From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id ECB7920D4FF for ; Fri, 4 Sep 2026 00:20:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788481226; cv=none; b=tqMHRwX3Xd3lOtr/bi1tYRm/lA1JTtFD6frVY8ig2JNlNt13HE8YX+kx2BGDMflm1zc1D+HD1wv1/n/3AeOSlnhQooYmbFM52RfcEw1N69NBsYBOCVfg42MtxbbZpnDTGk9ttapNQWGACP7jtaxStU8hSO1x1EotpN2+aHbdxxQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788481226; c=relaxed/simple; bh=F2NcxLV5YKTa4vT6Hhlh1+LrdjoDd0snjYkAa4gEvUA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=XpcZmJqN6ESDFQP5dLu+N2M7aBUSSxaHT1tjYLFNzGQVleV0w0+9mEYpRo61Q9a9Ep/kjrthVzgYmN85M3Qvbp/+tVK656HbiMGli8y5mnMiQencIEL4pK/009jz88KlaqC/tw6zTEbWtYSpkbvw+i/3CYC+tMxjNwbZFD5l6rE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=S2scyPZS; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="S2scyPZS" Received: by smtp.kernel.org (Postfix) with ESMTPSA id ECF4F1F000E9; Fri, 4 Sep 2026 00:20:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1788481224; bh=01U0dP+UODhQiAjPhmcHPSxkSif5JbhijMhYlAxdTGg=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=S2scyPZSotnAVOAbd/9W34THitr6tCH0D+FzBnM52s84Iqpsjk3OmwQjWOWCix3jE 7D3Xqnyk+TeqhcnWzd2LDr9fNvY3IVGFowga2Czm+uQmzIlS/EHzigWYc9gloBBCga zwRujQdquRGbJwMWkBJTuSj1HIQ3Htk46B+1kQIPGRIEgCT0VOlNH191zRbQCh6YiK q8c+zcGgoNyjf2hKxTrhwYlzKeaawlk77eKR+El+LulmO2hQwODvet7g8eF0EAx04N 5ifInfTQ3UrXrGoXeR55Rzyb9V+7mA/T1J8M5teHK1d4hyviMIcIjkrkQdZZyduf/+ wXUKzv2CFMKUw== From: Sasha Levin To: stable@vger.kernel.org Cc: Vlastimil Babka , Harry Yoo , Suren Baghdasaryan , "Liam R. Howlett" , Sasha Levin Subject: [PATCH 6.18.y 1/2] mm/slab: move and refactor __kmem_cache_alias() Date: Thu, 3 Sep 2026 20:20:21 -0400 Message-ID: <20260904002022.2105689-1-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <2026090309-defame-darkening-edde@gregkh> References: <2026090309-defame-darkening-edde@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Vlastimil Babka [ Upstream commit 8598351edc42f38d2a1eaed9abca39c98e7b0bbf ] Move __kmem_cache_alias() to slab_common.c since it's called by __kmem_cache_create_args() and calls find_mergeable() that both are in this file. We can remove two slab.h declarations and make them static. Instead declare sysfs_slab_alias() from slub.c so that __kmem_cache_alias() can keep calling it. Add args parameter to __kmem_cache_alias() and find_mergeable() instead of align and ctor. With that we can also move the checks for usersize and sheaf_capacity there from __kmem_cache_create_args() and make the result more symmetric with slab_unmergeable(). No functional changes intended. Reviewed-by: Harry Yoo Reviewed-by: Suren Baghdasaryan Reviewed-by: Liam R. Howlett Signed-off-by: Vlastimil Babka Stable-dep-of: 7e98f8563956 ("mm/slub: fix missing debugfs entries for caches created before sysfs init") Signed-off-by: Sasha Levin --- mm/slab.h | 8 +++----- mm/slab_common.c | 44 +++++++++++++++++++++++++++++++++++++------- mm/slub.c | 30 +----------------------------- 3 files changed, 41 insertions(+), 41 deletions(-) diff --git a/mm/slab.h b/mm/slab.h index c452f2a32c801..0b49960bf07c9 100644 --- a/mm/slab.h +++ b/mm/slab.h @@ -299,9 +299,12 @@ struct kmem_cache { #define SLAB_SUPPORTS_SYSFS 1 void sysfs_slab_unlink(struct kmem_cache *s); void sysfs_slab_release(struct kmem_cache *s); +int sysfs_slab_alias(struct kmem_cache *s, const char *name); #else static inline void sysfs_slab_unlink(struct kmem_cache *s) { } static inline void sysfs_slab_release(struct kmem_cache *s) { } +static inline int sysfs_slab_alias(struct kmem_cache *s, const char *name) + { return 0; } #endif void *fixup_red_left(struct kmem_cache *s, void *p); @@ -422,11 +425,6 @@ extern void create_boot_cache(struct kmem_cache *, const char *name, unsigned int useroffset, unsigned int usersize); int slab_unmergeable(struct kmem_cache *s); -struct kmem_cache *find_mergeable(unsigned size, unsigned align, - slab_flags_t flags, const char *name, void (*ctor)(void *)); -struct kmem_cache * -__kmem_cache_alias(const char *name, unsigned int size, unsigned int align, - slab_flags_t flags, void (*ctor)(void *)); slab_flags_t kmem_cache_flags(slab_flags_t flags, const char *name); diff --git a/mm/slab_common.c b/mm/slab_common.c index 085af9a96fd92..edd49796be4c9 100644 --- a/mm/slab_common.c +++ b/mm/slab_common.c @@ -175,15 +175,22 @@ int slab_unmergeable(struct kmem_cache *s) return 0; } -struct kmem_cache *find_mergeable(unsigned int size, unsigned int align, - slab_flags_t flags, const char *name, void (*ctor)(void *)) +static struct kmem_cache *find_mergeable(unsigned int size, slab_flags_t flags, + const char *name, struct kmem_cache_args *args) { struct kmem_cache *s; + unsigned int align; if (slab_nomerge) return NULL; - if (ctor) + if (args->ctor) + return NULL; + + if (IS_ENABLED(CONFIG_HARDENED_USERCOPY) && args->usersize) + return NULL; + + if (args->sheaf_capacity) return NULL; flags = kmem_cache_flags(flags, name); @@ -192,7 +199,7 @@ struct kmem_cache *find_mergeable(unsigned int size, unsigned int align, return NULL; size = ALIGN(size, sizeof(void *)); - align = calculate_alignment(flags, align, size); + align = calculate_alignment(flags, args->align, size); size = ALIGN(size, align); list_for_each_entry_reverse(s, &slab_caches, list) { @@ -253,6 +260,31 @@ static struct kmem_cache *create_cache(const char *name, return ERR_PTR(err); } +static struct kmem_cache * +__kmem_cache_alias(const char *name, unsigned int size, slab_flags_t flags, + struct kmem_cache_args *args) +{ + struct kmem_cache *s; + + s = find_mergeable(size, flags, name, args); + if (s) { + if (sysfs_slab_alias(s, name)) + pr_err("SLUB: Unable to add cache alias %s to sysfs\n", + name); + + s->refcount++; + + /* + * Adjust the object sizes so that we clear + * the complete object on kzalloc. + */ + s->object_size = max(s->object_size, size); + s->inuse = max(s->inuse, ALIGN(size, sizeof(void *))); + } + + return s; +} + /** * __kmem_cache_create_args - Create a kmem cache. * @name: A string which is used in /proc/slabinfo to identify this cache. @@ -324,9 +356,7 @@ struct kmem_cache *__kmem_cache_create_args(const char *name, object_size - args->usersize < args->useroffset)) args->usersize = args->useroffset = 0; - if (!args->usersize && !args->sheaf_capacity) - s = __kmem_cache_alias(name, object_size, args->align, flags, - args->ctor); + s = __kmem_cache_alias(name, object_size, flags, args); if (s) goto out_unlock; diff --git a/mm/slub.c b/mm/slub.c index 5ddd2a5c9e79b..32d6b238e5088 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -351,11 +351,8 @@ enum track_item { TRACK_ALLOC, TRACK_FREE }; #ifdef SLAB_SUPPORTS_SYSFS static int sysfs_slab_add(struct kmem_cache *); -static int sysfs_slab_alias(struct kmem_cache *, const char *); #else static inline int sysfs_slab_add(struct kmem_cache *s) { return 0; } -static inline int sysfs_slab_alias(struct kmem_cache *s, const char *p) - { return 0; } #endif #if defined(CONFIG_DEBUG_FS) && defined(CONFIG_SLUB_DEBUG) @@ -8533,31 +8530,6 @@ void __init kmem_cache_init_late(void) #endif } -struct kmem_cache * -__kmem_cache_alias(const char *name, unsigned int size, unsigned int align, - slab_flags_t flags, void (*ctor)(void *)) -{ - struct kmem_cache *s; - - s = find_mergeable(size, align, flags, name, ctor); - if (s) { - if (sysfs_slab_alias(s, name)) - pr_err("SLUB: Unable to add cache alias %s to sysfs\n", - name); - - s->refcount++; - - /* - * Adjust the object sizes so that we clear - * the complete object on kzalloc. - */ - s->object_size = max(s->object_size, size); - s->inuse = max(s->inuse, ALIGN(size, sizeof(void *))); - } - - return s; -} - int do_kmem_cache_create(struct kmem_cache *s, const char *name, unsigned int size, struct kmem_cache_args *args, slab_flags_t flags) @@ -9790,7 +9762,7 @@ struct saved_alias { static struct saved_alias *alias_list; -static int sysfs_slab_alias(struct kmem_cache *s, const char *name) +int sysfs_slab_alias(struct kmem_cache *s, const char *name) { struct saved_alias *al; -- 2.53.0