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| author | Nicholas Piggin <npiggin@gmail.com> | 2022-01-23 22:00:39 +1000 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2022-05-13 21:33:33 +1000 |
| commit | 5d506f159b2b9d0c9bee9bb43ccafb4f291143c2 (patch) | |
| tree | 3f1af91259d27e3c3b07e7400c36fe38207fec5c /arch/powerpc/kvm | |
| parent | 18827eeef022df43c1fdeca0fde00ca09405dff1 (diff) | |
| download | lwn-5d506f159b2b9d0c9bee9bb43ccafb4f291143c2.tar.gz lwn-5d506f159b2b9d0c9bee9bb43ccafb4f291143c2.zip | |
KVM: PPC: Book3S HV: Update LPID allocator init for POWER9, Nested
The LPID allocator init is changed to:
- use mmu_lpid_bits rather than hard-coding;
- use KVM_MAX_NESTED_GUESTS for nested hypervisors;
- not reserve the top LPID on POWER9 and newer CPUs.
The reserved LPID is made a POWER7/8-specific detail.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Fabiano Rosas <farosas@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220123120043.3586018-3-npiggin@gmail.com
Diffstat (limited to 'arch/powerpc/kvm')
| -rw-r--r-- | arch/powerpc/kvm/book3s_64_mmu_hv.c | 29 | ||||
| -rw-r--r-- | arch/powerpc/kvm/book3s_hv_rmhandlers.S | 8 |
2 files changed, 29 insertions, 8 deletions
diff --git a/arch/powerpc/kvm/book3s_64_mmu_hv.c b/arch/powerpc/kvm/book3s_64_mmu_hv.c index fed4b7652a95..b19347fa2076 100644 --- a/arch/powerpc/kvm/book3s_64_mmu_hv.c +++ b/arch/powerpc/kvm/book3s_64_mmu_hv.c @@ -256,7 +256,7 @@ void kvmppc_map_vrma(struct kvm_vcpu *vcpu, struct kvm_memory_slot *memslot, int kvmppc_mmu_hv_init(void) { - unsigned long rsvd_lpid; + unsigned long nr_lpids; if (!mmu_has_feature(MMU_FTR_LOCKLESS_TLBIE)) return -EINVAL; @@ -264,16 +264,29 @@ int kvmppc_mmu_hv_init(void) if (cpu_has_feature(CPU_FTR_HVMODE)) { if (WARN_ON(mfspr(SPRN_LPID) != 0)) return -EINVAL; + nr_lpids = 1UL << mmu_lpid_bits; + } else { + nr_lpids = KVM_MAX_NESTED_GUESTS; } - /* POWER8 and above have 12-bit LPIDs (10-bit in POWER7) */ - if (cpu_has_feature(CPU_FTR_ARCH_207S)) - rsvd_lpid = LPID_RSVD; - else - rsvd_lpid = LPID_RSVD_POWER7; + if (nr_lpids > KVMPPC_NR_LPIDS) + nr_lpids = KVMPPC_NR_LPIDS; + + if (!cpu_has_feature(CPU_FTR_ARCH_300)) { + /* POWER7 has 10-bit LPIDs, POWER8 has 12-bit LPIDs */ + if (cpu_has_feature(CPU_FTR_ARCH_207S)) + WARN_ON(nr_lpids != 1UL << 12); + else + WARN_ON(nr_lpids != 1UL << 10); + + /* + * Reserve the last implemented LPID use in partition + * switching for POWER7 and POWER8. + */ + nr_lpids -= 1; + } - /* rsvd_lpid is reserved for use in partition switching */ - kvmppc_init_lpid(rsvd_lpid); + kvmppc_init_lpid(nr_lpids); return 0; } diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S index d185dee26026..0c552885a032 100644 --- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S +++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S @@ -51,6 +51,14 @@ #define STACK_SLOT_FSCR (SFS-96) /* + * Use the last LPID (all implemented LPID bits = 1) for partition switching. + * This is reserved in the LPID allocator. POWER7 only implements 0x3ff, but + * we write 0xfff into the LPID SPR anyway, which seems to work and just + * ignores the top bits. + */ +#define LPID_RSVD 0xfff + +/* * Call kvmppc_hv_entry in real mode. * Must be called with interrupts hard-disabled. * |