Re: [PATCH v6 3/5] KVM: PPC: clean up redundant kvm_run parameters in assembly
From: Paolo Bonzini <pbonzini@redhat.com>
Date: 2020-07-10 07:57:11
Also in:
kvm, kvmarm, linux-arm-kernel, linux-mips, linux-s390, lkml
On 23/06/20 15:14, Tianjia Zhang wrote:
quoted hunk ↗ jump to hunk
/* Load non-volatile guest state from the vcpu */ - VCPU_LOAD_NVGPRS(r4) + VCPU_LOAD_NVGPRS(r3) kvm_start_lightweight: /* Copy registers into shadow vcpu so we can access them in real mode */ - mr r3, r4 bl FUNC(kvmppc_copy_to_svcpu) nop - REST_GPR(4, r1) + REST_GPR(3, r1) #ifdef CONFIG_PPC_BOOK3S_64 /* Get the dcbz32 flag */@@ -146,7 +144,7 @@ after_sprg3_load:
Below, there are a bunch of references to r3 and r4 left
rldicl r3, r3, 0, 63 /* r3 &= 1 */
stb r3, HSTATE_RESTORE_HID5(r13)
/* Load up guest SPRG3 value, since it's user readable */
lwz r3, VCPU_SHAREDBE(r4) <<<
cmpwi r3, 0
ld r5, VCPU_SHARED(r4) <<<
where r3 is also destroyed. So I'd rather have three patches:
- one that is as small as possible, changing the prototypes and adding
mr r4, r3
- one that entirely swaps out r3 and r4. This would be the hard one to
review!
- one that cleans up the prologue and epilogue
But overall I think it's simplest to just leave out this patch.
Paolo