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1f1ccb6f3c
The Container Id in a container-type TLE of SysIB_15x is defined as 8-bit
unsigned nonzero integer. Make stsi fc 15 emulation architecture compliant,
by starting the container ids at 1 for the lowest numbered container.
The qemu misbehaviour without this patch becomes obvious due to a recently
proposed kernel fix. Older linux kernels pass the container ids from stsi
fc15 unchanged to sysfs, i.e. starting at 1 on s390 hardware. This resulted
in off-by-one values when compared to the values from HMC. A Linux kernel
fix is being proposed to correct the sysfs topology ids by -1, so they
start at 0, e.g. when displayed by 'lscpu -ye'. In case a KVM guest with a
fixed kernel runs on a host with a qemu without this fix, this can result
in container ids erroneously being shown as 255.
Example (Fixed guest on unfixed qemu):
$ lscpu -ye
CPU NODE DRAWER BOOK SOCKET CORE L1d:L1i:L2 ONLINE CONFIGURED POLARIZATION ADDRESS
0 0 255 255 255 0 0:0:0 yes yes vert-medium 0
1 0 255 255 0 1 1:1:1 yes yes vert-medium 1
After this fix:
$ lscpu -ye
CPU NODE DRAWER BOOK SOCKET CORE L1d:L1i:L2 ONLINE CONFIGURED POLARIZATION ADDRESS
0 0 0 0 0 0 0:0:0 yes yes vert-medium 0
1 0 0 0 1 1 1:1:1 yes yes vert-medium 1
Fixes: f4f54b582f ("target/s390x/cpu topology: handle STSI(15) and build the SYSIB")
Signed-off-by: Alexandra Winter <wintera@linux.ibm.com>
Acked-by: Hendrik Brueckner <brueckner@linux.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Reviewed-by: Gautam Gala <ggala@linux.ibm.com>
Message-ID: <20260511134909.43802-1-wintera@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>