Re: [RFC 3/5] powerpc: kvm: drop 32-bit book3s

["Arnd Bergmann" <arnd@arndb.de>]

On Thu, Dec 12, 2024, at 19:34, Christophe Leroy wrote:
> Le 12/12/2024 à 13:55, Arnd Bergmann a écrit :
>
> $ git grep KVM_BOOK3S_32_HANDLER
> arch/powerpc/include/asm/processor.h:#ifdef CONFIG_KVM_BOOK3S_32_HANDLER
> arch/powerpc/include/asm/processor.h:#endif /* 
> CONFIG_KVM_BOOK3S_32_HANDLER */
> arch/powerpc/kernel/asm-offsets.c:#ifdef CONFIG_KVM_BOOK3S_32_HANDLER

Fixed now.

> What about the following in asm-offsets.c, should it still test 
> CONFIG_PPC_BOOK3S_64 ? Is CONFIG_KVM_BOOK3S_PR_POSSIBLE still possible 
> on something else ?
>
> #if defined(CONFIG_PPC_BOOK3S_64) && defined(CONFIG_KVM_BOOK3S_PR_POSSIBLE)
> 	OFFSET(VCPU_SHAREDBE, kvm_vcpu, arch.shared_big_endian);
> #endif
>
> Shouldn't CONFIG_KVM and/or CONFIG_VIRTUALISATION be restricted to 
> CONFIG_PPC64 now ?

Agreed, fixed and found one more in that file.

> What about:
>
> arch/powerpc/kernel/head_book3s_32.S:#include <asm/kvm_book3s_asm.h>
> arch/powerpc/kernel/head_book3s_32.S:#include "../kvm/book3s_rmhandlers.S"

Removed.

> There is still arch/powerpc/kvm/book3s_32_mmu.c

This one is used for 32-bit guests and needs to stay I think.

See below for the changes I've now folded into this patch.

     Arnd

diff --git a/arch/powerpc/include/asm/kvm_book3s.h b/arch/powerpc/include/asm/kvm_book3s.h
index 71532e0e65a6..7e13e48dbc6b 100644
--- a/arch/powerpc/include/asm/kvm_book3s.h
+++ b/arch/powerpc/include/asm/kvm_book3s.h
@@ -377,7 +377,9 @@ static inline struct kvmppc_vcpu_book3s *to_book3s(struct kvm_vcpu *vcpu)
 
 /* Also add subarch specific defines */
 
+#ifdef CONFIG_KVM_BOOK3S_64_HANDLER
 #include <asm/kvm_book3s_64.h>
+#endif
 
 static inline void kvmppc_set_gpr(struct kvm_vcpu *vcpu, int num, ulong val)
 {
diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h
index 6e1108f8fce6..56b01a135fcb 100644
--- a/arch/powerpc/include/asm/kvm_host.h
+++ b/arch/powerpc/include/asm/kvm_host.h
@@ -793,7 +793,7 @@ struct kvm_vcpu_arch {
 	struct machine_check_event mce_evt; /* Valid if trap == 0x200 */
 
 	struct kvm_vcpu_arch_shared *shared;
-#if defined(CONFIG_PPC_BOOK3S_64) && defined(CONFIG_KVM_BOOK3S_PR_POSSIBLE)
+#ifdef CONFIG_KVM_BOOK3S_PR_POSSIBLE
 	bool shared_big_endian;
 #endif
 	unsigned long magic_page_pa; /* phys addr to map the magic page to */
diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h
index ca3829d47ab7..001cd00d18f0 100644
--- a/arch/powerpc/include/asm/kvm_ppc.h
+++ b/arch/powerpc/include/asm/kvm_ppc.h
@@ -951,7 +951,7 @@ static inline void kvmppc_mmu_flush_icache(kvm_pfn_t pfn)
  */
 static inline bool kvmppc_shared_big_endian(struct kvm_vcpu *vcpu)
 {
-#if defined(CONFIG_PPC_BOOK3S_64) && defined(CONFIG_KVM_BOOK3S_PR_POSSIBLE)
+#if defined(CONFIG_KVM_BOOK3S_PR_POSSIBLE)
 	/* Only Book3S_64 PR supports bi-endian for now */
 	return vcpu->arch.shared_big_endian;
 #elif defined(CONFIG_PPC_BOOK3S_64) && defined(__LITTLE_ENDIAN__)
diff --git a/arch/powerpc/include/asm/processor.h b/arch/powerpc/include/asm/processor.h
index 6b94de17201c..d77092554788 100644
--- a/arch/powerpc/include/asm/processor.h
+++ b/arch/powerpc/include/asm/processor.h
@@ -223,9 +223,6 @@ struct thread_struct {
 	struct thread_vr_state ckvr_state; /* Checkpointed VR state */
 	unsigned long	ckvrsave; /* Checkpointed VRSAVE */
 #endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
-#ifdef CONFIG_KVM_BOOK3S_32_HANDLER
-	void*		kvm_shadow_vcpu; /* KVM internal data */
-#endif /* CONFIG_KVM_BOOK3S_32_HANDLER */
 #if defined(CONFIG_KVM) && defined(CONFIG_BOOKE)
 	struct kvm_vcpu	*kvm_vcpu;
 #endif
diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c
index 7a390bd4f4af..c4186061694c 100644
--- a/arch/powerpc/kernel/asm-offsets.c
+++ b/arch/powerpc/kernel/asm-offsets.c
@@ -147,9 +147,6 @@ int main(void)
 	OFFSET(THREAD_USED_SPE, thread_struct, used_spe);
 #endif /* CONFIG_SPE */
 #endif /* CONFIG_PPC64 */
-#ifdef CONFIG_KVM_BOOK3S_32_HANDLER
-	OFFSET(THREAD_KVM_SVCPU, thread_struct, kvm_shadow_vcpu);
-#endif
 #if defined(CONFIG_KVM) && defined(CONFIG_BOOKE)
 	OFFSET(THREAD_KVM_VCPU, thread_struct, kvm_vcpu);
 #endif
@@ -401,7 +398,7 @@ int main(void)
 	OFFSET(VCPU_SHARED, kvm_vcpu, arch.shared);
 	OFFSET(VCPU_SHARED_MSR, kvm_vcpu_arch_shared, msr);
 	OFFSET(VCPU_SHADOW_MSR, kvm_vcpu, arch.shadow_msr);
-#if defined(CONFIG_PPC_BOOK3S_64) && defined(CONFIG_KVM_BOOK3S_PR_POSSIBLE)
+#ifdef CONFIG_KVM_BOOK3S_PR_POSSIBLE
 	OFFSET(VCPU_SHAREDBE, kvm_vcpu, arch.shared_big_endian);
 #endif
 
