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From: Nicholas Piggin <npiggin@gmail.com>
To: kvm-ppc@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org, Nicholas Piggin <npiggin@gmail.com>
Subject: [PATCH 02/13] powerpc/64s: remove KVM SKIP test from instruction breakpoint handler
Date: Fri, 19 Feb 2021 16:35:31 +1000	[thread overview]
Message-ID: <20210219063542.1425130-3-npiggin@gmail.com> (raw)
In-Reply-To: <20210219063542.1425130-1-npiggin@gmail.com>

The code being executed in KVM_GUEST_MODE_SKIP is hypervisor code with
MSR[IR]=0, so the faults of concern are the d-side ones caused by access
to guest context by the hypervisor.

Instruction breakpoint interrupts are not a concern here. It's unlikely
any good would come of causing breaks in this code, but skipping the
instruction that caused it won't help matters (e.g., skip the mtmsr that
sets MSR[DR]=0 or clears KVM_GUEST_MODE_SKIP).

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
 arch/powerpc/kernel/exceptions-64s.S | 1 -
 1 file changed, 1 deletion(-)

diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S
index 5d0ad3b38e90..5bc689a546ae 100644
--- a/arch/powerpc/kernel/exceptions-64s.S
+++ b/arch/powerpc/kernel/exceptions-64s.S
@@ -2597,7 +2597,6 @@ EXC_VIRT_NONE(0x5200, 0x100)
 INT_DEFINE_BEGIN(instruction_breakpoint)
 	IVEC=0x1300
 #ifdef CONFIG_KVM_BOOK3S_PR_POSSIBLE
-	IKVM_SKIP=1
 	IKVM_REAL=1
 #endif
 INT_DEFINE_END(instruction_breakpoint)
-- 
2.23.0


  parent reply	other threads:[~2021-02-19  6:37 UTC|newest]

Thread overview: 20+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-02-19  6:35 [PATCH 00/13] KVM: PPC: Book3S: C-ify the P9 entry/exit code Nicholas Piggin
2021-02-19  6:35 ` [PATCH 01/13] powerpc/64s: Remove KVM handler support from CBE_RAS interrupts Nicholas Piggin
2021-02-22 22:22   ` Fabiano Rosas
2021-02-19  6:35 ` Nicholas Piggin [this message]
2021-02-22 22:22   ` [PATCH 02/13] powerpc/64s: remove KVM SKIP test from instruction breakpoint handler Fabiano Rosas
2021-02-19  6:35 ` [PATCH 03/13] KVM: PPC: Book3S HV: Ensure MSR[ME] is always set in guest MSR Nicholas Piggin
2021-02-22 22:23   ` Fabiano Rosas
2021-02-19  6:35 ` [PATCH 04/13] KVM: PPC: Book3S 64: remove unused kvmppc_h_protect argument Nicholas Piggin
2021-02-19  6:35 ` [PATCH 05/13] KVM: PPC: Book3S 64: move KVM interrupt entry to a common entry point Nicholas Piggin
2021-02-19  6:35 ` [PATCH 06/13] KVM: PPC: Book3S 64: Move GUEST_MODE_SKIP test into KVM Nicholas Piggin
2021-02-22 22:40   ` Fabiano Rosas
2021-02-19  6:35 ` [PATCH 07/13] KVM: PPC: Book3S 64: add hcall interrupt handler Nicholas Piggin
2021-02-19  6:35 ` [PATCH 08/13] KVM: PPC: Book3S HV: Move hcall early register setup to KVM Nicholas Piggin
2021-02-19  6:35 ` [PATCH 09/13] KVM: PPC: Book3S HV: Move interrupt " Nicholas Piggin
2021-02-19  6:35 ` [PATCH 10/13] KVM: PPC: Book3S HV: move bad_host_intr check to HV handler Nicholas Piggin
2021-02-19  6:35 ` [PATCH 11/13] KVM: PPC: Book3S HV: Minimise hcall handler calling convention differences Nicholas Piggin
2021-02-19  6:35 ` [PATCH 12/13] KVM: PPC: Book3S HV: Move radix MMU switching together in the P9 path Nicholas Piggin
2021-02-24 20:36   ` Fabiano Rosas
2021-02-25 10:59     ` Nicholas Piggin
2021-02-19  6:35 ` [PATCH 13/13] KVM: PPC: Book3S HV: Implement the rest of the P9 entry/exit handling in C Nicholas Piggin

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