From: Alexander Graf <agraf@suse.de>
To: kvm-ppc@vger.kernel.org
Cc: kvm@vger.kernel.org, Paul Mackerras <paulus@samba.org>
Subject: [PATCH 49/56] KVM: PPC: Work around POWER7 DABR corruption problem
Date: Thu, 15 Mar 2012 12:11:18 +0000 [thread overview]
Message-ID: <1331813485-14722-50-git-send-email-agraf@suse.de> (raw)
In-Reply-To: <1331813485-14722-1-git-send-email-agraf@suse.de>
From: Paul Mackerras <paulus@samba.org>
It turns out that on POWER7, writing to the DABR can cause a corrupted
value to be written if the PMU is active and updating SDAR in continuous
sampling mode. To work around this, we make sure that the PMU is inactive
and SDAR updates are disabled (via MMCRA) when we are context-switching
DABR.
When the guest sets DABR via the H_SET_DABR hypercall, we use a slightly
different workaround, which is to read back the DABR and write it again
if it got corrupted.
While we are at it, make it consistent that the saving and restoring
of the guest's non-volatile GPRs and the FPRs are done with the guest
setup of the PMU active.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
---
arch/powerpc/kvm/book3s_hv_interrupts.S | 9 ++-
arch/powerpc/kvm/book3s_hv_rmhandlers.S | 93 ++++++++++++++++++-------------
2 files changed, 61 insertions(+), 41 deletions(-)
diff --git a/arch/powerpc/kvm/book3s_hv_interrupts.S b/arch/powerpc/kvm/book3s_hv_interrupts.S
index d3fb4df..84035a5 100644
--- a/arch/powerpc/kvm/book3s_hv_interrupts.S
+++ b/arch/powerpc/kvm/book3s_hv_interrupts.S
@@ -68,19 +68,24 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_206)
rotldi r10,r10,16
mtmsrd r10,1
- /* Save host PMU registers and load guest PMU registers */
+ /* Save host PMU registers */
/* R4 is live here (vcpu pointer) but not r3 or r5 */
li r3, 1
sldi r3, r3, 31 /* MMCR0_FC (freeze counters) bit */
mfspr r7, SPRN_MMCR0 /* save MMCR0 */
mtspr SPRN_MMCR0, r3 /* freeze all counters, disable interrupts */
+ mfspr r6, SPRN_MMCRA
+BEGIN_FTR_SECTION
+ /* On P7, clear MMCRA in order to disable SDAR updates */
+ li r5, 0
+ mtspr SPRN_MMCRA, r5
+END_FTR_SECTION_IFSET(CPU_FTR_ARCH_206)
isync
ld r3, PACALPPACAPTR(r13) /* is the host using the PMU? */
lbz r5, LPPACA_PMCINUSE(r3)
cmpwi r5, 0
beq 31f /* skip if not */
mfspr r5, SPRN_MMCR1
- mfspr r6, SPRN_MMCRA
std r7, HSTATE_MMCR(r13)
std r5, HSTATE_MMCR + 8(r13)
std r6, HSTATE_MMCR + 16(r13)
diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
index d595033..a84aafc 100644
--- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S
+++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
@@ -159,24 +159,15 @@ kvmppc_hv_entry:
mflr r0
std r0, HSTATE_VMHANDLER(r13)
- ld r14, VCPU_GPR(r14)(r4)
- ld r15, VCPU_GPR(r15)(r4)
- ld r16, VCPU_GPR(r16)(r4)
- ld r17, VCPU_GPR(r17)(r4)
- ld r18, VCPU_GPR(r18)(r4)
- ld r19, VCPU_GPR(r19)(r4)
- ld r20, VCPU_GPR(r20)(r4)
- ld r21, VCPU_GPR(r21)(r4)
- ld r22, VCPU_GPR(r22)(r4)
- ld r23, VCPU_GPR(r23)(r4)
- ld r24, VCPU_GPR(r24)(r4)
- ld r25, VCPU_GPR(r25)(r4)
- ld r26, VCPU_GPR(r26)(r4)
- ld r27, VCPU_GPR(r27)(r4)
- ld r28, VCPU_GPR(r28)(r4)
- ld r29, VCPU_GPR(r29)(r4)
- ld r30, VCPU_GPR(r30)(r4)
- ld r31, VCPU_GPR(r31)(r4)
+ /* Set partition DABR */
