mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: Gal Pressman <gal@nvidia.com>
To: Sean Christopherson <seanjc@google.com>,
	Paolo Bonzini <pbonzini@redhat.com>,
	Thomas Gleixner <tglx@kernel.org>, Ingo Molnar <mingo@redhat.com>,
	Borislav Petkov <bp@alien8.de>,
	Dave Hansen <dave.hansen@linux.intel.com>, <x86@kernel.org>,
	"H. Peter Anvin" <hpa@zytor.com>,
	Naveen N Rao <naveen@kernel.org>, <kvm@vger.kernel.org>,
	<linux-kernel@vger.kernel.org>
Cc: Gal Pressman <gal@nvidia.com>
Subject: [PATCH v2 0/2] KVM: x86: Fix UBSAN bool warnings in module parameters
Date: Wed, 25 Feb 2026 16:50:48 +0200	[thread overview]
Message-ID: <20260225145050.2350278-1-gal@nvidia.com> (raw)

Several KVM module parameters use int to support a special -1 (auto)
value, but rely on param_get_bool() for the sysfs getter.
When userspace reads these parameters before the auto value is resolved,
param_get_bool() interprets the int as a bool, triggering UBSAN "load of
value 255 is not a valid value for type '_Bool'" warnings.

Fix both instances by implementing getter functions that handle the -1
case before falling through to param_get_bool().

Changelog -
v1->v2: https://lore.kernel.org/all/20260210064621.1902269-1-gal@nvidia.com/
* Show auto avic as 'N' (Naveen)

Gal Pressman (2):
  KVM: SVM: Fix UBSAN warning when reading avic parameter
  KVM: x86/mmu: Fix UBSAN warning when reading nx_huge_pages parameter

 arch/x86/kvm/mmu/mmu.c  |  5 +++++
 arch/x86/kvm/svm/avic.c | 13 ++++++++++++-
 2 files changed, 17 insertions(+), 1 deletion(-)

-- 
2.52.0


             reply	other threads:[~2026-02-25 14:51 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-02-25 14:50 Gal Pressman [this message]
2026-02-25 14:50 ` [PATCH v2 1/2] KVM: SVM: Fix UBSAN warning when reading avic parameter Gal Pressman
2026-02-26  5:35   ` Naveen N Rao
2026-02-25 14:50 ` [PATCH v2 2/2] KVM: x86/mmu: Fix UBSAN warning when reading nx_huge_pages parameter Gal Pressman
2026-03-05 17:08 ` [PATCH v2 0/2] KVM: x86: Fix UBSAN bool warnings in module parameters 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=20260225145050.2350278-1-gal@nvidia.com \
    --to=gal@nvidia.com \
    --cc=bp@alien8.de \
    --cc=dave.hansen@linux.intel.com \
    --cc=hpa@zytor.com \
    --cc=kvm@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@redhat.com \
    --cc=naveen@kernel.org \
    --cc=pbonzini@redhat.com \
    --cc=seanjc@google.com \
    --cc=tglx@kernel.org \
    --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

all inboxes | Powered by JetHome®