From: Paolo Bonzini <pbonzini@redhat.com>
To: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
Thomas Gleixner <tglx@linutronix.de>,
Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
x86@kernel.org
Cc: linux-kernel@vger.kernel.org, "Radim Krčmář" <rkrcmar@redhat.com>,
"H. Peter Anvin" <hpa@zytor.com>,
kvm@vger.kernel.org
Subject: Re: [PATCH 3/6] x86: kvm: no need to check return value of debugfs_create functions
Date: Fri, 25 Jan 2019 18:49:47 +0100 [thread overview]
Message-ID: <5495f33a-8d15-6f1a-36be-fa980831e830@redhat.com> (raw)
In-Reply-To: <20190122143542.8816-4-gregkh@linuxfoundation.org>
On 22/01/19 15:35, 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.
>
> Cc: Paolo Bonzini <pbonzini@redhat.com>
> Cc: "Radim Krčmář" <rkrcmar@redhat.com>
> Cc: Thomas Gleixner <tglx@linutronix.de>
> Cc: Ingo Molnar <mingo@redhat.com>
> Cc: Borislav Petkov <bp@alien8.de>
> Cc: "H. Peter Anvin" <hpa@zytor.com>
> Cc: <x86@kernel.org>
> Cc: <kvm@vger.kernel.org>
> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> ---
> arch/x86/kvm/debugfs.c | 26 ++++++++------------------
> 1 file changed, 8 insertions(+), 18 deletions(-)
>
> diff --git a/arch/x86/kvm/debugfs.c b/arch/x86/kvm/debugfs.c
> index c19c7ede9bd6..827cd58400d2 100644
> --- a/arch/x86/kvm/debugfs.c
> +++ b/arch/x86/kvm/debugfs.c
> @@ -43,26 +43,16 @@ DEFINE_SIMPLE_ATTRIBUTE(vcpu_tsc_scaling_frac_fops, vcpu_get_tsc_scaling_frac_bi
>
> int kvm_arch_create_vcpu_debugfs(struct kvm_vcpu *vcpu)
> {
> - struct dentry *ret;
> -
> - ret = debugfs_create_file("tsc-offset", 0444,
> - vcpu->debugfs_dentry,
> - vcpu, &vcpu_tsc_offset_fops);
> - if (!ret)
> - return -ENOMEM;
> + debugfs_create_file("tsc-offset", 0444, vcpu->debugfs_dentry, vcpu,
> + &vcpu_tsc_offset_fops);
>
> if (kvm_has_tsc_control) {
> - ret = debugfs_create_file("tsc-scaling-ratio", 0444,
> - vcpu->debugfs_dentry,
> - vcpu, &vcpu_tsc_scaling_fops);
> - if (!ret)
> - return -ENOMEM;
> - ret = debugfs_create_file("tsc-scaling-ratio-frac-bits", 0444,
> - vcpu->debugfs_dentry,
> - vcpu, &vcpu_tsc_scaling_frac_fops);
> - if (!ret)
> - return -ENOMEM;
> -
> + debugfs_create_file("tsc-scaling-ratio", 0444,
> + vcpu->debugfs_dentry, vcpu,
> + &vcpu_tsc_scaling_fops);
> + debugfs_create_file("tsc-scaling-ratio-frac-bits", 0444,
> + vcpu->debugfs_dentry, vcpu,
> + &vcpu_tsc_scaling_frac_fops);
> }
>
> return 0;
>
I'm still not sure about this. I think it's better if debugfs files are
created "all or none", i.e. something like
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 5ecea812cb6a..ce70c30b2861 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -2573,9 +2573,7 @@ static int kvm_vm_ioctl_create_vcpu(
if (r)
goto vcpu_destroy;
- r = kvm_create_vcpu_debugfs(vcpu);
- if (r)
- goto vcpu_destroy;
+ kvm_create_vcpu_debugfs(vcpu);
mutex_lock(&kvm->lock);
if (kvm_get_vcpu_by_id(kvm, id)) {
Paolo
next prev parent reply other threads:[~2019-01-25 17:50 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-01-22 14:35 [PATCH 0/6] x86: cleanup debugfs usage Greg Kroah-Hartman
2019-01-22 14:35 ` [PATCH 1/6] x86: mce: no need to check return value of debugfs_create functions Greg Kroah-Hartman
2019-01-22 21:53 ` Borislav Petkov
2019-01-22 14:35 ` [PATCH 2/6] x86: kdebugfs: " Greg Kroah-Hartman
2019-01-22 14:35 ` [PATCH 3/6] x86: kvm: " Greg Kroah-Hartman
2019-01-25 17:49 ` Paolo Bonzini [this message]
2019-01-26 13:53 ` Greg Kroah-Hartman
2019-01-28 9:19 ` Paolo Bonzini
2019-01-22 14:35 ` [PATCH 4/6] x86: mm: " Greg Kroah-Hartman
2019-01-22 14:35 ` [PATCH 5/6] x86: platform: " Greg Kroah-Hartman
2019-01-22 14:35 ` [PATCH 6/6] x86: xen: " Greg Kroah-Hartman
2019-01-23 8:53 ` Juergen Gross
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=5495f33a-8d15-6f1a-36be-fa980831e830@redhat.com \
--to=pbonzini@redhat.com \
--cc=bp@alien8.de \
--cc=gregkh@linuxfoundation.org \
--cc=hpa@zytor.com \
--cc=kvm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@redhat.com \
--cc=rkrcmar@redhat.com \
--cc=tglx@linutronix.de \
--cc=x86@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).