Re: [PATCH v1 2/9] selftests: kvm: s390: Add kvm_s390_sie_block definition for userspace tests

On Tue, 9 Jul 2024 17:40:22 +0200 Claudio Imbrenda imbrenda@linux.ibm.com wrote:

On Tue, 9 Jul 2024 14:56:57 +0200 Christoph Schlameuss schlameuss@linux.ibm.com wrote:

...

Subsequent tests do require direct manipulation of the SIE instruction. This commit introduces the SIE definition for the selftests.

There are already definitions of this within the kernel. This differs in two ways.

• This is the first definition of this in userspace.
• This does not require atomicity for the flags.

you say this here,

[...]

...

+#define PROG_BLOCK_SIE BIT(0) +#define PROG_REQUEST BIT(1)

• atomic_t prog20; /* 0x0020 */

but then you define this as atomic.

Is this a mistake, or is there a good reason?

[...]

Yes, this was an oversight. Will correct that to __u32 in the next version.

Christoph