Jordan Niethe 7fe4e1176d powerpc/kvm: Fix kvmppc_vcore->in_guest value in kvmhv_switch_to_host ... kvmhv_switch_to_host() in arch/powerpc/kvm/book3s_hv_rmhandlers.S needs to set kvmppc_vcore->in_guest to 0 to signal secondary CPUs to continue. This happens after resetting the PCR. Before commit 13c7bb3c57 ("powerpc/64s: Set reserved PCR bits"), r0 would always be 0 before it was stored to kvmppc_vcore->in_guest. However because of this change in the commit: /* Reset PCR */ ld r0, VCORE_PCR(r5) - cmpdi r0, 0 + LOAD_REG_IMMEDIATE(r6, PCR_MASK) + cmpld r0, r6 beq 18f - li r0, 0 - mtspr SPRN_PCR, r0 + mtspr SPRN_PCR, r6 18: /* Signal secondary CPUs to continue */ stb r0,VCORE_IN_GUEST(r5) We are no longer comparing r0 against 0 and loading it with 0 if it contains something else. Hence when we store r0 to kvmppc_vcore->in_guest, it might not be 0. This means that secondary CPUs will not be signalled to continue. Those CPUs get stuck and errors like the following are logged: KVM: CPU 1 seems to be stuck KVM: CPU 2 seems to be stuck KVM: CPU 3 seems to be stuck KVM: CPU 4 seems to be stuck KVM: CPU 5 seems to be stuck KVM: CPU 6 seems to be stuck KVM: CPU 7 seems to be stuck This can be reproduced with: $ for i in `seq 1 7` ; do chcpu -d $i ; done ; $ taskset -c 0 qemu-system-ppc64 -smp 8,threads=8 \ -M pseries,accel=kvm,kvm-type=HV -m 1G -nographic -vga none \ -kernel vmlinux -initrd initrd.cpio.xz Fix by making sure r0 is 0 before storing it to kvmppc_vcore->in_guest. Fixes: 13c7bb3c57 ("powerpc/64s: Set reserved PCR bits") Reported-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Jordan Niethe <jniethe5@gmail.com> Reviewed-by: Alistair Popple <alistair@popple.id.au> Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20191004025317.19340-1-jniethe5@gmail.com		2019-10-09 17:16:59 +11:00
..
book3s.c	kvm: x86, powerpc: do not allow clearing largepages debugfs entry	2019-09-30 18:52:00 +02:00
book3s.h
book3s_32_mmu.c
book3s_32_mmu_host.c
book3s_32_sr.S
book3s_64_mmu.c
book3s_64_mmu_host.c
book3s_64_mmu_hv.c
book3s_64_mmu_radix.c
book3s_64_slb.S
book3s_64_vio.c	KVM: PPC: Book3S: Invalidate multiple TCEs at once	2019-08-30 09:40:14 +10:00
book3s_64_vio_hv.c	KVM: PPC: Book3S: Invalidate multiple TCEs at once	2019-08-30 09:40:14 +10:00
book3s_emulate.c
book3s_exports.c
book3s_hv.c	powerpc/64s: Set reserved PCR bits	2019-09-21 08:36:53 +10:00
book3s_hv_builtin.c
book3s_hv_hmi.c
book3s_hv_interrupts.S
book3s_hv_nested.c	powerpc/64s: Set reserved PCR bits	2019-09-21 08:36:53 +10:00
book3s_hv_ras.c
book3s_hv_rm_mmu.c	powerpc/mm: Fixup tlbie vs mtpidr/mtlpidr ordering issue on POWER9	2019-09-24 20:58:55 +10:00
book3s_hv_rm_xics.c	KVM: PPC: Book3S HV: use smp_mb() when setting/clearing host_ipi flag	2019-09-24 12:46:26 +10:00
book3s_hv_rm_xive.c
book3s_hv_rmhandlers.S	powerpc/kvm: Fix kvmppc_vcore->in_guest value in kvmhv_switch_to_host	2019-10-09 17:16:59 +11:00
book3s_hv_tm.c
book3s_hv_tm_builtin.c
book3s_interrupts.S
book3s_mmu_hpte.c
book3s_paired_singles.c
book3s_pr.c
book3s_pr_papr.c
book3s_rmhandlers.S
book3s_rtas.c
book3s_segment.S
book3s_xics.c
book3s_xics.h
book3s_xive.c
book3s_xive.h
book3s_xive_native.c
book3s_xive_template.c
booke.c
booke.h
booke_emulate.c
booke_interrupts.S
bookehv_interrupts.S
e500.c
e500.h
e500_emulate.c
e500_mmu.c
e500_mmu_host.c
e500_mmu_host.h
e500mc.c
emulate.c
emulate_loadstore.c
fpu.S
irq.h
Kconfig
Makefile
mpic.c
powerpc.c	PPC KVM update for 5.4	2019-09-10 16:51:17 +02:00
timing.c
timing.h
tm.S
trace.h
trace_book3s.h
trace_booke.h
trace_hv.h
trace_pr.h