Merge branch 'kvm-ppc-next' of git://github.com/agraf/linux-2.6 into kvm-queue

[~andy/linux] / arch / powerpc / kvm / book3s_hv_rmhandlers.S

diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
index dfa144cb199bb408d7df7b10d481383f924b3a44..e66d4ec04d953a78a314b43a3a07f47ca27f5ae7 100644 (file)
--- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S
+++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
@@ -160,7 +160,6 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_206)
 
 13:    b       machine_check_fwnmi
 
-
 kvmppc_primary_no_guest:
        /* We handle this much like a ceded vcpu */
        /* set our bit in napping_threads */
@@ -278,12 +277,16 @@ kvm_start_guest:
        /* Clear our vcpu pointer so we don't come back in early */
        li      r0, 0
        std     r0, HSTATE_KVM_VCPU(r13)
+       /*
+        * Make sure we clear HSTATE_KVM_VCPU(r13) before incrementing
+        * the nap_count, because once the increment to nap_count is
+        * visible we could be given another vcpu.
+        */
        lwsync
 
        /* increment the nap count and then go to nap mode */
        ld      r4, HSTATE_KVM_VCORE(r13)
        addi    r4, r4, VCORE_NAP_COUNT
-       lwsync                          /* make previous updates visible */
 51:    lwarx   r3, 0, r4
        addi    r3, r3, 1
        stwcx.  r3, 0, r4
@@ -889,15 +892,14 @@ kvmppc_interrupt_hv:
         * guest CR, R12 saved in shadow VCPU SCRATCH1/0
         * guest R13 saved in SPRN_SCRATCH0
         */
-       /* abuse host_r2 as third scratch area; we get r2 from PACATOC(r13) */
-       std     r9, HSTATE_HOST_R2(r13)
+       std     r9, HSTATE_SCRATCH2(r13)
 
        lbz     r9, HSTATE_IN_GUEST(r13)
        cmpwi   r9, KVM_GUEST_MODE_HOST_HV
        beq     kvmppc_bad_host_intr
 #ifdef CONFIG_KVM_BOOK3S_PR_POSSIBLE
        cmpwi   r9, KVM_GUEST_MODE_GUEST
-       ld      r9, HSTATE_HOST_R2(r13)
+       ld      r9, HSTATE_SCRATCH2(r13)
        beq     kvmppc_interrupt_pr
 #endif
        /* We're now back in the host but in guest MMU context */
@@ -917,7 +919,7 @@ kvmppc_interrupt_hv:
        std     r6, VCPU_GPR(R6)(r9)
        std     r7, VCPU_GPR(R7)(r9)
        std     r8, VCPU_GPR(R8)(r9)
-       ld      r0, HSTATE_HOST_R2(r13)
+       ld      r0, HSTATE_SCRATCH2(r13)
        std     r0, VCPU_GPR(R9)(r9)
        std     r10, VCPU_GPR(R10)(r9)
        std     r11, VCPU_GPR(R11)(r9)
@@ -1289,14 +1291,13 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_201)
         */
        /* Increment the threads-exiting-guest count in the 0xff00
           bits of vcore->entry_exit_count */
-       lwsync
        ld      r5,HSTATE_KVM_VCORE(r13)
        addi    r6,r5,VCORE_ENTRY_EXIT
 41:    lwarx   r3,0,r6
        addi    r0,r3,0x100
        stwcx.  r0,0,r6
        bne     41b
-       lwsync
+       isync           /* order stwcx. vs. reading napping_threads */
 
        /*
         * At this point we have an interrupt that we have to pass
@@ -1327,6 +1328,8 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_201)
        sld     r0,r0,r4
        andc.   r3,r3,r0                /* no sense IPI'ing ourselves */
        beq     43f
+       /* Order entry/exit update vs. IPIs */
+       sync
        mulli   r4,r4,PACA_SIZE         /* get paca for thread 0 */
        subf    r6,r4,r13
 42:    andi.   r0,r3,1
@@ -1914,10 +1917,10 @@ END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_206)
        bge     kvm_cede_exit
        stwcx.  r4,0,r6
        bne     31b
+       /* order napping_threads update vs testing entry_exit_count */
+       isync
        li      r0,NAPPING_CEDE
        stb     r0,HSTATE_NAPPING(r13)
-       /* order napping_threads update vs testing entry_exit_count */
-       lwsync
        lwz     r7,VCORE_ENTRY_EXIT(r5)
        cmpwi   r7,0x100
        bge     33f             /* another thread already exiting */