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author | Radim Krčmář <rkrcmar@redhat.com> | 2018-02-01 16:13:07 +0100 |
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committer | Radim Krčmář <rkrcmar@redhat.com> | 2018-02-01 16:13:07 +0100 |
commit | d2b9b2079e23c1ab80ce1d7670d5e1994468a881 (patch) | |
tree | bd9bfb74343da003b7bac0569d0a7f8025cbaef4 /arch/powerpc/kvm/book3s_hv_rmhandlers.S | |
parent | 7bf14c28ee776be567855bd39ed8ff795ea19f55 (diff) | |
parent | 9b9b13a6d1537ddc4caccd6f1c41b78edbc08437 (diff) | |
download | linux-stable-d2b9b2079e23c1ab80ce1d7670d5e1994468a881.tar.gz linux-stable-d2b9b2079e23c1ab80ce1d7670d5e1994468a881.tar.bz2 linux-stable-d2b9b2079e23c1ab80ce1d7670d5e1994468a881.zip |
Merge tag 'kvm-ppc-next-4.16-1' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc
PPC KVM update for 4.16
- Allow HPT guests to run on a radix host on POWER9 v2.2 CPUs
without requiring the complex thread synchronization that earlier
CPU versions required.
- A series from Ben Herrenschmidt to improve the handling of
escalation interrupts with the XIVE interrupt controller.
- Provide for the decrementer register to be copied across on
migration.
- Various minor cleanups and bugfixes.
Diffstat (limited to 'arch/powerpc/kvm/book3s_hv_rmhandlers.S')
-rw-r--r-- | arch/powerpc/kvm/book3s_hv_rmhandlers.S | 237 |
1 files changed, 154 insertions, 83 deletions
diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S index 9c61f736c75b..b64f10a5f5e7 100644 --- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S +++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S @@ -617,13 +617,6 @@ kvmppc_hv_entry: lbz r0, KVM_RADIX(r9) cmpwi cr7, r0, 0 - /* Clear out SLB if hash */ - bne cr7, 2f - li r6,0 - slbmte r6,r6 - slbia - ptesync -2: /* * POWER7/POWER8 host -> guest partition switch code. * We don't have to lock against concurrent tlbies, @@ -738,19 +731,6 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S) 10: cmpdi r4, 0 beq kvmppc_primary_no_guest kvmppc_got_guest: - - /* Load up guest SLB entries (N.B. slb_max will be 0 for radix) */ - lwz r5,VCPU_SLB_MAX(r4) - cmpwi r5,0 - beq 9f - mtctr r5 - addi r6,r4,VCPU_SLB -1: ld r8,VCPU_SLB_E(r6) - ld r9,VCPU_SLB_V(r6) - slbmte r9,r8 - addi r6,r6,VCPU_SLB_SIZE - bdnz 1b -9: /* Increment yield count if they have a VPA */ ld r3, VCPU_VPA(r4) cmpdi r3, 0 @@ -957,7 +937,6 @@ ALT_FTR_SECTION_END_IFCLR(CPU_FTR_ARCH_300) mftb r7 subf r3,r7,r8 mtspr SPRN_DEC,r3 - std r3,VCPU_DEC(r4) ld r5, VCPU_SPRG0(r4) ld r6, VCPU_SPRG1(r4) @@ -1018,6 +997,29 @@ ALT_FTR_SECTION_END_IFCLR(CPU_FTR_ARCH_300) cmpdi r3, 512 /* 1 microsecond */ blt hdec_soon + /* For hash guest, clear out and reload the SLB */ + ld r6, VCPU_KVM(r4) + lbz r0, KVM_RADIX(r6) + cmpwi r0, 0 + bne 9f + li r6, 0 + slbmte r6, r6 + slbia + ptesync + + /* Load up guest SLB entries (N.B. slb_max will be 0 for radix) */ + lwz r5,VCPU_SLB_MAX(r4) + cmpwi r5,0 + beq 9f + mtctr r5 + addi r6,r4,VCPU_SLB +1: ld r8,VCPU_SLB_E(r6) + ld r9,VCPU_SLB_V(r6) + slbmte r9,r8 + addi r6,r6,VCPU_SLB_SIZE + bdnz 1b +9: + #ifdef CONFIG_KVM_XICS /* We are entering the guest on that thread, push VCPU to XIVE */ ld r10, HSTATE_XIVE_TIMA_PHYS(r13) @@ -1031,8 +1033,53 @@ ALT_FTR_SECTION_END_IFCLR(CPU_FTR_ARCH_300) li r9, TM_QW1_OS + TM_WORD2 stwcix r11,r9,r10 li r9, 1 - stw r9, VCPU_XIVE_PUSHED(r4) + stb r9, VCPU_XIVE_PUSHED(r4) eieio + + /* + * We clear the irq_pending flag. There is a small chance of a + * race vs. the escalation interrupt happening on another + * processor