@@ -511,19 +508,13 @@ int main(void)
 	OFFSET(VCPU_TAR_TM, kvm_vcpu, arch.tar_tm);
 #endif
 
-#ifdef CONFIG_PPC_BOOK3S_64
 #ifdef CONFIG_KVM_BOOK3S_PR_POSSIBLE
 	OFFSET(PACA_SVCPU, paca_struct, shadow_vcpu);
 # define SVCPU_FIELD(x, f)	DEFINE(x, offsetof(struct paca_struct, shadow_vcpu.f))
 #else
 # define SVCPU_FIELD(x, f)
 #endif
-# define HSTATE_FIELD(x, f)	DEFINE(x, offsetof(struct paca_struct, kvm_hstate.f))
-#else	/* 32-bit */
-# define SVCPU_FIELD(x, f)	DEFINE(x, offsetof(struct kvmppc_book3s_shadow_vcpu, f))
-# define HSTATE_FIELD(x, f)	DEFINE(x, offsetof(struct kvmppc_book3s_shadow_vcpu, hstate.f))
-#endif
-
+#define HSTATE_FIELD(x, f)	DEFINE(x, offsetof(struct paca_struct, kvm_hstate.f))
 	SVCPU_FIELD(SVCPU_CR, cr);
 	SVCPU_FIELD(SVCPU_XER, xer);
 	SVCPU_FIELD(SVCPU_CTR, ctr);
@@ -547,14 +538,9 @@ int main(void)
 	SVCPU_FIELD(SVCPU_FAULT_DAR, fault_dar);
 	SVCPU_FIELD(SVCPU_LAST_INST, last_inst);
 	SVCPU_FIELD(SVCPU_SHADOW_SRR1, shadow_srr1);
-#ifdef CONFIG_PPC_BOOK3S_32
-	SVCPU_FIELD(SVCPU_SR, sr);
-#endif
-#ifdef CONFIG_PPC64
 	SVCPU_FIELD(SVCPU_SLB, slb);
 	SVCPU_FIELD(SVCPU_SLB_MAX, slb_max);
 	SVCPU_FIELD(SVCPU_SHADOW_FSCR, shadow_fscr);
-#endif
 
 	HSTATE_FIELD(HSTATE_HOST_R1, host_r1);
 	HSTATE_FIELD(HSTATE_HOST_R2, host_r2);
@@ -601,12 +587,9 @@ int main(void)
 	OFFSET(KVM_SPLIT_NAPPED, kvm_split_mode, napped);
 #endif /* CONFIG_KVM_BOOK3S_HV_POSSIBLE */
 
-#ifdef CONFIG_PPC_BOOK3S_64
 	HSTATE_FIELD(HSTATE_CFAR, cfar);
 	HSTATE_FIELD(HSTATE_PPR, ppr);
 	HSTATE_FIELD(HSTATE_HOST_FSCR, host_fscr);
-#endif /* CONFIG_PPC_BOOK3S_64 */
-
 #else /* CONFIG_PPC_BOOK3S */
 	OFFSET(VCPU_CR, kvm_vcpu, arch.regs.ccr);
 	OFFSET(VCPU_XER, kvm_vcpu, arch.regs.xer);
diff --git a/arch/powerpc/kernel/head_32.h b/arch/powerpc/kernel/head_32.h
index 9cba7dbf58dd..24e89dadc74d 100644
--- a/arch/powerpc/kernel/head_32.h
+++ b/arch/powerpc/kernel/head_32.h
@@ -172,7 +172,6 @@ _ASM_NOKPROBE_SYMBOL(\name\()_virt)
 #define	START_EXCEPTION(n, label)		\
 	__HEAD;					\
 	. = n;					\
-	DO_KVM n;				\
 label:
 
 #else
diff --git a/arch/powerpc/kernel/head_book3s_32.S b/arch/powerpc/kernel/head_book3s_32.S
index cb2bca76be53..505d0009ddc9 100644
--- a/arch/powerpc/kernel/head_book3s_32.S
+++ b/arch/powerpc/kernel/head_book3s_32.S
@@ -30,7 +30,6 @@
 #include <asm/asm-offsets.h>
 #include <asm/ptrace.h>
 #include <asm/bug.h>
-#include <asm/kvm_book3s_asm.h>
 #include <asm/feature-fixups.h>
 #include <asm/interrupt.h>
 
@@ -861,10 +860,6 @@ END_MMU_FTR_SECTION_IFCLR(MMU_FTR_HPTE_TABLE)
 	rfi
 #endif /* CONFIG_SMP */
 
-#ifdef CONFIG_KVM_BOOK3S_HANDLER
-#include "../kvm/book3s_rmhandlers.S"
-#endif
-
 /*
  * Load stuff into the MMU.  Intended to be called with
  * IR=0 and DR=0.