diff options
Diffstat (limited to 'arch/powerpc/kvm/book3s_hv_rmhandlers.S')
| -rw-r--r-- | arch/powerpc/kvm/book3s_hv_rmhandlers.S | 116 |
1 files changed, 92 insertions, 24 deletions
diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S index 07c8b5b0f9d2..868347ef09fd 100644 --- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S +++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S @@ -86,6 +86,12 @@ END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_207S) lbz r4, LPPACA_PMCINUSE(r3) cmpwi r4, 0 beq 23f /* skip if not */ +BEGIN_FTR_SECTION + ld r3, HSTATE_MMCR(r13) + andi. r4, r3, MMCR0_PMAO_SYNC | MMCR0_PMAO + cmpwi r4, MMCR0_PMAO + beql kvmppc_fix_pmao +END_FTR_SECTION_IFSET(CPU_FTR_PMAO_BUG) lwz r3, HSTATE_PMC(r13) lwz r4, HSTATE_PMC + 4(r13) lwz r5, HSTATE_PMC + 8(r13) @@ -286,8 +292,7 @@ kvm_start_guest: beq kvm_no_guest /* Set HSTATE_DSCR(r13) to something sensible */ - LOAD_REG_ADDR(r6, dscr_default) - ld r6, 0(r6) + ld r6, PACA_DSCR(r13) std r6, HSTATE_DSCR(r13) bl kvmppc_hv_entry @@ -737,6 +742,12 @@ skip_tm: sldi r3, r3, 31 /* MMCR0_FC (freeze counters) bit */ mtspr SPRN_MMCR0, r3 /* freeze all counters, disable ints */ isync +BEGIN_FTR_SECTION + ld r3, VCPU_MMCR(r4) + andi. r5, r3, MMCR0_PMAO_SYNC | MMCR0_PMAO + cmpwi r5, MMCR0_PMAO + beql kvmppc_fix_pmao +END_FTR_SECTION_IFSET(CPU_FTR_PMAO_BUG) lwz r3, VCPU_PMC(r4) /* always load up guest PMU registers */ lwz r5, VCPU_PMC + 4(r4) /* to prevent information leak */ lwz r6, VCPU_PMC + 8(r4) @@ -1439,6 +1450,30 @@ END_FTR_SECTION_IFCLR(CPU_FTR_TM) 25: /* Save PMU registers if requested */ /* r8 and cr0.eq are live here */ +BEGIN_FTR_SECTION + /* + * POWER8 seems to have a hardware bug where setting + * MMCR0[PMAE] along with MMCR0[PMC1CE] and/or MMCR0[PMCjCE] + * when some counters are already negative doesn't seem + * to cause a performance monitor alert (and hence interrupt). + * The effect of this is that when saving the PMU state, + * if there is no PMU alert pending when we read MMCR0 + * before freezing the counters, but one becomes pending + * before we read the counters, we lose it. + * To work around this, we need a way to freeze the counters + * before reading MMCR0. Normally, freezing the counters + * is done by writing MMCR0 (to set MMCR0[FC]) which + * unavoidably writes MMCR0[PMA0] as well. On POWER8, + * we can also freeze the counters using MMCR2, by writing + * 1s to all the counter freeze condition bits (there are + * 9 bits each for 6 counters). + */ + li r3, -1 /* set all freeze bits */ + clrrdi r3, r3, 10 + mfspr r10, SPRN_MMCR2 + mtspr SPRN_MMCR2, r3 + isync +END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S) li r3, 1 sldi r3, r3, 31 /* MMCR0_FC (freeze counters) bit */ mfspr r4, SPRN_MMCR0 /* save MMCR0 */ @@ -1462,6 +1497,9 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_206) std r4, VCPU_MMCR(r9) std r5, VCPU_MMCR + 8(r9) std r6, VCPU_MMCR + 16(r9) +BEGIN_FTR_SECTION + std r10, VCPU_MMCR + 24(r9) +END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S) std r7, VCPU_SIAR(r9) std r8, VCPU_SDAR(r9) mfspr r3, SPRN_PMC1 @@ -1485,12 +1523,10 @@ BEGIN_FTR_SECTION stw r11, VCPU_PMC + 28(r9) END_FTR_SECTION_IFSET(CPU_FTR_ARCH_201) BEGIN_FTR_SECTION - mfspr r4, SPRN_MMCR2 mfspr r5, SPRN_SIER mfspr r6, SPRN_SPMC1 mfspr r7, SPRN_SPMC2 mfspr r8, SPRN_MMCRS - std r4, VCPU_MMCR + 24(r9) std r5, VCPU_SIER(r9) stw r6, VCPU_PMC + 24(r9) stw r7, VCPU_PMC + 28(r9) @@ -1762,7 +1798,7 @@ kvmppc_hdsi: /* Search the hash table. */ mr r3, r9 /* vcpu pointer */ li r7, 1 /* data fault */ - bl .kvmppc_hpte_hv_fault + bl kvmppc_hpte_hv_fault ld r9, HSTATE_KVM_VCPU(r13) ld r10, VCPU_PC(r9) ld r11, VCPU_MSR(r9) @@ -1836,7 +1872,7 @@ kvmppc_hisi: mr r4, r10 mr r6, r11 li r7, 0 /* instruction fault */ - bl .kvmppc_hpte_hv_fault + bl kvmppc_hpte_hv_fault ld r9, HSTATE_KVM_VCPU(r13) ld r10, VCPU_PC(r9) ld r11, VCPU_MSR(r9) @@ -1910,16 +1946,16 @@ hcall_real_fallback: .globl hcall_real_table hcall_real_table: .long 0 /* 0 - unused */ - .long .kvmppc_h_remove - hcall_real_table - .long .kvmppc_h_enter - hcall_real_table - .long .kvmppc_h_read - hcall_real_table + .long DOTSYM(kvmppc_h_remove) - hcall_real_table + .long DOTSYM(kvmppc_h_enter) - hcall_real_table + .long DOTSYM(kvmppc_h_read) - hcall_real_table .long 0 /* 0x10 - H_CLEAR_MOD */ .long 0 /* 0x14 - H_CLEAR_REF */ - .long .kvmppc_h_protect - hcall_real_table - .long .kvmppc_h_get_tce - hcall_real_table - .long .kvmppc_h_put_tce - hcall_real_table + .long DOTSYM(kvmppc_h_protect) - hcall_real_table + .long DOTSYM(kvmppc_h_get_tce) - hcall_real_table + .long DOTSYM(kvmppc_h_put_tce) - hcall_real_table .long 0 /* 0x24 - H_SET_SPRG0 */ - .long .kvmppc_h_set_dabr - hcall_real_table + .long DOTSYM(kvmppc_h_set_dabr) - hcall_real_table .long 0 /* 0x2c */ .long 0 /* 0x30 */ .long 0 /* 0x34 */ @@ -1935,11 +1971,11 @@ hcall_real_table: .long 0 /* 0x5c */ .long 0 /* 0x60 */ #ifdef CONFIG_KVM_XICS - .long .kvmppc_rm_h_eoi - hcall_real_table - .long .kvmppc_rm_h_cppr - hcall_real_table - .long .kvmppc_rm_h_ipi - hcall_real_table + .long DOTSYM(kvmppc_rm_h_eoi) - hcall_real_table + .long DOTSYM(kvmppc_rm_h_cppr) - hcall_real_table + .long DOTSYM(kvmppc_rm_h_ipi) - hcall_real_table .long 0 /* 0x70 - H_IPOLL */ - .long .kvmppc_rm_h_xirr - hcall_real_table + .long DOTSYM(kvmppc_rm_h_xirr) - hcall_real_table #else .long 0 /* 0x64 - H_EOI */ .long 0 /* 0x68 - H_CPPR */ @@ -1973,7 +2009,7 @@ hcall_real_table: .long 0 /* 0xd4 */ .long 0 /* 0xd8 */ .long 0 /* 0xdc */ - .long .kvmppc_h_cede - hcall_real_table + .long DOTSYM(kvmppc_h_cede) - hcall_real_table .long 0 /* 0xe4 */ .long 0 /* 0xe8 */ .long 0 /* 0xec */ @@ -1990,11 +2026,11 @@ hcall_real_table: .long 0 /* 0x118 */ .long 0 /* 0x11c */ .long 0 /* 0x120 */ - .long .kvmppc_h_bulk_remove - hcall_real_table + .long DOTSYM(kvmppc_h_bulk_remove) - hcall_real_table .long 0 /* 0x128 */ .long 0 /* 0x12c */ .long 0 /* 0x130 */ - .long .kvmppc_h_set_xdabr - hcall_real_table + .long DOTSYM(kvmppc_h_set_xdabr) - hcall_real_table hcall_real_table_end: ignore_hdec: @@ -2219,16 +2255,30 @@ kvm_cede_exit: /* Try to handle a machine check in real mode */ machine_check_realmode: mr r3, r9 /* get vcpu pointer */ - bl .kvmppc_realmode_machine_check + bl kvmppc_realmode_machine_check nop - cmpdi r3, 0 /* continue exiting from guest? */ + cmpdi r3, 0 /* Did we handle MCE ? */ ld r9, HSTATE_KVM_VCPU(r13) li r12, BOOK3S_INTERRUPT_MACHINE_CHECK - beq mc_cont + /* + * Deliver unhandled/fatal (e.g. UE) MCE errors to guest through + * machine check interrupt (set HSRR0 to 0x200). And for handled + * errors (no-fatal), just go back to guest execution with current + * HSRR0 instead of exiting guest. This new approach will inject + * machine check to guest for fatal error causing guest to crash. + * + * The old code used to return to host for unhandled errors which + * was causing guest to hang with soft lockups inside guest and + * makes it difficult to recover guest instance. + */ + ld r10, VCPU_PC(r9) + ld r11, VCPU_MSR(r9) + bne 2f /* Continue guest execution. */ /* If not, deliver a machine check. SRR0/1 are already set */ li r10, BOOK3S_INTERRUPT_MACHINE_CHECK + ld r11, VCPU_MSR(r9) bl kvmppc_msr_interrupt - b fast_interrupt_c_return +2: b fast_interrupt_c_return /* * Check the reason we woke from nap, and take appropriate action. @@ -2431,3 +2481,21 @@ kvmppc_msr_interrupt: li r0, 1 1: rldimi r11, r0, MSR_TS_S_LG, 63 - MSR_TS_T_LG blr + +/* + * This works around a hardware bug on POWER8E processors, where + * writing a 1 to the MMCR0[PMAO] bit doesn't generate a + * performance monitor interrupt. Instead, when we need to have + * an interrupt pending, we have to arrange for a counter to overflow. + */ +kvmppc_fix_pmao: + li r3, 0 + mtspr SPRN_MMCR2, r3 + lis r3, (MMCR0_PMXE | MMCR0_FCECE)@h + ori r3, r3, MMCR0_PMCjCE | MMCR0_C56RUN + mtspr SPRN_MMCR0, r3 + lis r3, 0x7fff + ori r3, r3, 0xffff + mtspr SPRN_PMC6, r3 + isync + blr |