setting it again, but the only consequence is to + * cause a spurrious wakeup on the next H_CEDE which is not an + * issue. + */ + li r0,0 + stb r0, VCPU_IRQ_PENDING(r4) + + /* + * In single escalation mode, if the escalation interrupt is + * on, we mask it. + */ + lbz r0, VCPU_XIVE_ESC_ON(r4) + cmpwi r0,0 + beq 1f + ld r10, VCPU_XIVE_ESC_RADDR(r4) + li r9, XIVE_ESB_SET_PQ_01 + ldcix r0, r10, r9 + sync + + /* We have a possible subtle race here: The escalation interrupt might + * have fired and be on its way to the host queue while we mask it, + * and if we unmask it early enough (re-cede right away), there is + * a theorical possibility that it fires again, thus landing in the + * target queue more than once which is a big no-no. + * + * Fortunately, solving this is rather easy. If the above load setting + * PQ to 01 returns a previous value where P is set, then we know the + * escalation interrupt is somewhere on its way to the host. In that + * case we simply don't clear the xive_esc_on flag below. It will be + * eventually cleared by the handler for the escalation interrupt. + * + * Then, when doing a cede, we check that flag again before re-enabling + * the escalation interrupt, and if set, we abort the cede. + */ + andi. r0, r0, XIVE_ESB_VAL_P + bne- 1f + + /* Now P is 0, we can clear the flag */ + li r0, 0 + stb r0, VCPU_XIVE_ESC_ON(r4) +1: no_xive: #endif /* CONFIG_KVM_XICS */ @@ -1193,7 +1240,7 @@ hdec_soon: addi r3, r4, VCPU_TB_RMEXIT bl kvmhv_accumulate_time #endif - b guest_exit_cont + b guest_bypass /****************************************************************************** * * @@ -1423,15 +1470,35 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300) blt deliver_guest_interrupt guest_exit_cont: /* r9 = vcpu, r12 = trap, r13 = paca */ + /* Save more register state */ + mfdar r6 + mfdsisr r7 + std r6, VCPU_DAR(r9) + stw r7, VCPU_DSISR(r9) + /* don't overwrite fault_dar/fault_dsisr if HDSI */ + cmpwi r12,BOOK3S_INTERRUPT_H_DATA_STORAGE + beq mc_cont + std r6, VCPU_FAULT_DAR(r9) + stw r7, VCPU_FAULT_DSISR(r9) + + /* See if it is a machine check */ + cmpwi r12, BOOK3S_INTERRUPT_MACHINE_CHECK + beq machine_check_realmode +mc_cont: +#ifdef CONFIG_KVM_BOOK3S_HV_EXIT_TIMING + addi r3, r9, VCPU_TB_RMEXIT + mr r4, r9 + bl kvmhv_accumulate_time +#endif #ifdef CONFIG_KVM_XICS /* We are exiting, pull the VP from the XIVE */ - lwz r0, VCPU_XIVE_PUSHED(r9) + lbz r0, VCPU_XIVE_PUSHED(r9) cmpwi cr0, r0, 0 beq 1f li r7, TM_SPC_PULL_OS_CTX li r6, TM_QW1_OS mfmsr r0 - andi. r0, r0, MSR_IR /* in real mode? */ + andi. r0, r0, MSR_DR /* in real mode? */ beq 2f ld r10, HSTATE_XIVE_TIMA_VIRT(r13) cmpldi cr0, r10, 0 @@ -1454,33 +1521,42 @@ guest_exit_cont: /* r9 = vcpu, r12 = trap, r13 = paca */ /* Fixup some of the state for the next load */ li r10, 0 li r0, 0xff - stw r10, VCPU_XIVE_PUSHED(r9) + stb r10, VCPU_XIVE_PUSHED(r9) stb r10, (VCPU_XIVE_SAVED_STATE+3)(r9) stb r0, (VCPU_XIVE_SAVED_STATE+4)(r9) eieio 1: #endif /* CONFIG_KVM_XICS */ - /* Save more register state */ - mfdar r6 - mfdsisr r7 - std r6, VCPU_DAR(r9) - stw r7, VCPU_DSISR(r9) - /* don't overwrite fault_dar/fault_dsisr if HDSI */ - cmpwi r12,BOOK3S_INTERRUPT_H_DATA_STORAGE - beq mc_cont - std r6, VCPU_FAULT_DAR(r9) - stw r7, VCPU_FAULT_DSISR(r9) - /* See if it is a machine check */ - cmpwi r12, BOOK3S_INTERRUPT_MACHINE_CHECK - beq machine_check_realmode -mc_cont: -#ifdef CONFIG_KVM_BOOK3S_HV_EXIT_TIMING - addi r3, r9, VCPU_TB_RMEXIT - mr r4, r9 - bl kvmhv_accumulate_time -#endif + /* For