From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-18.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_IN_DEF_DKIM_WL autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2EE45C433B4 for ; Thu, 15 Apr 2021 21:50:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1048A610F7 for ; Thu, 15 Apr 2021 21:50:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236273AbhDOVup (ORCPT ); Thu, 15 Apr 2021 17:50:45 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50370 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236247AbhDOVuo (ORCPT ); Thu, 15 Apr 2021 17:50:44 -0400 Received: from mail-ot1-x329.google.com (mail-ot1-x329.google.com [IPv6:2607:f8b0:4864:20::329]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 55C23C061756 for ; Thu, 15 Apr 2021 14:50:19 -0700 (PDT) Received: by mail-ot1-x329.google.com with SMTP id i16-20020a9d68d00000b0290286edfdfe9eso13351873oto.3 for ; Thu, 15 Apr 2021 14:50:19 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=a4DOTBbYEKnT3EnjXiuFlp4qBusHe05Bi/ZftDfP8iI=; b=TMs3OTkoZpQrTMVqb9siJB81H/SU2Cyvmxywxt+jCDPZDntfBjWKju8NkqmM8LRauy 7mq11Y1DF+8t6GO9EJC+OGSDXGMUeqskaGEMsoKZ0I5NalIf7Qsy/iv+gnuqcmMky26s NTye3gCqGBfPMNKocHfwkpOjNG89fZAqmgetBwfa7qQl6fSG4GdjcxE88FBVK1/Km184 V2sZDVXWA5Dee3wZCXJhrJ0ZlqT5QMojlOGgcw2doeM2TazMY8pATAAPACTotEnQ9YIR m7O7rRVYVg6Y+hoytZiy9Ziuy003oMK+rxUyvxR5aIdn1xBrr4KXXmsfEmR128k6Vw8T 3yXw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=a4DOTBbYEKnT3EnjXiuFlp4qBusHe05Bi/ZftDfP8iI=; b=uiuzd1bsTKnb0uc602gWaakqwwESK4EHwPNx55mBGKA6902s9rInnokExzqMn5jNdG m4ot7dAgQY1u9Ma0kQoqYF5o2kyql9UuWi6m+PuPD7hMT7SdXDihuvQ9L8iXQ3Vn/2Ya Q/Hp/257bB6rzFFxFOihIiU3puC2fbLVXcD5DUPuYiDGhO3oYoAHtkel0rwLcdQTQfxB w8GhvvdNqfvRXOeyX5D+/zFuxt5p+i8gqqN9FC1GcE0pugIAsScPmcrtKI9+GuSumNRq 1DweG8HQIxKupVpo2zLUsZpluupsmSPLNcTAN2gqXtG6cMdYb3X+sfHo3QODTHBtisNO UJxA== X-Gm-Message-State: AOAM531GgzkIXcZ6GZNLYyolgG1lEhr1nYQ8sPYXP0Awl7Hbptgp34sQ kt95610LrcGQz32CybGWbu1j5HS83XqsoqDLeZkkmA== X-Google-Smtp-Source: ABdhPJwArKObs6KeZLmWKpYAJZakPx4EL1VEG6f5D8lDks543GYniDSSnRM6fFDXWgTL3A8vp0CsV2Ay1/oPYxpMers= X-Received: by 2002:a9d:2f29:: with SMTP id h38mr1039188otb.241.1618523418458; Thu, 15 Apr 2021 14:50:18 -0700 (PDT) MIME-Version: 1.0 References: <20210412222050.876100-1-seanjc@google.com> <20210412222050.876100-2-seanjc@google.com> In-Reply-To: <20210412222050.876100-2-seanjc@google.com> From: Jim Mattson Date: Thu, 15 Apr 2021 14:50:07 -0700 Message-ID: Subject: Re: [PATCH 1/3] KVM: Destroy I/O bus devices on unregister failure _after_ sync'ing SRCU To: Sean Christopherson Cc: Paolo Bonzini , kvm list , LKML , Hao Sun Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Mon, Apr 12, 2021 at 3:21 PM Sean Christopherson wrote: > > If allocating a new instance of an I/O bus fails when unregistering a > device, wait to destroy the device until after all readers are guaranteed > to see the new null bus. Destroying devices before the bus is nullified > could lead to use-after-free since readers expect the devices on their > reference of the bus to remain valid. > > Fixes: f65886606c2d ("KVM: fix memory leak in kvm_io_bus_unregister_dev()") > Cc: stable@vger.kernel.org > Signed-off-by: Sean Christopherson Reviewed-by: Jim Mattson