linux-kernel - Re: [RFC PATCH] KVM: x86: Dynamically allocate bitmap to fix -Wframe-larger-than error

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Message-ID: <175079250757.516293.17591190576479567167.b4-ty@google.com>
Date: Tue, 24 Jun 2025 12:36:26 -0700
From: Sean Christopherson <seanjc@...gle.com>
To: Sean Christopherson <seanjc@...gle.com>, kvm@...r.kernel.org, 
	avinashlalotra <abinashlalotra@...il.com>
Cc: linux-kernel@...r.kernel.org, vkuznets@...hat.com, pbonzini@...hat.com, 
	tglx@...utronix.de, mingo@...hat.com, bp@...en8.de, 
	dave.hansen@...ux.intel.com, x86@...nel.org, hpa@...or.com, 
	avinashlalotra <abinashsinghlalotra@...il.com>
Subject: Re: [RFC PATCH] KVM: x86: Dynamically allocate bitmap to fix
 -Wframe-larger-than error

On Fri, Jun 13, 2025, Sean Christopherson wrote:                                
> Use a preallocated per-vCPU bitmap for tracking the unpacked set of vCPUs     
> being targeted for Hyper-V's paravirt TLB flushing.  If KVM_MAX_NR_VCPUS      
> is set to 4096 (which is allowed even for MAXSMP=n builds), putting the       
> vCPU mask on-stack pushes kvm_hv_flush_tlb() past the default FRAME_WARN      
> limit.
> 
> [...]

Applied my version to kvm-x86 fixes, thanks!

[1/1] KVM: x86/hyper-v: Use preallocated per-vCPU buffer for de-sparsified vCPU masks
      https://github.com/kvm-x86/linux/commit/4bbcc07a56e6

--
https://github.com/kvm-x86/kvm-unit-tests/tree/next