From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (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 6428C15C0 for ; Fri, 12 Sep 2025 01:37:48 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757641071; cv=none; b=eTDRtgCe78fd0XTEiFMeIDCVFM1qE+JBJ+AWQXFL3OptvRQEJuzp0FXmwQCE00UWVRDyAz3jQNXy5cni7UjBH6X5pd4TUNaoAymo0IWzKaWMk+E2IO5tvRoz1HnVOpsWk9im4YZQ1Z1XIPqFGk5aTML+pkqs3yAs8gnIepQ9mIs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757641071; c=relaxed/simple; bh=bp0U7YdJ9G9ovtdDdz6jrw8/OE9W6Ji5ywTshcRRp0w=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=iIbJSvlrAEiGaYzGkqTBKz4bb7oEpxW70XwShnt4g9ah71uUMXQndRJ4f4p1Yb+Mf6xqK69samT/yO6KUEC7GnnVDzsi9GsojfV6a/FHpKqAXH5NlXdQiY14zd5U42JT60/ILYUlt+0RxyR9f7LWt0BOeNlfPPEcqzCoagLZd9o= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=d6oS1ctG; arc=none smtp.client-ip=170.10.129.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="d6oS1ctG" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1757641067; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=+D1zQTiTnlEZqnFCgmfLcL4sMppDPwHxOoeZoJwx6to=; b=d6oS1ctG2WpsHfn2jUxL/AfvOL9eGA1nHThlNy0g1u1uc1EypktE7x8ob2ighapjFXf/Ok L+V4UKKHIT6XBF1sCMintmTyn2Bmq5c51WIWE3nvF9DVeFEpj47vEM8qE91UHWzrR9DBzM iOgaJ8vvfYnnJFYBnfrg+D9mig9mbYA= Received: from mx-prod-mc-05.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-641-1IyLpvnVOwmbrj65fPzDkQ-1; Thu, 11 Sep 2025 21:37:43 -0400 X-MC-Unique: 1IyLpvnVOwmbrj65fPzDkQ-1 X-Mimecast-MFC-AGG-ID: 1IyLpvnVOwmbrj65fPzDkQ_1757641062 Received: from mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.111]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 31BFA1955EA8; Fri, 12 Sep 2025 01:37:42 +0000 (UTC) Received: from dell-per7425-02.rhts.eng.pek2.redhat.com (dell-per7425-02.rhts.eng.pek2.redhat.com [10.73.116.18]) by mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 7A15B1800452; Fri, 12 Sep 2025 01:37:36 +0000 (UTC) From: Chunyu Hu To: akpm@linux-foundation.org, david@redhat.com, shuah@kernel.org, linux-mm@kvack.org Cc: linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org, lorenzo.stoakes@oracle.com, Liam.Howlett@oracle.com, vbabka@suse.cz, rppt@kernel.org, surenb@google.com, mhocko@suse.com, chuhu@redhat.com Subject: [PATCH v3 3/3] selftests/mm: fix va_high_addr_switch.sh failure on x86_64 Date: Fri, 12 Sep 2025 09:37:11 +0800 Message-ID: <20250912013711.3002969-4-chuhu@redhat.com> In-Reply-To: <20250912013711.3002969-3-chuhu@redhat.com> References: <20250912013711.3002969-1-chuhu@redhat.com> <20250912013711.3002969-2-chuhu@redhat.com> <20250912013711.3002969-3-chuhu@redhat.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.111 The test will fail as below on x86_64 with cpu la57 support (will skip if no la57 support). Note, the test requries nr_hugepages to be set first. # running bash ./va_high_addr_switch.sh # ------------------------------------- # mmap(addr_switch_hint - pagesize, pagesize): 0x7f55b60fa000 - OK # mmap(addr_switch_hint - pagesize, (2 * pagesize)): 0x7f55b60f9000 - OK # mmap(addr_switch_hint, pagesize): 0x800000000000 - OK # mmap(addr_switch_hint, 2 * pagesize, MAP_FIXED): 0x800000000000 - OK # mmap(NULL): 0x7f55b60f9000 - OK # mmap(low_addr): 0x40000000 - OK # mmap(high_addr): 0x1000000000000 - OK # mmap(high_addr) again: 0xffff55b6136000 - OK # mmap(high_addr, MAP_FIXED): 0x1000000000000 - OK # mmap(-1): 0xffff55b6134000 - OK # mmap(-1) again: 0xffff55b6132000 - OK # mmap(addr_switch_hint - pagesize, pagesize): 