From: Sean Christopherson <sean.j.christopherson@intel.com>
To: Paolo Bonzini <pbonzini@redhat.com>
Cc: Randy Dunlap <rdunlap@infradead.org>,
Stephen Rothwell <sfr@canb.auug.org.au>,
Linux Next Mailing List <linux-next@vger.kernel.org>,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
KVM <kvm@vger.kernel.org>, Vitaly Kuznetsov <vkuznets@redhat.com>,
Wanpeng Li <wanpengli@tencent.com>,
Jim Mattson <jmattson@google.com>, Joerg Roedel <joro@8bytes.org>
Subject: Re: linux-next: Tree for Mar 25 (arch/x86/kvm/)
Date: Wed, 25 Mar 2020 09:46:06 -0700 [thread overview]
Message-ID: <20200325164606.GH14294@linux.intel.com> (raw)
In-Reply-To: <7b71119b-4594-2535-24ba-2c59430e4f30@redhat.com>
On Wed, Mar 25, 2020 at 05:26:20PM +0100, Paolo Bonzini wrote:
> On 25/03/20 17:14, Sean Christopherson wrote:
> >> Doh, right. I think the only solution for that one is to degrade it to
> >> WARN_ON(1).
> > I reproduced the error, give me a bit to play with the code to see if the
> > BUILD_BUG can be preserved. I'm curious as to why kvm_cpu_cap_mask() is
> > special, and why it only fails with this config.
> >
>
> I could not reproduce it, but I would not be surprised if there are
> other configurations where the compiler cannot constant-propagate from
> the reverse_cpuid struct into __cpuid_entry_get_reg.
The error is related to UBSAN. There is at least one legitimate (but benign)
underlying issue. I'm chasing down a second instance of the BUILD_BUG.
Assuming all issues can be fixed, I think it'd make sense to keep the
BUILD_BUG, especially if it's teasing out actual weirdness, even if the
weirdness is benign.
next prev parent reply other threads:[~2020-03-25 16:46 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-03-25 8:53 linux-next: Tree for Mar 25 Stephen Rothwell
2020-03-25 15:30 ` linux-next: Tree for Mar 25 (arch/x86/kvm/) Randy Dunlap
2020-03-25 15:32 ` Sean Christopherson
2020-03-25 15:46 ` Paolo Bonzini
2020-03-25 15:57 ` Randy Dunlap
2020-03-25 16:08 ` Paolo Bonzini
2020-03-25 16:14 ` Sean Christopherson
2020-03-25 16:26 ` Paolo Bonzini
2020-03-25 16:46 ` Sean Christopherson [this message]
2020-03-25 18:47 ` Sean Christopherson
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=20200325164606.GH14294@linux.intel.com \
--to=sean.j.christopherson@intel.com \
--cc=jmattson@google.com \
--cc=joro@8bytes.org \
--cc=kvm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-next@vger.kernel.org \
--cc=pbonzini@redhat.com \
--cc=rdunlap@infradead.org \
--cc=sfr@canb.auug.org.au \
--cc=vkuznets@redhat.com \
--cc=wanpengli@tencent.com \
/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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.