From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 0A06C3AD538; Thu, 14 May 2026 05:08:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778735287; cv=none; b=GxRvlO+Tkr+zdOR9qm8W/xK/h3qrgFSTs7UYQ6exML+Ohm/bFuxXn+Jn5YsrKKmpiaGO3qrh1TjUhvCPya98FVcbknSaLIQUsRrbSMvuuYpTFe3uvvbCP/8rw+L/cUUEOLjNi6TE2fopDa/Ni9uxP7SXia+FDyK7tqNx+Dlc8RM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778735287; c=relaxed/simple; bh=i4bByhR3/GFn5EdsOuSs2aNtMnt37PAf+rz4tzgOO5w=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=CUco6YYjgYweEiJlnKEKBzRQ6jIOun1TPUfC3kAEqUYiMECQ5bSc2t8ihAC9vnaI5+SU+MhViuKQpEnfXep6VTkEyIN6i8M4e5bsMe9EG6HCeP0WuN0cddJ0hoDQJEGbD8AfZuZ7Nd7U/HZltmJ+woMwBxqqUcQrx1pLJAER+Yo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b=cJgfkrqj; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b="cJgfkrqj" Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 0CCA61655; Wed, 13 May 2026 22:08:00 -0700 (PDT) Received: from entos-yitian-01.Arm.com (unknown [10.168.197.54]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id E2E9F3F7B4; Wed, 13 May 2026 22:07:50 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1778735285; bh=i4bByhR3/GFn5EdsOuSs2aNtMnt37PAf+rz4tzgOO5w=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=cJgfkrqjF4tm9WRMUGgxzSWx/aIjRhFMv+ZZmwwkUccWMLOjzt+2qB/zt9dbgQKnT VFVuNrhwmSE2wQVt7y+3ZuYXRDIB5w+f3SKI5bKovaizZe7rdeyjGhvmf0WxlXiRVm U9BO0xWYArD/yhGbOFKPq0eNKZMHnjJbZ7Tn/0fM= From: Jia He To: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-perf-users@vger.kernel.org, linux-kselftest@vger.kernel.org, kunit-dev@googlegroups.com, kasan-dev@googlegroups.com, linux-mm@kvack.org Cc: Arnd Bergmann , Greg Kroah-Hartman , Alexander Viro , Christian Brauner , Jan Kara , Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Namhyung Kim , Mark Rutland , Alexander Shishkin , Jiri Olsa , Ian Rogers , Adrian Hunter , James Clark , Brendan Higgins , David Gow , Rae Moar , Alexander Potapenko , Marco Elver , Dmitry Vyukov , Andrew Morton , Jia He , "Paul E. McKenney" , Petr Mladek , Kees Cook , David Disseldorp Subject: [PATCH 6/7] hw_breakpoint_test: fix test_many_cpus failure on large systems Date: Thu, 14 May 2026 05:04:54 +0000 Message-Id: <20260514050455.2954509-7-justin.he@arm.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20260514050455.2954509-1-justin.he@arm.com> References: <20260514050455.2954509-1-justin.he@arm.com> Precedence: bulk X-Mailing-List: linux-perf-users@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit On systems with many CPUs (e.g. 128 cores x 4 HW breakpoint slots = 512 = MAX_TEST_BREAKPOINTS), test_many_cpus() advances idx to MAX_TEST_BREAKPOINTS after the last fill_bp_slots(). The subsequent register_test_bp() call hits WARN_ON(idx >= MAX_TEST_BREAKPOINTS), returns NULL, and the -ENOSPC expectation fails. Bail out of the loop when idx reaches the limit. Earlier iterations already validate the NOSPC path on other CPUs. To: Peter Zijlstra To: Ingo Molnar To: Arnaldo Carvalho de Melo To: Namhyung Kim To: Mark Rutland To: Alexander Shishkin To: Jiri Olsa To: Ian Rogers To: Adrian Hunter To: James Clark Cc: linux-perf-users@vger.kernel.org Signed-off-by: Jia He --- kernel/events/hw_breakpoint_test.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/kernel/events/hw_breakpoint_test.c b/kernel/events/hw_breakpoint_test.c index 2cfeeecf8de9..943d040d2224 100644 --- a/kernel/events/hw_breakpoint_test.c +++ b/kernel/events/hw_breakpoint_test.c @@ -137,6 +137,9 @@ static void test_many_cpus(struct kunit *test) for_each_online_cpu(cpu) { bool do_continue = fill_bp_slots(test, &idx, cpu, NULL, 0); + if (idx >= MAX_TEST_BREAKPOINTS) + break; + TEST_EXPECT_NOSPC(register_test_bp(cpu, NULL, idx)); if (!do_continue) break; -- 2.34.1