KVM: PPC: Book3E: Fix CONFIG_TRACE_IRQFLAGS support

32-bit does not trace_irqs_off() to match the trace_irqs_on() call in
kvmppc_fix_ee_before_entry(). This can lead to irqs being enabled twice
in the trace, and the irqs-off region between guest exit and the host
enabling local irqs again is not properly traced.

64-bit code does call this, but from asm code where volatiles are live
and so incorrectly get clobbered.

Move the irq reconcile into C to fix both problems.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20221127124942.1665522-2-npiggin@gmail.com

diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h
index bfacf12..eae9619 100644 (file)
--- a/arch/powerpc/include/asm/kvm_ppc.h
+++ b/arch/powerpc/include/asm/kvm_ppc.h
@@ -1014,6 +1014,18 @@ static inline void kvmppc_fix_ee_before_entry(void)
 #endif
 }
 
+static inline void kvmppc_fix_ee_after_exit(void)
+{
+#ifdef CONFIG_PPC64
+       /* Only need to enable IRQs by hard enabling them after this */
+       local_paca->irq_happened = PACA_IRQ_HARD_DIS;
+       irq_soft_mask_set(IRQS_ALL_DISABLED);
+#endif
+
+       trace_hardirqs_off();
+}
+
+
 static inline ulong kvmppc_get_ea_indexed(struct kvm_vcpu *vcpu, int ra, int rb)
 {
        ulong ea;

diff --git a/arch/powerpc/kvm/booke.c b/arch/powerpc/kvm/booke.c
index 7b4920e..0dce93c 100644 (file)
--- a/arch/powerpc/kvm/booke.c
+++ b/arch/powerpc/kvm/booke.c
@@ -1015,6 +1015,9 @@ int kvmppc_handle_exit(struct kvm_vcpu *vcpu, unsigned int exit_nr)
        u32 last_inst = KVM_INST_FETCH_FAILED;
        enum emulation_result emulated = EMULATE_DONE;
 
+       /* Fix irq state (pairs with kvmppc_fix_ee_before_entry()) */
+       kvmppc_fix_ee_after_exit();
+
        /* update before a new last_exit_type is rewritten */
        kvmppc_update_timing_stats(vcpu);
 

diff --git a/arch/powerpc/kvm/bookehv_interrupts.S b/arch/powerpc/kvm/bookehv_interrupts.S
index 8262c14..b5fe6fb 100644 (file)
--- a/arch/powerpc/kvm/bookehv_interrupts.S
+++ b/arch/powerpc/kvm/bookehv_interrupts.S
@@ -424,15 +424,6 @@ _GLOBAL(kvmppc_resume_host)
        mtspr   SPRN_EPCR, r3
        isync
 
-#ifdef CONFIG_64BIT
-       /*
-        * We enter with interrupts disabled in hardware, but
-        * we need to call RECONCILE_IRQ_STATE to ensure
-        * that the software state is kept in sync.
-        */
-       RECONCILE_IRQ_STATE(r3,r5)
-#endif
-
        /* Switch to kernel stack and jump to handler. */
        mr      r3, r4
        mr      r5, r14 /* intno */