Re: [PATCH] KVM: PPC: Book3S HV: Workaround high stack usage with clang

From: Michael Ellerman
Date: Thu Jun 24 2021 - 09:59:56 EST


On Mon, 21 Jun 2021 11:24:40 -0700, Nathan Chancellor wrote:
> LLVM does not emit optimal byteswap assembly, which results in high
> stack usage in kvmhv_enter_nested_guest() due to the inlining of
> byteswap_pt_regs(). With LLVM 12.0.0:
>
> arch/powerpc/kvm/book3s_hv_nested.c:289:6: error: stack frame size of
> 2512 bytes in function 'kvmhv_enter_nested_guest' [-Werror,-Wframe-larger-than=]
> long kvmhv_enter_nested_guest(struct kvm_vcpu *vcpu)
> ^
> 1 error generated.
>
> [...]

Applied to powerpc/topic/ppc-kvm.

[1/1] KVM: PPC: Book3S HV: Workaround high stack usage with clang
https://git.kernel.org/powerpc/c/51696f39cbee5bb684e7959c0c98b5f54548aa34

cheers