linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Nitesh Narayan Lal <nitesh@redhat.com>
To: kvm@vger.kernel.org, linux-kernel@vger.kernel.org,
	pbonzini@redhat.com, mtosatti@redhat.com, rkrcmar@redhat.com,
	vkuznets@redhat.com, sean.j.christopherson@intel.com,
	wanpengli@tencent.com, jmattson@google.com, joro@8bytes.org
Subject: [PATCH] KVM: x86: Zero the IOAPIC scan request dest vCPUs bitmap
Date: Wed, 20 Nov 2019 07:12:24 -0500	[thread overview]
Message-ID: <20191120121224.9850-1-nitesh@redhat.com> (raw)

Not zeroing the bitmap used for identifying the destination vCPUs for an
IOAPIC scan request in fixed delivery mode could lead to waking up unwanted
vCPUs. This patch zeroes the vCPU bitmap before passing it to
kvm_bitmap_or_dest_vcpus(), which is responsible for setting the bitmap
with the bits corresponding to the destination vCPUs.

Fixes: 7ee30bc132c6("KVM: x86: deliver KVM IOAPIC scan request to target vCPUs")
Signed-off-by: Nitesh Narayan Lal <nitesh@redhat.com>
---
 arch/x86/kvm/ioapic.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/x86/kvm/ioapic.c b/arch/x86/kvm/ioapic.c
index ce30ef23c86b..9fd2dd89a1c5 100644
--- a/arch/x86/kvm/ioapic.c
+++ b/arch/x86/kvm/ioapic.c
@@ -332,6 +332,7 @@ static void ioapic_write_indirect(struct kvm_ioapic *ioapic, u32 val)
 			irq.delivery_mode = e->fields.delivery_mode << 8;
 			irq.dest_id = e->fields.dest_id;
 			irq.dest_mode = e->fields.dest_mode;
+			bitmap_zero(&vcpu_bitmap, 16);
 			kvm_bitmap_or_dest_vcpus(ioapic->kvm, &irq,
 						 &vcpu_bitmap);
 			if (old_dest_mode != e->fields.dest_mode ||
-- 
2.18.1


             reply	other threads:[~2019-11-20 12:12 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-11-20 12:12 Nitesh Narayan Lal [this message]
2019-11-20 12:33 ` Paolo Bonzini

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=20191120121224.9850-1-nitesh@redhat.com \
    --to=nitesh@redhat.com \
    --cc=jmattson@google.com \
    --cc=joro@8bytes.org \
    --cc=kvm@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mtosatti@redhat.com \
    --cc=pbonzini@redhat.com \
    --cc=rkrcmar@redhat.com \
    --cc=sean.j.christopherson@intel.com \
    --cc=vkuznets@redhat.com \
    --cc=wanpengli@tencent.com \
    --subject='Re: [PATCH] KVM: x86: Zero the IOAPIC scan request dest vCPUs bitmap' \
    /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

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).