+ /* Do this before re-enabling PMU to avoid P7 DABR corruption bug */
+ li r5,3
+ ld r6,VCPU_DABR(r4)
+ mtspr SPRN_DABRX,r5
+ mtspr SPRN_DABR,r6
+BEGIN_FTR_SECTION
+ isync
+END_FTR_SECTION_IFSET(CPU_FTR_ARCH_206)
/* Load guest PMU registers */
/* R4 is live here (vcpu pointer) */
@@ -215,6 +206,25 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_201)
/* Load up FP, VMX and VSX registers */
bl kvmppc_load_fp
+ ld r14, VCPU_GPR(r14)(r4)
+ ld r15, VCPU_GPR(r15)(r4)
+ ld r16, VCPU_GPR(r16)(r4)
+ ld r17, VCPU_GPR(r17)(r4)
+ ld r18, VCPU_GPR(r18)(r4)
+ ld r19, VCPU_GPR(r19)(r4)
+ ld r20, VCPU_GPR(r20)(r4)
+ ld r21, VCPU_GPR(r21)(r4)
+ ld r22, VCPU_GPR(r22)(r4)
+ ld r23, VCPU_GPR(r23)(r4)
+ ld r24, VCPU_GPR(r24)(r4)
+ ld r25, VCPU_GPR(r25)(r4)
+ ld r26, VCPU_GPR(r26)(r4)
+ ld r27, VCPU_GPR(r27)(r4)
+ ld r28, VCPU_GPR(r28)(r4)
+ ld r29, VCPU_GPR(r29)(r4)
+ ld r30, VCPU_GPR(r30)(r4)
+ ld r31, VCPU_GPR(r31)(r4)
+
BEGIN_FTR_SECTION
/* Switch DSCR to guest value */
ld r5, VCPU_DSCR(r4)
@@ -256,12 +266,6 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_206)
mtspr SPRN_DAR, r5
mtspr SPRN_DSISR, r6
- /* Set partition DABR */
- li r5,3
- ld r6,VCPU_DABR(r4)
- mtspr SPRN_DABRX,r5
- mtspr SPRN_DABR,r6
-
BEGIN_FTR_SECTION
/* Restore AMR and UAMOR, set AMOR to all 1s */
ld r5,VCPU_AMR(r4)
@@ -955,12 +959,6 @@ BEGIN_FTR_SECTION
mtspr SPRN_AMR,r6
END_FTR_SECTION_IFSET(CPU_FTR_ARCH_206)
- /* Restore host DABR and DABRX */
- ld r5,HSTATE_DABR(r13)
- li r6,7
- mtspr SPRN_DABR,r5
- mtspr SPRN_DABRX,r6
-
/* Switch DSCR back to host value */
BEGIN_FTR_SECTION
mfspr r8, SPRN_DSCR
@@ -999,6 +997,10 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_206)
std r5, VCPU_SPRG2(r9)
std r6, VCPU_SPRG3(r9)
+ /* save FP state */
+ mr r3, r9
+ bl .kvmppc_save_fp
+
/* Increment yield count if they have a VPA */
ld r8, VCPU_VPA(r9) /* do they have a VPA? */
cmpdi r8, 0
@@ -1013,6 +1015,12 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_206)
sldi r3, r3, 31 /* MMCR0_FC (freeze counters) bit */
mfspr r4, SPRN_MMCR0 /* save MMCR0 */
mtspr SPRN_MMCR0, r3 /* freeze all counters, disable ints */
+ mfspr r6, SPRN_MMCRA
+BEGIN_FTR_SECTION
+ /* On P7, clear MMCRA in order to disable SDAR updates */
+ li r7, 0
+ mtspr SPRN_MMCRA, r7
+END_FTR_SECTION_IFSET(CPU_FTR_ARCH_206)
isync
beq 21f /* if no VPA, save PMU stuff anyway */
lbz r7, LPPACA_PMCINUSE(r8)
@@ -1021,7 +1029,6 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_206)
std r3, VCPU_MMCR(r9) /* if not, set saved MMCR0 to FC */
b 22f
21: mfspr r5, SPRN_MMCR1
- mfspr r6, SPRN_MMCRA
std r4, VCPU_MMCR(r9)
std r5, VCPU_MMCR + 8(r9)
std r6, VCPU_MMCR + 16(r9)
@@ -1046,17 +1053,20 @@ BEGIN_FTR_SECTION
stw r11, VCPU_PMC + 28(r9)
END_FTR_SECTION_IFSET(CPU_FTR_ARCH_201)
22:
- /* save FP state */
- mr r3, r9
- bl .kvmppc_save_fp
/* Secondary threads go off to take a nap on POWER7 */
BEGIN_FTR_SECTION
- lwz r0,VCPU_PTID(r3)
+ lwz r0,VCPU_PTID(r9)
cmpwi r0,0
bne secondary_nap
END_FTR_SECTION_IFSET(CPU_FTR_ARCH_206)
+ /* Restore host DABR and DABRX */
+ ld r5,HSTATE_DABR(r13)
+ li r6,7
+ mtspr SPRN_DABR,r5
+ mtspr SPRN_DABRX,r6
+
/*
* Reload DEC. HDEC interrupts were disabled when
* we reloaded the host's LPCR value.
