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 9121F38385; Wed, 17 Jul 2024 12:11:34 +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=1721218296; cv=none; b=tpe+I7S3gGdmxCLmJ7MqjQ1+SUE8pY/Qroxbpxmd3Jj+EID5cLSicqtDHBTAy7yzvTT4HzIQtNupBvjWQ+qfEkEkaPdNjPgJd6pPh7gCcvngfLjMBj7WVhRG3orAutkUkw+A2COUz1UsoT5pJh7wF+y9LXBFZW7hGN/2K3lbeLM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1721218296; c=relaxed/simple; bh=Cc2J6wmh/RMwK6UDOtUfqKU3tK1CB6zpaXWCypDmyLo=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=TCPU4hFr2Sm0sLbbbLijKMXQSkuP7F5ovA6qzXmvddd+GfuK10FpG1zU2trQcj07P01Bi4g/RCKNpIx/nrm5X1VBAZZsRW+6ConJqb3eYGnwlLSHDn5DFcMBQH5V4oT6HTIqAmahXgi7mCjDTS+8pek61tv7AfzIkSBxZYR+VmQ= 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; 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 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 0B9611063; Wed, 17 Jul 2024 05:11:59 -0700 (PDT) Received: from [10.162.43.24] (e116581.arm.com [10.162.43.24]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id EFF313F766; Wed, 17 Jul 2024 05:11:30 -0700 (PDT) Message-ID: <3782befb-c317-4bb0-a279-c90adb2ec47b@arm.com> Date: Wed, 17 Jul 2024 17:41:27 +0530 Precedence: bulk X-Mailing-List: linux-kselftest@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] selftests/mm: Skip test for non-LPA2 and non-LVA systems To: Ryan Roberts , akpm@linux-foundation.org, shuah@kernel.org Cc: linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-mm@kvack.org, Anshuman.Khandual@arm.com, broonie@kernel.org References: <20240717111011.316037-1-dev.jain@arm.com> Content-Language: en-US From: Dev Jain In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 7/17/24 17:27, Ryan Roberts wrote: > On 17/07/2024 12:10, Dev Jain wrote: >> Post my improvement of the test: >> https://lore.kernel.org/all/20240522070435.773918-3-dev.jain@arm.com/ >> The test begins to fail on 4k and 16k pages, on non-LPA2 systems. To >> reduce noise in the CI systems, let us skip the test when higher address >> space is not implemented. >> >> Signed-off-by: Dev Jain >> --- >> The patch applies on linux-next. >> >> tools/testing/selftests/mm/va_high_addr_switch.c | 14 +++++++++++++- >> 1 file changed, 13 insertions(+), 1 deletion(-) >> >> diff --git a/tools/testing/selftests/mm/va_high_addr_switch.c b/tools/testing/selftests/mm/va_high_addr_switch.c >> index fa7eabfaf841..c6040e1d6e53 100644 >> --- a/tools/testing/selftests/mm/va_high_addr_switch.c >> +++ b/tools/testing/selftests/mm/va_high_addr_switch.c >> @@ -293,6 +293,18 @@ static int run_test(struct testcase *test, int count) >> return ret; >> } >> >> +/* Check if userspace VA > 48 bits */ >> +static int high_address_present(void) >> +{ >> + void *ptr = mmap((void *)(1UL << 50), 1, PROT_READ | PROT_WRITE, >> + MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED, -1, 0); > I think there is (very unlikely) possibility that something is already mapped at > this address so it will be replaced due to MAP_FIXED. That could break the test. > But the only way something could be already mapped is if ARM64_FORCE_52BIT is > set and in that case, the test will fail anyway, right? So I think this is fine. The testcases already assume that high addresses must be empty. Yes, FORCE_52BIT is the only way something could already be mapped at high addresses, but in that case the test fails trivially. > >> + if (ptr == MAP_FAILED) >> + return 0; >> + >> + munmap(ptr, 1); >> + return 1; >> +} > I'm guessing this will cause a function-not-used warning on arches other than > arm64? Perhaps wrap it in `#ifdef __aarch64__`? Ah yes, I just checked and that is true. I shall post v2 in some time, shall wait if any more comments are there. > > Thanks, > Ryan > >> + >> static int supported_arch(void) >> { >> #if defined(__powerpc64__) >> @@ -300,7 +312,7 @@ static int supported_arch(void) >> #elif defined(__x86_64__) >> return 1; >> #elif defined(__aarch64__) >> - return 1; >> + return high_address_present(); >> #else >> return 0; >> #endif