From: Jim Mattson <jmattson@google.com>
To: Sean Christopherson <seanjc@google.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>,
kvm list <kvm@vger.kernel.org>,
LKML <linux-kernel@vger.kernel.org>,
Hao Sun <sunhao.th@gmail.com>
Subject: Re: [PATCH 2/3] KVM: Stop looking for coalesced MMIO zones if the bus is destroyed
Date: Thu, 15 Apr 2021 15:22:19 -0700 [thread overview]
Message-ID: <CALMp9eSQuDXg4nU0xmD7VHFnWpvsqGJ1SLudTf0nzx+nggk7DA@mail.gmail.com> (raw)
In-Reply-To: <20210412222050.876100-3-seanjc@google.com>
On Mon, Apr 12, 2021 at 3:21 PM Sean Christopherson <seanjc@google.com> wrote:
>
> Abort the walk of coalesced MMIO zones if kvm_io_bus_unregister_dev()
> fails to allocate memory for the new instance of the bus. If it can't
> instantiate a new bus, unregister_dev() destroys all devices _except_ the
> target device. But, it doesn't tell the caller that it obliterated the
> bus and invoked the destructor for all devices that were on the bus. In
> the coalesced MMIO case, this can result in a deleted list entry
> dereference due to attempting to continue iterating on coalesced_zones
> after future entries (in the walk) have been deleted.
>
> Opportunistically add curly braces to the for-loop, which encompasses
> many lines but sneaks by without braces due to the guts being a single
> if statement.
>
> Fixes: f65886606c2d ("KVM: fix memory leak in kvm_io_bus_unregister_dev()")
> Cc: stable@vger.kernel.org
> Reported-by: Hao Sun <sunhao.th@gmail.com>
> Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Jim Mattson <jmattson@google.com>
next prev parent reply other threads:[~2021-04-15 22:22 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-04-12 22:20 [PATCH 0/3] KVM: Fixes and a cleanup for coalesced MMIO Sean Christopherson
2021-04-12 22:20 ` [PATCH 1/3] KVM: Destroy I/O bus devices on unregister failure _after_ sync'ing SRCU Sean Christopherson
2021-04-15 21:50 ` Jim Mattson
2021-04-12 22:20 ` [PATCH 2/3] KVM: Stop looking for coalesced MMIO zones if the bus is destroyed Sean Christopherson
2021-04-15 22:22 ` Jim Mattson [this message]
2021-04-12 22:20 ` [PATCH 3/3] KVM: Add proper lockdep assertion in I/O bus unregister Sean Christopherson
2021-04-15 21:58 ` Jim Mattson
2021-04-15 22:15 ` Sean Christopherson
2021-04-17 13:11 ` [PATCH 0/3] KVM: Fixes and a cleanup for coalesced MMIO 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=CALMp9eSQuDXg4nU0xmD7VHFnWpvsqGJ1SLudTf0nzx+nggk7DA@mail.gmail.com \
--to=jmattson@google.com \
--cc=kvm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=pbonzini@redhat.com \
--cc=seanjc@google.com \
--cc=sunhao.th@gmail.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 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).