@@ -1393,7 +1403,12 @@ bounce_ext_interrupt:
_GLOBAL(kvmppc_h_set_dabr)
std r4,VCPU_DABR(r3)
- mtspr SPRN_DABR,r4
+ /* Work around P7 bug where DABR can get corrupted on mtspr */
+1: mtspr SPRN_DABR,r4
+ mfspr r5, SPRN_DABR
+ cmpd r4, r5
+ bne 1b
+ isync
li r3,0
blr
@@ -1615,8 +1630,8 @@ kvm_no_guest:
* r3 = vcpu pointer
*/
_GLOBAL(kvmppc_save_fp)
- mfmsr r9
- ori r8,r9,MSR_FP
+ mfmsr r5
+ ori r8,r5,MSR_FP
#ifdef CONFIG_ALTIVEC
BEGIN_FTR_SECTION
oris r8,r8,MSR_VEC@h
@@ -1665,7 +1680,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC)
#endif
mfspr r6,SPRN_VRSAVE
stw r6,VCPU_VRSAVE(r3)
- mtmsrd r9
+ mtmsrd r5
isync
blr
--
1.6.0.2
next prev parent reply other threads:[~2012-03-15 12:11 UTC|newest]
Thread overview: 58+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-03-15 12:10 [PULL 00/56] ppc patch queue 2012-03-15 Alexander Graf
2012-03-15 12:10 ` [PATCH 01/56] KVM: PPC: Book3s_32: Fix compile error Alexander Graf
2012-03-15 12:10 ` [PATCH 02/56] powerpc/booke: Set CPU_FTR_DEBUG_LVL_EXC on 32-bit Alexander Graf
2012-03-15 12:10 ` [PATCH 03/56] powerpc/e500: split CPU_FTRS_ALWAYS/CPU_FTRS_POSSIBLE Alexander Graf
2012-03-15 12:10 ` [PATCH 04/56] KVM: PPC: factor out lpid allocator from book3s_64_mmu_hv Alexander Graf
2012-03-15 12:10 ` [PATCH 05/56] KVM: PPC: booke: add booke-level vcpu load/put Alexander Graf
2012-03-15 12:10 ` [PATCH 06/56] KVM: PPC: booke: Move vm core init/destroy out of booke.c Alexander Graf
2012-03-15 12:10 ` [PATCH 07/56] KVM: PPC: e500: rename e500_tlb.h to e500.h Alexander Graf
2012-03-15 12:10 ` [PATCH 08/56] KVM: PPC: e500: merge <asm/kvm_e500.h> into arch/powerpc/kvm/e500.h Alexander Graf
2012-03-15 12:10 ` [PATCH 09/56] KVM: PPC: e500: clean up arch/powerpc/kvm/e500.h Alexander Graf
2012-03-15 12:10 ` [PATCH 10/56] KVM: PPC: e500: refactor core-specific TLB code Alexander Graf
2012-03-15 12:10 ` [PATCH 11/56] KVM: PPC: e500: Track TLB1 entries with a bitmap Alexander Graf
2012-03-15 12:10 ` [PATCH 12/56] KVM: PPC: e500: emulate tlbilx Alexander Graf
2012-03-15 12:10 ` [PATCH 13/56] powerpc/booke: Provide exception macros with interrupt name Alexander Graf
2012-03-15 12:10 ` [PATCH 14/56] KVM: PPC: booke: category E.HV (GS-mode) support Alexander Graf
2012-03-15 12:10 ` [PATCH 15/56] KVM: PPC: booke: standard PPC floating point support Alexander Graf
2012-03-15 12:10 ` [PATCH 16/56] KVM: PPC: e500mc support Alexander Graf
2012-03-15 12:10 ` [PATCH 17/56] KVM: PPC: e500mc: Add doorbell emulation support Alexander Graf
2012-03-15 12:10 ` [PATCH 18/56] KVM: PPC: e500mc: implicitly set MSR_GS Alexander Graf
2012-03-15 12:10 ` [PATCH 19/56] KVM: PPC: e500mc: Move r1/r2 restoration very early Alexander Graf
2012-03-15 12:10 ` [PATCH 20/56] KVM: PPC: e500mc: add load inst fixup Alexander Graf
2012-03-15 12:10 ` [PATCH 21/56] KVM: PPC: rename CONFIG_KVM_E500 -> CONFIG_KVM_E500V2 Alexander Graf
2012-03-15 12:10 ` [PATCH 22/56] KVM: PPC: make e500v2 kvm and e500mc cpu mutually exclusive Alexander Graf
2012-03-15 12:10 ` [PATCH 23/56] KVM: PPC: booke: remove leftover debugging Alexander Graf
2012-03-15 12:10 ` [PATCH 24/56] KVM: PPC: booke: deliver program int on emulation failure Alexander Graf
