From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 563B0C11F64 for ; Tue, 29 Jun 2021 02:34:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3797E61A2B for ; Tue, 29 Jun 2021 02:34:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231719AbhF2Cg6 (ORCPT ); Mon, 28 Jun 2021 22:36:58 -0400 Received: from mail.kernel.org ([198.145.29.99]:57688 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231348AbhF2Cg6 (ORCPT ); Mon, 28 Jun 2021 22:36:58 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id B0E4061D01; Tue, 29 Jun 2021 02:34:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1624934071; bh=s3DMTLDguA3IaORWDvA5wlpt8ywK2iHnUlAp02sd6Z8=; h=Date:From:To:Subject:In-Reply-To:From; b=MblIOzCbafMUdc1KzxWCpe6IrH6rWdMIY8oIBx2QcHJZ0+AIe5NqsBEDFL4ykrPGa kZD2kFzjyjtj4sd4X+VAr9203uF8otCKP3kqd+xhxcQfg5WLluPq5QKuiGN0HD9LMj 0FluzJSNzi8nuZD6wAJW58xoyhInQ4tC8d2yhGfA= Date: Mon, 28 Jun 2021 19:34:30 -0700 From: Andrew Morton To: akpm@linux-foundation.org, brendanhiggins@google.com, cl@linux.com, dlatypov@google.com, elver@google.com, glittao@gmail.com, iamjoonsoo.kim@lge.com, linux-mm@kvack.org, mm-commits@vger.kernel.org, penberg@kernel.org, rientjes@google.com, torvalds@linux-foundation.org, vbabka@suse.cz Subject: [patch 023/192] kunit: make test->lock irq safe Message-ID: <20210629023430.co47kw1oB%akpm@linux-foundation.org> In-Reply-To: <20210628193256.008961950a714730751c1423@linux-foundation.org> User-Agent: s-nail v14.8.16 Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org From: Vlastimil Babka Subject: kunit: make test->lock irq safe The upcoming SLUB kunit test will be calling kunit_find_named_resource() from a context with disabled interrupts. That means kunit's test->lock needs to be IRQ safe to avoid potential deadlocks and lockdep splats. This patch therefore changes the test->lock usage to spin_lock_irqsave() and spin_unlock_irqrestore(). Link: https://lkml.kernel.org/r/20210511150734.3492-1-glittao@gmail.com Signed-off-by: Vlastimil Babka Signed-off-by: Oliver Glitta Reviewed-by: Brendan Higgins Cc: Christoph Lameter Cc: Daniel Latypov Cc: David Rientjes Cc: Joonsoo Kim Cc: Marco Elver Cc: Pekka Enberg Signed-off-by: Andrew Morton --- include/kunit/test.h | 5 +++-- lib/kunit/test.c | 18 +++++++++++------- 2 files changed, 14 insertions(+), 9 deletions(-) --- a/include/kunit/test.h~kunit-make-test-lock-irq-safe +++ a/include/kunit/test.h @@ -515,8 +515,9 @@ kunit_find_resource(struct kunit *test, void *match_data) { struct kunit_resource *res, *found = NULL; + unsigned long flags; - spin_lock(&test->lock); + spin_lock_irqsave(&test->lock, flags); list_for_each_entry_reverse(res, &test->resources, node) { if (match(test, res, (void *)match_data)) { @@ -526,7 +527,7 @@ kunit_find_resource(struct kunit *test, } } - spin_unlock(&test->lock); + spin_unlock_irqrestore(&test->lock, flags); return found; } --- a/lib/kunit/test.c~kunit-make-test-lock-irq-safe +++ a/lib/kunit/test.c @@ -475,6 +475,7 @@ int kunit_add_resource(struct kunit *tes void *data) { int ret = 0; + unsigned long flags; res->free = free; kref_init(&res->refcount); @@ -487,10 +488,10 @@ int kunit_add_resource(struct kunit *tes res->data = data; } - spin_lock(&test->lock); + spin_lock_irqsave(&test->lock, flags); list_add_tail(&res->node, &test->resources); /* refcount for list is established by kref_init() */ - spin_unlock(&test->lock); + spin_unlock_irqrestore(&test->lock, flags); return ret; } @@ -548,9 +549,11 @@ EXPORT_SYMBOL_GPL(kunit_alloc_and_get_re void kunit_remove_resource(struct kunit *test, struct kunit_resource *res) { - spin_lock(&test->lock); + unsigned long flags; + + spin_lock_irqsave(&test->lock, flags); list_del(&res->node); - spin_unlock(&test->lock); + spin_unlock_irqrestore(&test->lock, flags); kunit_put_resource(res); } EXPORT_SYMBOL_GPL(kunit_remove_resource); @@ -630,6 +633,7 @@ EXPORT_SYMBOL_GPL(kunit_kfree); void kunit_cleanup(struct kunit *test) { struct kunit_resource *res; + unsigned long flags; /* * test->resources is a stack - each allocation must be freed in the @@ -641,9 +645,9 @@ void kunit_cleanup(struct kunit *test) * protect against the current node being deleted, not the next. */ while (true) { - spin_lock(&test->lock); + spin_lock_irqsave(&test->lock, flags); if (list_empty(&test->resources)) { - spin_unlock(&test->lock); + spin_unlock_irqrestore(&test->lock, flags); break; } res = list_last_entry(&test->resources, @@ -654,7 +658,7 @@ void kunit_cleanup(struct kunit *test) * resource, and this can't happen if the test->lock * is held. */ - spin_unlock(&test->lock); + spin_unlock_irqrestore(&test->lock, flags); kunit_remove_resource(test, res); } current->kunit_test = NULL; _