From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id BAD7F31159C for ; Thu, 16 Oct 2025 09:11:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760605882; cv=none; b=pitWfAkqMrujCFINt125f1jhy0R2SNQZ5I/xJ193e1GslZ1LfPr/eK4mZpdIWQZPHO/zKwHXYPhwumCNiItixavCdRFNYBYax9wx99Fd8UZyiOTPbeKQVzu5EejNWFf/9QM/byY92B/52It8DFNMfqkmcJilyEsJDsD5jksG0Pg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760605882; c=relaxed/simple; bh=1j35dzZsjccbWc/yB4/Ab3Ko3hCH5ysIKmWMDN3mbx4=; h=Subject:To:Cc:From:Date:Message-ID:MIME-Version:Content-Type; b=tnVpmxdCF9cIy46jT0tttPtCBICI4qQT1lUR7Bt0rxIrkyf5PzXuFriSRyb44nD4Xzt0mfvvWWt4RA6or2MSnW+dMJy/oW2ZZ5SnHgZxN/rviTS1thJ7ZmSWxBZRgHRRE6b7eRrg258do/fmezXvcmdbbpktnQ2LvKvKOwBUH3Q= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=ewDVMYGR; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="ewDVMYGR" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 46DC2C4CEF1; Thu, 16 Oct 2025 09:11:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1760605882; bh=1j35dzZsjccbWc/yB4/Ab3Ko3hCH5ysIKmWMDN3mbx4=; h=Subject:To:Cc:From:Date:From; b=ewDVMYGRU4509L/tDO8IYLoitT0dq5Pzbhz8EirBJHzYtAB8vpOpUkpXUThKnSKHM jdPZlf9U8g4c1dvlMr5nmZw6DlfGUcgkdfe3GN3wP0wH7Fkg73Xp5899ftHkVcJu6p kt3VuTa4VBgcklCsABFEqhC2jjYaTiXEkoxJ7S70= Subject: FAILED: patch "[PATCH] xen/events: Return -EEXIST for bound VIRQs" failed to apply to 6.1-stable tree To: jason.andryuk@amd.com,jgross@suse.com Cc: From: Date: Thu, 16 Oct 2025 11:10:25 +0200 Message-ID: <2025101625-gully-disaster-8717@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit The patch below does not apply to the 6.1-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.1.y git checkout FETCH_HEAD git cherry-pick -x 07ce121d93a5e5fb2440a24da3dbf408fcee978e # git commit -s git send-email --to '' --in-reply-to '2025101625-gully-disaster-8717@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 07ce121d93a5e5fb2440a24da3dbf408fcee978e Mon Sep 17 00:00:00 2001 From: Jason Andryuk Date: Wed, 27 Aug 2025 20:36:02 -0400 Subject: [PATCH] xen/events: Return -EEXIST for bound VIRQs Change find_virq() to return -EEXIST when a VIRQ is bound to a different CPU than the one passed in. With that, remove the BUG_ON() from bind_virq_to_irq() to propogate the error upwards. Some VIRQs are per-cpu, but others are per-domain or global. Those must be bound to CPU0 and can then migrate elsewhere. The lookup for per-domain and global will probably fail when migrated off CPU 0, especially when the current CPU is tracked. This now returns -EEXIST instead of BUG_ON(). A second call to bind a per-domain or global VIRQ is not expected, but make it non-fatal to avoid trying to look up the irq, since we don't know which per_cpu(virq_to_irq) it will be in. Cc: stable@vger.kernel.org Signed-off-by: Jason Andryuk Reviewed-by: Juergen Gross Signed-off-by: Juergen Gross Message-ID: <20250828003604.8949-3-jason.andryuk@amd.com> diff --git a/drivers/xen/events/events_base.c b/drivers/xen/events/events_base.c index 374231d84e4f..b060b5a95f45 100644 --- a/drivers/xen/events/events_base.c +++ b/drivers/xen/events/events_base.c @@ -1314,10 +1314,12 @@ int bind_interdomain_evtchn_to_irq_lateeoi(struct xenbus_device *dev, } EXPORT_SYMBOL_GPL(bind_interdomain_evtchn_to_irq_lateeoi); -static int find_virq(unsigned int virq, unsigned int cpu, evtchn_port_t *evtchn) +static int find_virq(unsigned int virq, unsigned int cpu, evtchn_port_t *evtchn, + bool percpu) { struct evtchn_status status; evtchn_port_t port; + bool exists = false; memset(&status, 0, sizeof(status)); for (port = 0; port < xen_evtchn_max_channels(); port++) { @@ -1330,12 +1332,16 @@ static int find_virq(unsigned int virq, unsigned int cpu, evtchn_port_t *evtchn) continue; if (status.status != EVTCHNSTAT_virq) continue; - if (status.u.virq == virq && status.vcpu == xen_vcpu_nr(cpu)) { + if (status.u.virq != virq) + continue; + if (status.vcpu == xen_vcpu_nr(cpu)) { *evtchn = port; return 0; + } else if (!percpu) { + exists = true; } } - return -ENOENT; + return exists ? -EEXIST : -ENOENT; } /** @@ -1382,8 +1388,11 @@ int bind_virq_to_irq(unsigned int virq, unsigned int cpu, bool percpu) evtchn = bind_virq.port; else { if (ret == -EEXIST) - ret = find_virq(virq, cpu, &evtchn); - BUG_ON(ret < 0); + ret = find_virq(virq, cpu, &evtchn, percpu); + if (ret) { + __unbind_from_irq(info, info->irq); + goto out; + } } ret = xen_irq_info_virq_setup(info, cpu, evtchn, virq);