linux-kernel - Re: [PATCH 3/4] KVM: s390: selftests: Use TAP interface in the tprot test

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Thu, 14 Apr 2022 14:08:19 +0200
From:   Thomas Huth <thuth@...hat.com>
To:     Claudio Imbrenda <imbrenda@...ux.ibm.com>,
        Janis Schoetterl-Glausch <scgl@...ux.ibm.com>
Cc:     kvm@...r.kernel.org,
        Christian Borntraeger <borntraeger@...ux.ibm.com>,
        Janosch Frank <frankja@...ux.ibm.com>,
        linux-kselftest@...r.kernel.org, linux-kernel@...r.kernel.org,
        David Hildenbrand <david@...hat.com>,
        Paolo Bonzini <pbonzini@...hat.com>,
        Shuah Khan <shuah@...nel.org>
Subject: Re: [PATCH 3/4] KVM: s390: selftests: Use TAP interface in the tprot
 test

On 14/04/2022 13.51, Claudio Imbrenda wrote:
> On Thu, 14 Apr 2022 12:53:21 +0200
> Thomas Huth <thuth@...hat.com> wrote:
> 
>> The tprot test currently does not have any output (unless one of
>> the TEST_ASSERT statement fails), so it's hard to say for a user
>> whether a certain new sub-test has been included in the binary or
>> not. Let's make this a little bit more user-friendly and include
>> some TAP output via the kselftests.h interface.
>>
>> Signed-off-by: Thomas Huth <thuth@...hat.com>
>> ---
>>   tools/testing/selftests/kvm/s390x/tprot.c | 12 +++++++++++-
>>   1 file changed, 11 insertions(+), 1 deletion(-)
>>
>> diff --git a/tools/testing/selftests/kvm/s390x/tprot.c b/tools/testing/selftests/kvm/s390x/tprot.c
>> index c097b9db495e..a714b4206e95 100644
>> --- a/tools/testing/selftests/kvm/s390x/tprot.c
>> +++ b/tools/testing/selftests/kvm/s390x/tprot.c
>> @@ -8,6 +8,7 @@
>>   #include <sys/mman.h>
>>   #include "test_util.h"
>>   #include "kvm_util.h"
>> +#include "kselftest.h"
>>   
>>   #define PAGE_SHIFT 12
>>   #define PAGE_SIZE (1 << PAGE_SHIFT)
>> @@ -69,6 +70,7 @@ enum stage {
>>   	STAGE_INIT_FETCH_PROT_OVERRIDE,
>>   	TEST_FETCH_PROT_OVERRIDE,
>>   	TEST_STORAGE_PROT_OVERRIDE,
>> +	NUM_STAGES			/* this must be the last entry */
>>   };
>>   
>>   struct test {
>> @@ -196,6 +198,7 @@ static void guest_code(void)
>>   	}									\
>>   	ASSERT_EQ(uc.cmd, UCALL_SYNC);						\
>>   	ASSERT_EQ(uc.args[1], __stage);						\
>> +	ksft_test_result_pass("" #stage "\n");					\
>>   })
>>   
>>   int main(int argc, char *argv[])
>> @@ -204,6 +207,9 @@ int main(int argc, char *argv[])
>>   	struct kvm_run *run;
>>   	vm_vaddr_t guest_0_page;
>>   
>> +	ksft_print_header();
>> +	ksft_set_plan(NUM_STAGES - 1);	/* STAGE_END is not counted, thus - 1 */
>> +
>>   	vm = vm_create_default(VCPU_ID, 0, guest_code);
>>   	run = vcpu_state(vm, VCPU_ID);
>>   
>> @@ -213,7 +219,7 @@ int main(int argc, char *argv[])
>>   
>>   	guest_0_page = vm_vaddr_alloc(vm, PAGE_SIZE, 0);
>>   	if (guest_0_page != 0)
>> -		print_skip("Did not allocate page at 0 for fetch protection override tests");
>> +		ksft_print_msg("Did not allocate page at 0 for fetch protection override tests\n");
> 
> will this print a skip, though?

No, it's now only a message.

> or you don't want to print a skip because then the numbering in the
> planning doesn't match anymore?

Right.

> in which case, is there an easy way to fix it?

Honestly, this part of the code is a little bit of a riddle to me - I wonder 
why this was using "print_skip()" at all, since the HOST_SYNC below is 
executed anyway... so this sounds rather like a warning message to me that 
says that the following test might not work as expected, instead of a real 
test-is-skipped message?

Janis, could you please clarify the intention here?

  Thomas

>>   	HOST_SYNC(vm, STAGE_INIT_FETCH_PROT_OVERRIDE);
>>   	if (guest_0_page == 0)
>>   		mprotect(addr_gva2hva(vm, (vm_vaddr_t)0), PAGE_SIZE, PROT_READ);
>> @@ -224,4 +230,8 @@ int main(int argc, char *argv[])
>>   	run->s.regs.crs[0] |= CR0_STORAGE_PROTECTION_OVERRIDE;
>>   	run->kvm_dirty_regs = KVM_SYNC_CRS;
>>   	HOST_SYNC(vm, TEST_STORAGE_PROT_OVERRIDE);
>> +
>> +	kvm_vm_free(vm);
>> +
>> +	ksft_finished();
>>   }
>