[v2] LoongArch: KVM: Do not flush tlb if HW PTW supported

[PATCH v2 0/2] LoongArch: KVM: Do not flush tlb if HW PTW supported

Posted by Bibo Mao 9 months, 2 weeks ago

With HW PTW supported, stale TLB is not added if page fault happens. With
EXCCODE_TLBM exception, stale TLB may exist because last read access, tlb
flush operation is necessary with EXCCODE_TLBM exception, and not necessary
with other memory page fault exceptions.

With SW PTW supported, invalid TLB is added in TLB refill exception.
TLB flush operation is necessary with all page fault exceptions.

---
  v1 ... v2:
    1. Add kernel doc notation since new parameter ecode is added, which is
       reported from LKP.
---

Bibo Mao (2):
  LoongArch: KVM: Add parameter exception code with exception handler
  LoongArch: KVM: Do not flush tlb if HW PTW supported

 arch/loongarch/include/asm/kvm_host.h |  2 +-
 arch/loongarch/include/asm/kvm_vcpu.h |  2 +-
 arch/loongarch/kvm/exit.c             | 37 ++++++++++++++-------------
 arch/loongarch/kvm/mmu.c              | 18 ++++++++++---
 4 files changed, 35 insertions(+), 24 deletions(-)


base-commit: 5bc1018675ec28a8a60d83b378d8c3991faa5a27
-- 
2.39.3

Re: [PATCH v2 0/2] LoongArch: KVM: Do not flush tlb if HW PTW supported

Posted by Huacai Chen 8 months, 3 weeks ago

Applied, thanks.

Huacai

On Sun, Apr 27, 2025 at 10:45 AM Bibo Mao <maobibo@loongson.cn> wrote:
>
> With HW PTW supported, stale TLB is not added if page fault happens. With
> EXCCODE_TLBM exception, stale TLB may exist because last read access, tlb
> flush operation is necessary with EXCCODE_TLBM exception, and not necessary
> with other memory page fault exceptions.
>
> With SW PTW supported, invalid TLB is added in TLB refill exception.
> TLB flush operation is necessary with all page fault exceptions.
>
> ---
>   v1 ... v2:
>     1. Add kernel doc notation since new parameter ecode is added, which is
>        reported from LKP.
> ---
>
> Bibo Mao (2):
>   LoongArch: KVM: Add parameter exception code with exception handler
>   LoongArch: KVM: Do not flush tlb if HW PTW supported
>
>  arch/loongarch/include/asm/kvm_host.h |  2 +-
>  arch/loongarch/include/asm/kvm_vcpu.h |  2 +-
>  arch/loongarch/kvm/exit.c             | 37 ++++++++++++++-------------
>  arch/loongarch/kvm/mmu.c              | 18 ++++++++++---
>  4 files changed, 35 insertions(+), 24 deletions(-)
>
>
> base-commit: 5bc1018675ec28a8a60d83b378d8c3991faa5a27
> --
> 2.39.3
>