDER - 1;
 
 	do {
 		page = alloc_pages_node(node, PERF_AUX_GFP, order);
_

Patches currently in -mm which might be from kirill.shutemov@linux.intel.com are

sparc-mm-fix-max_order-usage-in-tsb_grow.patch
um-fix-max_order-usage-in-linux_main.patch
floppy-fix-max_order-usage.patch
drm-i915-fix-max_order-usage-in-i915_gem_object_get_pages_internal.patch
genwqe-fix-max_order-usage.patch
perf-core-fix-max_order-usage-in-rb_alloc_aux_page.patch
mm-page_reporting-fix-max_order-usage-in-page_reporting_register.patch
mm-slub-fix-max_order-usage-in-calculate_order.patch
iommu-fix-max_order-usage-in-__iommu_dma_alloc_pages.patch
mm-treewide-redefine-max_order-sanely.patch