| Message ID | 20210716024310.164448-1-npiggin@gmail.com |
|---|---|
| State | New |
| Headers | show |
| Series | [1/2] KVM: PPC: Book3S: Fix CONFIG_TRANSACTIONAL_MEM=n crash | expand |
On Fri, 16 Jul 2021 12:43:09 +1000, Nicholas Piggin wrote: > When running CPU_FTR_P9_TM_HV_ASSIST, HFSCR[TM] is set for the guest > even if the host has CONFIG_TRANSACTIONAL_MEM=n, which causes it to be > unprepared to handle guest exits while transactional. > > Normal guests don't have a problem because the HTM capability will not > be advertised, but a rogue or buggy one could crash the host. Applied to powerpc/fixes. [1/2] KVM: PPC: Book3S: Fix CONFIG_TRANSACTIONAL_MEM=n crash https://git.kernel.org/powerpc/c/bd31ecf44b8e18ccb1e5f6b50f85de6922a60de3 [2/2] KVM: PPC: Fix kvm_arch_vcpu_ioctl vcpu_load leak https://git.kernel.org/powerpc/c/bc4188a2f56e821ea057aca6bf444e138d06c252 cheers
diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c index 1d1fcc290fca..085fb8ecbf68 100644 --- a/arch/powerpc/kvm/book3s_hv.c +++ b/arch/powerpc/kvm/book3s_hv.c @@ -2697,8 +2697,10 @@ static int kvmppc_core_vcpu_create_hv(struct kvm_vcpu *vcpu) HFSCR_DSCR | HFSCR_VECVSX | HFSCR_FP | HFSCR_PREFIX; if (cpu_has_feature(CPU_FTR_HVMODE)) { vcpu->arch.hfscr &= mfspr(SPRN_HFSCR); +#ifdef CONFIG_PPC_TRANSACTIONAL_MEM if (cpu_has_feature(CPU_FTR_P9_TM_HV_ASSIST)) vcpu->arch.hfscr |= HFSCR_TM; +#endif } if (cpu_has_feature(CPU_FTR_TM_COMP)) vcpu->arch.hfscr |= HFSCR_TM;
When running CPU_FTR_P9_TM_HV_ASSIST, HFSCR[TM] is set for the guest even if the host has CONFIG_TRANSACTIONAL_MEM=n, which causes it to be unprepared to handle guest exits while transactional. Normal guests don't have a problem because the HTM capability will not be advertised, but a rogue or buggy one could crash the host. Reported-by: Alexey Kardashevskiy <aik@ozlabs.ru> Fixes: 4bb3c7a0208f ("KVM: PPC: Book3S HV: Work around transactional memory bugs in POWER9") Signed-off-by: Nicholas Piggin <npiggin@gmail.com> --- arch/powerpc/kvm/book3s_hv.c | 2 ++ 1 file changed, 2 insertions(+)