2012-03-15 12:10 ` [PATCH 25/56] KVM: PPC: booke: rework rescheduling checks Alexander Graf
2012-03-15 12:10 ` [PATCH 26/56] KVM: PPC: booke: BOOKE_IRQPRIO_MAX is n+1 Alexander Graf
2012-03-15 12:10 ` [PATCH 27/56] KVM: PPC: bookehv: fix exit timing Alexander Graf
2012-03-15 12:10 ` [PATCH 28/56] KVM: PPC: bookehv: remove negation for CONFIG_64BIT Alexander Graf
2012-03-15 12:10 ` [PATCH 29/56] KVM: PPC: bookehv: remove SET_VCPU Alexander Graf
2012-03-15 12:10 ` [PATCH 30/56] KVM: PPC: bookehv: disable MAS register updates early Alexander Graf
2012-03-15 12:11 ` [PATCH 31/56] KVM: PPC: bookehv: add comment about shadow_msr Alexander Graf
2012-03-15 12:11 ` [PATCH 32/56] KVM: PPC: booke: Readd debug abort code for machine check Alexander Graf
2012-03-15 12:11 ` [PATCH 33/56] KVM: PPC: booke: add GS documentation for program interrupt Alexander Graf
2012-03-15 12:11 ` [PATCH 34/56] KVM: PPC: bookehv: remove unused code Alexander Graf
2012-03-15 12:11 ` [PATCH 35/56] KVM: PPC: e500: fix typo in tlb code Alexander Graf
2012-03-15 12:11 ` [PATCH 36/56] KVM: PPC: booke: Support perfmon interrupts Alexander Graf
2012-03-15 12:11 ` [PATCH 37/56] KVM: PPC: booke: expose good state on irq reinject Alexander Graf
2012-03-15 12:11 ` [PATCH 38/56] KVM: PPC: booke: Reinject performance monitor interrupts Alexander Graf
2012-03-15 12:11 ` [PATCH 39/56] KVM: PPC: Booke: only prepare to enter when we enter Alexander Graf
2012-03-15 12:11 ` [PATCH 40/56] KVM: PPC: Book3s: PR: Add SPAPR H_BULK_REMOVE support Alexander Graf
2012-03-15 12:11 ` [PATCH 41/56] KVM: PPC: Book3S HV: Fix kvm_alloc_linear in case where no linears exist Alexander Graf
2012-03-15 12:11 ` [PATCH 42/56] KVM: PPC: Book3S HV: Save and restore CR in __kvmppc_vcore_entry Alexander Graf
2012-03-15 12:11 ` [PATCH 43/56] KVM: PPC: Save/Restore CR over vcpu_run Alexander Graf
2012-03-15 12:11 ` [PATCH 44/56] KVM: PPC: Book3S HV: Make secondary threads more robust against stray IPIs Alexander Graf
2012-03-15 12:11 ` [PATCH 45/56] KVM: PPC: Book3S HV: Make virtual processor area registration more robust Alexander Graf
2012-03-15 12:11 ` [PATCH 46/56] KVM: PPC: Book3S HV: Report stolen time to guest through dispatch trace log Alexander Graf
2012-03-15 12:11 ` [PATCH 47/56] Restore guest CR after exit timing calculation Alexander Graf
2012-03-15 12:11 ` [PATCH 48/56] KVM: PPC: Book 3S: Fix compilation for !HV configs Alexander Graf
2012-03-15 12:11 ` Alexander Graf [this message]
2012-03-15 12:11 ` [PATCH 50/56] KVM: PPC: Pass EA to updating emulation ops Alexander Graf
2012-03-15 12:11 ` [PATCH 51/56] KVM: PPC: Book3S: Compile fix for ppc32 in HIOR Alexander Graf
2012-03-15 12:11 ` [PATCH 52/56] KVM: PPC: Emulate tw and td instructions Alexander Graf
2012-03-15 12:11 ` [PATCH 53/56] KVM: PPC: Book3s: PR: Add HV traps so we can run in HV=1 mode on p7 Alexander Graf
2012-03-15 12:11 ` [PATCH 54/56] KVM: PPC: Book3S: PR: Fix preemption Alexander Graf
2012-03-15 12:11 ` [PATCH 55/56] KVM: PPC: Ignore unhalt request from kvm_vcpu_block Alexander Graf
2012-03-15 12:11 ` [PATCH 56/56] powerpc/kvm: Fix magic page vs. 32-bit RTAS on ppc64 Alexander Graf
2012-03-20 14:47 ` [PULL 00/56] ppc patch queue 2012-03-15 Avi Kivity
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