From: Sean Christopherson <sean.j.christopherson@intel.com>
To: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-kernel@vger.kernel.org,
"Paolo Bonzini" <pbonzini@redhat.com>,
"Radim Krčmář" <rkrcmar@redhat.com>,
kvm@vger.kernel.org
Subject: Re: [PATCH] kvm: no need to check return value of debugfs_create functions
Date: Tue, 22 Jan 2019 09:21:02 -0800 [thread overview]
Message-ID: <20190122172102.GE28513@linux.intel.com> (raw)
In-Reply-To: <20190122152151.16139-51-gregkh@linuxfoundation.org>
On Tue, Jan 22, 2019 at 04:21:50PM +0100, Greg Kroah-Hartman wrote:
> When calling debugfs functions, there is no need to ever check the
> return value. The function can work or not, but the code logic should
> never do something different based on this.
What about wanting to make the debugfs all-or-nothing? That seems like
a legitimate usage of checking the return value.
E.g. KVM removes the debugfs if kvm_arch_create_vcpu_debugfs() fails, and
the arch/x86/kvm/debugfs.c implementation of kvm_arch_create_vcpu_debugfs()
returns an error if any of its debugfs_create_file() calls fail.
If you're adamant about removing all debugfs create return value checks,
the aforementioned debugfs_create_file() calls should also be removed.
And at that point kvm_create_vcpu_debugfs() should have a 'void' return
value.
>
> Cc: Paolo Bonzini <pbonzini@redhat.com>
> Cc: "Radim Krčmář" <rkrcmar@redhat.com>
> Cc: kvm@vger.kernel.org
> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> ---
> virt/kvm/kvm_main.c | 4 +---
> 1 file changed, 1 insertion(+), 3 deletions(-)
>
> diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
> index 5ecea812cb6a..4f96450ecdfc 100644
> --- a/virt/kvm/kvm_main.c
> +++ b/virt/kvm/kvm_main.c
> @@ -2528,9 +2528,7 @@ static int kvm_create_vcpu_debugfs(struct kvm_vcpu *vcpu)
>
> snprintf(dir_name, sizeof(dir_name), "vcpu%d", vcpu->vcpu_id);
> vcpu->debugfs_dentry = debugfs_create_dir(dir_name,
> - vcpu->kvm->debugfs_dentry);
> - if (!vcpu->debugfs_dentry)
> - return -ENOMEM;
> + vcpu->kvm->debugfs_dentry);
>
> ret = kvm_arch_create_vcpu_debugfs(vcpu);
> if (ret < 0) {
> --
> 2.20.1
>
next prev parent reply other threads:[~2019-01-22 17:21 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-01-22 15:21 [PATCH] kvm: no need to check return value of debugfs_create functions Greg Kroah-Hartman
2019-01-22 17:21 ` Sean Christopherson [this message]
2019-01-22 17:29 ` Sean Christopherson
2019-01-22 18:40 ` Greg Kroah-Hartman
2019-01-22 20:39 ` Christian Borntraeger
2019-01-22 20:48 ` Greg Kroah-Hartman
2019-01-22 23:11 ` Paolo Bonzini
2019-01-23 8:28 ` Christian Borntraeger
-- strict thread matches above, loose matches on Subject: below --
2018-05-29 16:22 Greg Kroah-Hartman
2018-05-29 17:06 ` Paolo Bonzini
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