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 Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id AC86EEA8550 for ; Tue, 10 Mar 2026 10:04:09 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1vztwK-0006yB-QA; Tue, 10 Mar 2026 06:03:48 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1vztwH-0006xx-5d for qemu-devel@nongnu.org; Tue, 10 Mar 2026 06:03:45 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1vztwE-0005G4-Mm for qemu-devel@nongnu.org; Tue, 10 Mar 2026 06:03:44 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1773137021; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=F3Q3Fyd5WdTVLZJblLRKe/QRbH8clVosOiSNvQWDP7U=; b=Y2fJPKalK9qxZeEqCR5yAgfl+jMSc0jsMV7OI+0xsYcwoG/TM652o+u5hiRnem1M6hQBWe WaQu502eph5S0w3injErv5X4vyBVCOBcLBARJY/KgXlz/AsRHfsGNfAyDULeHBXASKd+xc 3Z9QhDUmeI8diHHbFO+/3+VFcX9wmXY= Received: from mx-prod-mc-03.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-570-2YAEAlYrM_milfcLqnv0xw-1; Tue, 10 Mar 2026 06:03:38 -0400 X-MC-Unique: 2YAEAlYrM_milfcLqnv0xw-1 X-Mimecast-MFC-AGG-ID: 2YAEAlYrM_milfcLqnv0xw_1773137017 Received: from mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.12]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id F14871956060; Tue, 10 Mar 2026 10:03:36 +0000 (UTC) Received: from blackfin.pond.sub.org (unknown [10.45.242.12]) by mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 8535619560A6; Tue, 10 Mar 2026 10:03:36 +0000 (UTC) Received: by blackfin.pond.sub.org (Postfix, from userid 1000) id 1CDCF21E675A; Tue, 10 Mar 2026 11:03:34 +0100 (CET) From: Markus Armbruster To: Ani Sinha Cc: Peter Xu , Fabiano Rosas , Prasad Pandit , qemu-devel@nongnu.org Subject: Re: [PATCH] migration: assert that the same migration handler is not being added twice In-Reply-To: <20260308100148.162503-1-anisinha@redhat.com> (Ani Sinha's message of "Sun, 8 Mar 2026 15:31:48 +0530") References: <20260308100148.162503-1-anisinha@redhat.com> Date: Tue, 10 Mar 2026 11:03:34 +0100 Message-ID: <87wlzkknm1.fsf@pond.sub.org> User-Agent: Gnus/5.13 (Gnus v5.13) MIME-Version: 1.0 Content-Type: text/plain X-Scanned-By: MIMEDefang 3.0 on 10.30.177.12 Received-SPF: pass client-ip=170.10.133.124; envelope-from=armbru@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -3 X-Spam_score: -0.4 X-Spam_bar: / X-Spam_report: (-0.4 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H5=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.819, RCVD_IN_VALIDITY_SAFE_BLOCKED=0.903, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=no autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: qemu development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Ani Sinha writes: > Currently the code that adds a migration blocker does not check if the same > blocker already exists. Assert that the migration handler being added has > not been added already. > > CC: Markus Armbruster > CC: Peter Xu > CC: Prasad Pandit > Signed-off-by: Ani Sinha > --- > migration/migration.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/migration/migration.c b/migration/migration.c > index a5b0465ed3..840cf0dfe2 100644 > --- a/migration/migration.c > +++ b/migration/migration.c > @@ -1702,6 +1702,8 @@ static int add_blockers(Error **reasonp, unsigned modes, Error **errp) > { > for (MigMode mode = 0; mode < MIG_MODE__MAX; mode++) { > if (modes & BIT(mode)) { > + assert(g_slist_index(migration_blockers[mode], > + *reasonp) == -1); Indentation is off. Have we run into such extra additions, or is this just out of caution? What would happen if such an extra addition went uncaught? > migration_blockers[mode] = g_slist_prepend(migration_blockers[mode], > *reasonp); > }