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    SubjectRe: [PATCH v3 1/2] s390/setup: diag318: remove bit check and refactor struct
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    On 02.04.19 19:46, Collin Walling wrote:
    > Execution of DIAGNOSE 0x318 is fenced by checking an SCLP bit
    > for the availability of hardware support for the instruction.
    >
    > In order to support this instruction for a KVM/QEMU guest, we
    > would need to provide modifications to the SCLP Read SCP Info
    > data, which will in turn reduce the maximum number of CPUs that
    > may be provided to the guest. This issue introduces compatability
    > and legacy concerns.

    s/compatability/compatibility/

    >
    > Let's circumvent this issue by removing the bit check and blindly
    > executing the instruction. An exception table rule is in place to
    > catch the case where hardware does not support this instruction.

    Great, another ESSA like instruction...
    The sclp bit is still there but we can choose to ignore it for a spec
    exception.

    >
    > While we're at it, let's condense the version code fields in the
    > diag318_info struct until we can determine how it will be used.
    >
    > This modifies commit 4ad78b8651aacf26b3ab6d1e784952eb70469c43
    >
    > Signed-off-by: Collin Walling <walling@linux.ibm.com>

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