+ kasan-speed-up-match_all_mem_tag-test-for-sw_tags.patch added to mm-unstable branch

+ kasan-speed-up-match_all_mem_tag-test-for-sw_tags.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: kasan: speed up match_all_mem_tag test for SW_TAGS
has been added to the -mm mm-unstable branch.  Its filename is
     kasan-speed-up-match_all_mem_tag-test-for-sw_tags.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/kasan-speed-up-match_all_mem_tag-test-for-sw_tags.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: Andrey Konovalov <andreyknvl@google.com>
Subject: kasan: speed up match_all_mem_tag test for SW_TAGS
Date: Thu, 21 Dec 2023 21:04:53 +0100

Checking all 256 possible tag values in the match_all_mem_tag KASAN test
is slow and produces 256 reports.  Instead, just check the first 8 and the
last 8.

Link: https://lkml.kernel.org/r/6fe51262defd80cdc1150c42404977aafd1b6167.1703188911.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Marco Elver <elver@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/kasan/kasan_test.c |    8 ++++++++
 1 file changed, 8 insertions(+)

--- a/mm/kasan/kasan_test.c~kasan-speed-up-match_all_mem_tag-test-for-sw_tags
+++ a/mm/kasan/kasan_test.c
@@ -1797,6 +1797,14 @@ static void match_all_mem_tag(struct kun
 
 	/* For each possible tag value not matching the pointer tag. */
 	for (tag = KASAN_TAG_MIN; tag <= KASAN_TAG_KERNEL; tag++) {
+		/*
+		 * For Software Tag-Based KASAN, skip the majority of tag
+		 * values to avoid the test printing too many reports.
+		 */
+		if (IS_ENABLED(CONFIG_KASAN_SW_TAGS) &&
+		    tag >= KASAN_TAG_MIN + 8 && tag <= KASAN_TAG_KERNEL - 8)
+			continue;
+
 		if (tag == get_tag(ptr))
 			continue;
 
_

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

kasan-rename-kasan_slab_free_mempool-to-kasan_mempool_poison_object.patch
kasan-move-kasan_mempool_poison_object.patch
kasan-document-kasan_mempool_poison_object.patch
kasan-add-return-value-for-kasan_mempool_poison_object.patch
kasan-introduce-kasan_mempool_unpoison_object.patch
kasan-introduce-kasan_mempool_poison_pages.patch
kasan-introduce-kasan_mempool_unpoison_pages.patch
kasan-clean-up-__kasan_mempool_poison_object.patch
kasan-save-free-stack-traces-for-slab-mempools.patch
kasan-clean-up-and-rename-____kasan_kmalloc.patch
kasan-introduce-poison_kmalloc_large_redzone.patch
kasan-save-alloc-stack-traces-for-mempool.patch
mempool-skip-slub_debug-poisoning-when-kasan-is-enabled.patch
mempool-use-new-mempool-kasan-hooks.patch
mempool-introduce-mempool_use_prealloc_only.patch
kasan-add-mempool-tests.patch
kasan-rename-pagealloc-tests.patch
kasan-reorder-tests.patch
kasan-rename-and-document-kasan_unpoison_object_data.patch
skbuff-use-mempool-kasan-hooks.patch
io_uring-use-mempool-kasan-hook.patch
lib-stackdepot-add-printk_deferred_enter-exit-guards.patch
kasan-handle-concurrent-kasan_record_aux_stack-calls.patch
kasan-memset-free-track-in-qlink_free.patch
lib-stackdepot-fix-comment-in-include-linux-stackdepoth.patch
kasan-arm64-improve-comments-for-kasan_shadow_start-end.patch
mm-kasan-use-kasan_tag_kernel-instead-of-0xff.patch
kasan-improve-kasan_non_canonical_hook.patch
kasan-clean-up-kasan_requires_meta.patch
kasan-update-kasan_poison-documentation-comment.patch
kasan-clean-up-is_kfence_address-checks.patch
kasan-respect-config_kasan_vmalloc-for-kasan_flag_vmalloc.patch
kasan-check-kasan_vmalloc_enabled-in-vmalloc-tests.patch
kasan-export-kasan_poison-as-gpl.patch
kasan-remove-slub-checks-for-page_alloc-fallbacks-in-tests.patch
kasan-speed-up-match_all_mem_tag-test-for-sw_tags.patch