From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pf1-f202.google.com (mail-pf1-f202.google.com [209.85.210.202]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4785041A917 for ; Tue, 14 Jul 2026 18:43:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.202 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784054623; cv=none; b=dPhsICbGl140j4kBjzeb/YvTZ2yOcLqWxDELIkTj+sJX7Mz4c9Gets1rDqfuSVlBgiKYBF+2X2rdKD8iXfsOnMjAe1/mGLtLJK066WAF429GmIVZTMlspaUT8WNQeGrUfxCwE4kGDrmeC6EK8NB5LJRyiImaIpIAxgLbMNoTflY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784054623; c=relaxed/simple; bh=0Cxt8qE06Or/jQL8clXHIMUHQkQVbLUBxaPpYh+HO6w=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=cEr1CRqH66EBPZL0elYIp5g17mmIwV7N7PYK/0s5gcHsOYbbaz+hfQzb4kjtWfGDTk3kB03l0Xm6Gh8t3XJwX3ohwAqdJAdn/M14oARXL6j0DV2TwKINGTm1K5OYz/Ror6vFrakM4uj6m1R5ti7N/L87jcQG9tsvhPaPObSihHU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=DMUDT1ov; arc=none smtp.client-ip=209.85.210.202 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="DMUDT1ov" Received: by mail-pf1-f202.google.com with SMTP id d2e1a72fcca58-84859a64079so8332072b3a.3 for ; Tue, 14 Jul 2026 11:43:36 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1784054615; x=1784659415; darn=vger.kernel.org; h=content-type:cc:to:from:subject:message-id:references:mime-version :in-reply-to:date:from:to:cc:subject:date:message-id:reply-to :content-type; bh=rFM73Nl0bWyUMJUomM5RdFpNF5aybZxuz1pkz9xV3sw=; b=DMUDT1ovU2EeL+NddwKYGRCPCweeER39Iu9QEfk0M1UzJHwT85hdhiTSoOq5FV73de vUoHeld5mZZ/zhrWmk4e39o/JyVS6Zjs5wPFFnaU6NaIK7LurEwP6MJGR9b0IQ6qK/Q2 ErVkTTraghHEGl1qMbIyWv9gUtd6DfoGrTJjp0nwv8cSleIZSOVgHXyLYYGoh27viJpq ElWZNGoWaoRH9Q4f56gcNNRyXWvu8VQ+O+m1sXqZ8x9cq9WMMDG/r0XGPQScz1IBu9y8 vxQOae3pKbYGKt3ynLd/FxUcd6+Vu+sTq+FzWGKHPmNPGA7BXOiRZyF4GEq9UmX+he3E os6Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1784054615; x=1784659415; h=content-type:cc:to:from:subject:message-id:references:mime-version :in-reply-to:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to:content-type; bh=rFM73Nl0bWyUMJUomM5RdFpNF5aybZxuz1pkz9xV3sw=; b=Rdxwcw+6lQuNZf4TZGH+2g6zyIsOgPrY3xsS9Ebuv6YR0vx2lm5EujGHZP+WsOSBsV kmqQ7n0iZ8Co0RZ6tPZX2z/yCslNkEUFc18k1hObUF6Gi9L0DI+axtLV5qobpQoMEPj0 yFGUx7yUqpAiR0DPNfAl8+LysYsqYmc0poI+iRW7n5g9pvAoGBbiFJkTf5UXwyIaN/Ij 5h1+GQmpYIE+B0yvJte37PXXyUqY77f6OYMTx5qdhEzfL3lqs8KcwondqJCsxfIyjLXa Mp6gx1egoaAHzdckOh7ibLZbsQpgJNka6q7CkJkM5UbahMeWDmggrmgrkUWJHny2JvBP rRKA== X-Forwarded-Encrypted: i=1; AHgh+RrP37ecMlFoB8ptSn154Qkgm5jk38W3w3sKPSpY5KUT4t8RnYNe7louPvVZQ5zpRG3otuWJSP7S/sXRfO4=@vger.kernel.org X-Gm-Message-State: AOJu0YzdMdR63Ekj2IOMp52xAJfWMP+EJmuxBjQ+69N4PeSzS8YJUc3D uRh2TU2jWMT+w27r3sSscMKUISDng8t8WiIFUFd0c30eHDvWjzJZyEQWPNO0QcOcHuM++ihfVMw LiUXRwQ== X-Received: from pfnw16.prod.google.com ([2002:aa7:8590:0:b0:848:57f0:bf20]) (user=seanjc job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6a00:3d55:b0:845:4fec:3f8f with SMTP id d2e1a72fcca58-84a55894653mr3684533b3a.40.1784054614662; Tue, 14 Jul 2026 11:43:34 -0700 (PDT) Date: Tue, 14 Jul 2026 11:41:09 -0700 In-Reply-To: <1782119051448443.14545.seg@mailgw.kylinos.cn> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <1782119051448443.14545.seg@mailgw.kylinos.cn> X-Mailer: git-send-email 2.55.0.141.g00534a21ce-goog Message-ID: <178405354318.3120836.11122335012620649935.b4-ty@google.com> Subject: Re: [PATCH] KVM: Nullify irqfd->producer when add_producer() fails From: Sean Christopherson To: Sean Christopherson , leixiang Cc: stable@vger.kernel.org, Madhavan Srinivasan , Nicholas Piggin , Michael Ellerman , "Christophe Leroy (CS GROUP)" , Paolo Bonzini , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Paul Mackerras , Suresh Warrier , linuxppc-dev@lists.ozlabs.org, kvm@vger.kernel.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" On Mon, 22 Jun 2026 15:51:01 +0800, leixiang wrote: > The x86 and powerpc add_producer() callbacks set irqfd->producer before the > fallible setup and never clear it on error. The bypass manager doesn't > register a producer whose add_producer() failed -- producer->eventfd is > left NULL, so the later unregister early-returns and del_producer() is > never called -- so nothing ever drops the pointer. > > For VFIO PCI the producer is embedded in struct vfio_pci_irq_ctx and freed > when the vector is disabled, after which a routing update dereferences the > dangling pointer via kvm_arch_update_irqfd_routing(). > > [...] Applied to kvm-x86 fixes, thanks! [1/1] KVM: Nullify irqfd->producer when add_producer() fails https://github.com/kvm-x86/linux/commit/ed446e8aa894 -- https://github.com/kvm-x86/linux/tree/next