Re: [PATCH v2 0/2] KVM: s390: fix ESSA addressing exception injection in migration mode

[Christian Borntraeger <borntraeger@linux.ibm.com>]

Am 15.10.26 um 12:48 schrieb Gautam Gala:
> ESSA emulation in migration mode silently dropped addressing exceptions
> when the guest page-table walk failed, so the guest never received the
> expected PGM_ADDRESSING interrupt during live migration.
> 
> Patch 1 fixes dat_perform_essa() to return PGM_ADDRESSING on a walk
> failure, and __do_essa() to inject the program interrupt when it sees
> that return value.
> 
> Patch 2 adds a regression test integrated into the existing cmma_test
> selftest.
> 
> Changes since v1:
>   - dat_perform_essa() now returns +PGM_ADDRESSING instead of
>     -PGM_ADDRESSING; kvm_s390_inject_program_int() takes an unsigned u16
>     so passing -5 would have wrapped to 0xFFFB and injected a bogus PIC.
>     __do_essa() comparison and inject call updated accordingly. The
>     kernel-doc return-value entry is corrected to %PGM_ADDRESSING.
>   - Selftest: pgm_handler_c() now reads the actual PIC from lowcore
>     (__LC_PGM_INT_CODE) instead of hard-coding PGM_ADDRESSING, so the
>     test would have caught the sign error above had it been in v1.
>   - Selftest: virt_map(vm, 0, 0, 1) added so the DAT-on guest can
>     access the lowcore to read the PIC.
>   - Selftest: PGM_ADDRESSING, __LC_PGM_INT_CODE and __LC_PGM_NEW_PSW
>     constants moved to the shared s390/processor.h header.
>   - Selftest: SIGALRM/alarm() timeout wrapper removed.
> 
> Gautam Gala (2):
>    KVM: s390: fix ESSA addressing exception injection in migration mode
>    KVM: s390: selftests: add ESSA migration mode PGM_ADDRESSING
>      regression test
> 
>   arch/s390/kvm/gmap/dat.c                      |  5 +-
>   arch/s390/kvm/s390/priv.c                     |  2 +
>   .../selftests/kvm/include/s390/processor.h    |  7 ++
>   tools/testing/selftests/kvm/s390/cmma_test.c  | 69 +++++++++++++++++++
>   4 files changed, 82 insertions(+), 1 deletion(-)
> 


Thanks, applied.