hash guest, read the guest SLB and save it away */ + ld r5, VCPU_KVM(r9) + lbz r0, KVM_RADIX(r5) + li r5, 0 + cmpwi r0, 0 + bne 3f /* for radix, save 0 entries */ + lwz r0,VCPU_SLB_NR(r9) /* number of entries in SLB */ + mtctr r0 + li r6,0 + addi r7,r9,VCPU_SLB +1: slbmfee r8,r6 + andis. r0,r8,SLB_ESID_V@h + beq 2f + add r8,r8,r6 /* put index in */ + slbmfev r3,r6 + std r8,VCPU_SLB_E(r7) + std r3,VCPU_SLB_V(r7) + addi r7,r7,VCPU_SLB_SIZE + addi r5,r5,1 +2: addi r6,r6,1 + bdnz 1b + /* Finally clear out the SLB */ + li r0,0 + slbmte r0,r0 + slbia + ptesync +3: stw r5,VCPU_SLB_MAX(r9) +guest_bypass: mr r3, r12 /* Increment exit count, poke other threads to exit */ bl kvmhv_commence_exit @@ -1501,31 +1577,6 @@ mc_cont: ori r6,r6,1 mtspr SPRN_CTRLT,r6 4: - /* Check if we are running hash or radix and store it in cr2 */ - ld r5, VCPU_KVM(r9) - lbz r0, KVM_RADIX(r5) - cmpwi cr2,r0,0 - - /* Read the guest SLB and save it away */ - li r5, 0 - bne cr2, 3f /* for radix, save 0 entries */ - lwz r0,VCPU_SLB_NR(r9) /* number of entries in SLB */ - mtctr r0 - li r6,0 - addi r7,r9,VCPU_SLB -1: slbmfee r8,r6 - andis. r0,r8,SLB_ESID_V@h - beq 2f - add r8,r8,r6 /* put index in */ - slbmfev r3,r6 - std r8,VCPU_SLB_E(r7) - std r3,VCPU_SLB_V(r7) - addi r7,r7,VCPU_SLB_SIZE - addi r5,r5,1 -2: addi r6,r6,1 - bdnz 1b -3: stw r5,VCPU_SLB_MAX(r9) - /* * Save the guest PURR/SPURR */ @@ -1803,7 +1854,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300) ld r5, VCPU_KVM(r9) lbz r0, KVM_RADIX(r5) cmpwi cr2, r0, 0 - beq cr2, 3f + beq cr2, 4f /* Radix: Handle the case where the guest used an illegal PID */ LOAD_REG_ADDR(r4, mmu_base_pid) @@ -1839,15 +1890,9 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300) BEGIN_FTR_SECTION PPC_INVALIDATE_ERAT END_FTR_SECTION_IFSET(CPU_FTR_POWER9_DD1) - b 4f +4: #endif /* CONFIG_PPC_RADIX_MMU */ - /* Hash: clear out SLB */ -3: li r5,0 - slbmte r5,r5 - slbia - ptesync -4: /* * POWER7/POWER8 guest -> host partition switch code. * We don't have to lock against tlbies but we do @@ -1908,16 +1953,17 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S) bne 27f bl kvmppc_realmode_hmi_handler nop + cmpdi r3, 0 li r12, BOOK3S_INTERRUPT_HMI /* - * At this point kvmppc_realmode_hmi_handler would have resync-ed - * the TB. Hence it is not required to subtract guest timebase - * offset from timebase. So, skip it. + * At this point kvmppc_realmode_hmi_handler may have resync-ed + * the TB, and if it has, we must not subtract the guest timebase + * offset from the timebase. So, skip it. * * Also, do not call kvmppc_subcore_exit_guest() because it has * been invoked as part of kvmppc_realmode_hmi_handler(). */ - b 30f + beq 30f 27: /* Subtract timebase offset from timebase */ @@ -2744,7 +2790,32 @@ kvm_cede_prodded: /* we've ceded but we want to give control to the host */ kvm_cede_exit: ld r9, HSTATE_KVM_VCPU(r13) - b guest_exit_cont +#ifdef CONFIG_KVM_XICS + /* Abort if we still have a pending escalation */ + lbz r5, VCPU_XIVE_ESC_ON(r9) + cmpwi r5, 0 + beq 1f + li r0, 0 + stb r0, VCPU_CEDED(r9) +1: /* Enable XIVE escalation */ + li r5, XIVE_ESB_SET_PQ_00 + mfmsr r0 + andi. r0, r0, MSR_DR /* in real mode? */ + beq 1f + ld r10, VCPU_XIVE_ESC_VADDR(r9) + cmpdi r10, 0 + beq 3f + ldx r0, r10, r5 + b 2f +1: ld r10, VCPU_XIVE_ESC_RADDR(r9) + cmpdi r10, 0 + beq 3f + ldcix r0, r10, r5 +2: sync + li r0, 1 + stb r0, VCPU_XIVE_ESC_ON(r9) +#endif /* CONFIG_KVM_XICS */ +3: b guest_exit_cont /* Try to handle a machine check in real mode */ machine_check_realmode: |