Re: [PATCH v3 08/10] KVM: s390: Free the mmu cache when kvm_arch_vcpu_create() fails

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Low] Mixing goto-based error handling with scope-based cleanup (__free) in the same function.
--

--- Patch [8]: [PATCH v3 08/10] KVM: s390: Free the mmu cache when kvm_arch_vcpu_create() fails ---
commit f957b5e2634eaa5f53bf929349c916ffa15d9f2c
Author: Claudio Imbrenda <imbrenda@linux.ibm.com>

KVM: s390: Free the mmu cache when kvm_arch_vcpu_create() fails

This commit switches kvm_arch_vcpu_create() to use the __free() 
scope-based cleanup helper for the mmu cache to prevent memory leaks 
during initialization failures.

> diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
> --- a/arch/s390/kvm/kvm-s390.c
> +++ b/arch/s390/kvm/kvm-s390.c
> @@ -3794,19 +3794,17 @@ int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id)
>  
>  int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
>  {
> +	struct kvm_s390_mmu_cache *mc __free(kvm_s390_mmu_cache) = NULL;
>  	struct sie_page *sie_page;
>  	int rc;

[ ... ]

> @@ -3862,6 +3860,8 @@ int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
>  	if (rc)
>  		goto out_ucontrol_uninit;
>  

[Severity: Low]
Are we permitted to mix scope-based cleanup and goto-based error handling 
in the same function?

The cleanup guidelines indicate that for a given routine, we should generally 
convert all resources that need a goto cleanup to scope-based cleanup, or 
convert none of them. Mixing __free() with existing goto paths can create 
confusing ownership semantics during future refactoring.

Could we either convert out_ucontrol_uninit and out_free_sie_block to use
scope-based cleanup as well, or stick to traditional goto labels for freeing 
the mmu cache?

> +	vcpu->arch.mc = mc;
> +	mc = NULL;
>  	kvm_s390_update_topology_change_report(vcpu->kvm, 1);
>  	return 0;
>

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260727150254.236021-1-imbrenda@linux.ibm.com?part=8