From patchwork Fri Aug 4 09:11:33 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Leizhen (ThunderTown)" X-Patchwork-Id: 13341552 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2B5AEC001DE for ; Fri, 4 Aug 2023 09:11:58 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 38BEF2802E0; Fri, 4 Aug 2023 05:11:57 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 2EFC22802DF; Fri, 4 Aug 2023 05:11:57 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 054F92802E0; Fri, 4 Aug 2023 05:11:56 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0017.hostedemail.com [216.40.44.17]) by kanga.kvack.org (Postfix) with ESMTP id E69C32802DF for ; Fri, 4 Aug 2023 05:11:56 -0400 (EDT) Received: from smtpin24.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay05.hostedemail.com (Postfix) with ESMTP id B6D29409E1 for ; Fri, 4 Aug 2023 09:11:56 +0000 (UTC) X-FDA: 81085855032.24.E6FFA55 Received: from dggsgout11.his.huawei.com (dggsgout11.his.huawei.com [45.249.212.51]) by imf23.hostedemail.com (Postfix) with ESMTP id 37110140010 for ; Fri, 4 Aug 2023 09:11:52 +0000 (UTC) Authentication-Results: imf23.hostedemail.com; dkim=none; dmarc=none; spf=none (imf23.hostedemail.com: domain of thunder.leizhen@huaweicloud.com has no SPF policy when checking 45.249.212.51) smtp.mailfrom=thunder.leizhen@huaweicloud.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1691140314; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=qH2Y3/xOMWgj3UzJQddM1wfI9s1KetFUbEB44vBr0Q0=; b=pYkjkvpeOcLPVeHkqwOj7zt2wy8gyLFSVpTdAN5wNMA4GOksl7G9G+RcXCcSsBagflDeSC VynZN2MhDO/clJFblknPNZqz9AJyPyKrc+ApXCpEumxEn2sgBVMuyTsuPFcsmIQ5Dl1txl iKHN+4g7ho94DkQfNVt096YB6jdyunM= ARC-Authentication-Results: i=1; imf23.hostedemail.com; dkim=none; dmarc=none; spf=none (imf23.hostedemail.com: domain of thunder.leizhen@huaweicloud.com has no SPF policy when checking 45.249.212.51) smtp.mailfrom=thunder.leizhen@huaweicloud.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1691140314; a=rsa-sha256; cv=none; b=pe45eGxuywAOzldRK+uhJZT1AP9WBN4F7KuklzBUMhFDVU0nmycN4yQzM/ZdqyFAUqcKyn x/Y6JglJp0oJmFgPmfw8ATduUMIOtY94Oq6eQcoI/snaM7EsXcEZsjwmwHXa8/h4Z5Dk3U TuenMdp7Of2PPSNANEBwKStKobRmflU= Received: from mail02.huawei.com (unknown [172.30.67.143]) by dggsgout11.his.huawei.com (SkyGuard) with ESMTP id 4RHKhy0Tdfz4f3lCq for ; Fri, 4 Aug 2023 17:11:46 +0800 (CST) Received: from huaweicloud.com (unknown [10.174.178.55]) by APP4 (Coremail) with SMTP id gCh0CgBH_rHLwMxk2KskPg--.58335S7; Fri, 04 Aug 2023 17:11:47 +0800 (CST) From: thunder.leizhen@huaweicloud.com To: Petr Mladek , Sergey Senozhatsky , Steven Rostedt , John Ogness , Christoph Lameter , Pekka Enberg , David Rientjes , Joonsoo Kim , Andrew Morton , Vlastimil Babka , Roman Gushchin , Hyeonggon Yoo <42.hyeyoo@gmail.com>, linux-mm@kvack.org, "Paul E . 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So no one will call it directly. It is always necessary to call kmem_valid_obj() first to determine whether the passed pointer to a valid slab object. Then merging kmem_valid_obj() into kmem_dump_obj() will make the code more concise. So convert kmem_dump_obj() to work the same way as vmalloc_dump_obj(). After this, no one calls kmem_valid_obj() anymore, and it can be safely removed. Suggested-by: Matthew Wilcox Signed-off-by: Zhen Lei Reviewed-by: Matthew Wilcox (Oracle) Acked-by: Vlastimil Babka --- include/linux/slab.h | 5 +++-- mm/slab_common.c | 41 +++++++++++------------------------------ mm/util.c | 4 +--- 3 files changed, 15 insertions(+), 35 deletions(-) diff --git a/include/linux/slab.h b/include/linux/slab.h index 848c7c82ad5ad0b..d8ed2e810ec4448 100644 --- a/include/linux/slab.h +++ b/include/linux/slab.h @@ -244,8 +244,9 @@ DEFINE_FREE(kfree, void *, if (_T) kfree(_T)) size_t ksize(const void *objp); #ifdef CONFIG_PRINTK -bool kmem_valid_obj(void *object); -void kmem_dump_obj(void *object); +bool kmem_dump_obj(void *object); +#else +static inline bool kmem_dump_obj(void *object) { return false; } #endif /* diff --git a/mm/slab_common.c b/mm/slab_common.c index d1555ea2981ac51..ee6ed6dd7ba9fa5 100644 --- a/mm/slab_common.c +++ b/mm/slab_common.c @@ -528,26 +528,6 @@ bool slab_is_available(void) } #ifdef CONFIG_PRINTK -/** - * kmem_valid_obj - does the pointer reference a valid slab object? - * @object: pointer to query. - * - * Return: %true if the pointer is to a not-yet-freed object from - * kmalloc() or kmem_cache_alloc(), either %true or %false if the pointer - * is to an already-freed object, and %false otherwise. - */ -bool kmem_valid_obj(void *object) -{ - struct folio *folio; - - /* Some arches consider ZERO_SIZE_PTR to be a valid address. */ - if (object < (void *)PAGE_SIZE || !virt_addr_valid(object)) - return false; - folio = virt_to_folio(object); - return folio_test_slab(folio); -} -EXPORT_SYMBOL_GPL(kmem_valid_obj); - static void kmem_obj_info(struct kmem_obj_info *kpp, void *object, struct slab *slab) { if (__kfence_obj_info(kpp, object, slab)) @@ -566,11 +546,11 @@ static void kmem_obj_info(struct kmem_obj_info *kpp, void *object, struct slab * * and, if available, the slab name, return address, and stack trace from * the allocation and last free path of that object. * - * This function will splat if passed a pointer to a non-slab object. - * If you are not sure what type of object you have, you should instead - * use mem_dump_obj(). + * Return: %true if the pointer is to a not-yet-freed object from + * kmalloc() or kmem_cache_alloc(), either %true or %false if the pointer + * is to an already-freed object, and %false otherwise. */ -void kmem_dump_obj(void *object) +bool kmem_dump_obj(void *object) { char *cp = IS_ENABLED(CONFIG_MMU) ? "" : "/vmalloc"; int i; @@ -578,13 +558,13 @@ void kmem_dump_obj(void *object) unsigned long ptroffset; struct kmem_obj_info kp = { }; - if (WARN_ON_ONCE(!virt_addr_valid(object))) - return; + /* Some arches consider ZERO_SIZE_PTR to be a valid address. */ + if (object < (void *)PAGE_SIZE || !virt_addr_valid(object)) + return false; slab = virt_to_slab(object); - if (WARN_ON_ONCE(!slab)) { - pr_cont(" non-slab memory.\n"); - return; - } + if (!slab) + return false; + kmem_obj_info(&kp, object, slab); if (kp.kp_slab_cache) pr_cont(" slab%s %s", cp, kp.kp_slab_cache->name); @@ -621,6 +601,7 @@ void kmem_dump_obj(void *object) pr_info(" %pS\n", kp.kp_free_stack[i]); } + return true; } EXPORT_SYMBOL_GPL(kmem_dump_obj); #endif diff --git a/mm/util.c b/mm/util.c index dd12b9531ac4cad..ddfbb22dc1876d3 100644 --- a/mm/util.c +++ b/mm/util.c @@ -1063,10 +1063,8 @@ void mem_dump_obj(void *object) { const char *type; - if (kmem_valid_obj(object)) { - kmem_dump_obj(object); + if (kmem_dump_obj(object)) return; - } if (vmalloc_dump_obj(object)) return;