0x7f55b60fa000 - OK # mmap(addr_switch_hint - pagesize, 2 * pagesize): 0x7f55b60f9000 - OK # mmap(addr_switch_hint - pagesize/2 , 2 * pagesize): 0x7f55b60f7000 - OK # mmap(addr_switch_hint, pagesize): 0x800000000000 - OK # mmap(addr_switch_hint, 2 * pagesize, MAP_FIXED): 0x800000000000 - OK # mmap(NULL, MAP_HUGETLB): 0x7f55b5c00000 - OK # mmap(low_addr, MAP_HUGETLB): 0x40000000 - OK # mmap(high_addr, MAP_HUGETLB): 0x1000000000000 - OK # mmap(high_addr, MAP_HUGETLB) again: 0xffff55b5e00000 - OK # mmap(high_addr, MAP_FIXED | MAP_HUGETLB): 0x1000000000000 - OK # mmap(-1, MAP_HUGETLB): 0x7f55b5c00000 - OK # mmap(-1, MAP_HUGETLB) again: 0x7f55b5a00000 - OK # mmap(addr_switch_hint - pagesize, 2*hugepagesize, MAP_HUGETLB): 0x800000000000 - FAILED # mmap(addr_switch_hint , 2*hugepagesize, MAP_FIXED | MAP_HUGETLB): 0x800000000000 - OK # [FAIL] addr_switch_hint is defined as DFEFAULT_MAP_WINDOW in the failed test (for x86_64, DFEFAULT_MAP_WINDOW is defined as (1UL<<47) - pagesize) in 64 bit. Before commit cc92882ee218 ("mm: drop hugetlb_get_unmapped_area{_*} functions"), for x86_64 hugetlb_get_unmapped_area() is handled in arch code arch/x86/mm/hugetlbpage.c and addr is checked with map_address_hint_valid() after align with 'addr &= huge_page_mask(h)' which is a round down way, and it will fail the check because the addr is within the DEFAULT_MAP_WINDOW but (addr + len) is above the DFEFAULT_MAP_WINDOW. So it wil go through the hugetlb_get_unmmaped_area_top_down() to find an area within the DFEFAULT_MAP_WINDOW. After commit cc92882ee218 ("mm: drop hugetlb_get_unmapped_area{_*} functions"). The addr hint for hugetlb_get_unmmaped_area() will be rounded up and aligned to hugepage size with ALIGN() for all arches. And after the align, the addr will be above the default MAP_DEFAULT_WINDOW, and the map_addresshint_valid() check will pass because both aligned addr (addr0) and (addr + len) are above the DEFAULT_MAP_WINDOW, and the aligned hint address (0x800000000000) is returned as an suitable gap is found there, in arch_get_unmapped_area_topdown(). To still cover the case that addr is within the DEFAULT_MAP_WINDOW, and addr + len is above the DFEFAULT_MAP_WINDOW, change to choose the last hugepage aligned address within the DEFAULT_MAP_WINDOW as the hint addr, and the addr + len (2 hugepages) will be one hugepage above the DEFAULT_MAP_WINDOW. An aligned address won't be affected by the page round up or round down from kernel, so it's determistic. Fixes: cc92882ee218 ("mm: drop hugetlb_get_unmapped_area{_*} functions") Suggested-by: David Hildenbrand Signed-off-by: Chunyu Hu --- tools/testing/selftests/mm/va_high_addr_switch.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/tools/testing/selftests/mm/va_high_addr_switch.c b/tools/testing/selftests/mm/va_high_addr_switch.c index 896b3f73fc53..306eba825107 100644 --- a/tools/testing/selftests/mm/va_high_addr_switch.c +++ b/tools/testing/selftests/mm/va_high_addr_switch.c @@ -230,10 +230,10 @@ void testcases_init(void) .msg = "mmap(-1, MAP_HUGETLB) again", }, { - .addr = (void *)(addr_switch_hint - pagesize), + .addr = (void *)(addr_switch_hint - hugepagesize), .size = 2 * hugepagesize, .flags = MAP_HUGETLB | MAP_PRIVATE | MAP_ANONYMOUS, - .msg = "mmap(addr_switch_hint - pagesize, 2*hugepagesize, MAP_HUGETLB)", + .msg = "mmap(addr_switch_hint - hugepagesize, 2*hugepagesize, MAP_HUGETLB)", .low_addr_required = 1, .keep_mapped = 1, }, -- 2.49.0