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=-13.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham 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 32493C433E6 for ; Sat, 13 Mar 2021 13:30:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 081ED64F2B for ; Sat, 13 Mar 2021 13:30:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233671AbhCMN3r (ORCPT ); Sat, 13 Mar 2021 08:29:47 -0500 Received: from forward2-smtp.messagingengine.com ([66.111.4.226]:34061 "EHLO forward2-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233509AbhCMN3P (ORCPT ); Sat, 13 Mar 2021 08:29:15 -0500 Received: from compute4.internal (compute4.nyi.internal [10.202.2.44]) by mailforward.nyi.internal (Postfix) with ESMTP id 56C191941E07; Sat, 13 Mar 2021 08:29:15 -0500 (EST) Received: from mailfrontend2 ([10.202.2.163]) by compute4.internal (MEProxy); Sat, 13 Mar 2021 08:29:15 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:content-transfer-encoding:content-type :date:from:message-id:mime-version:subject:to:x-me-proxy :x-me-proxy:x-me-sender:x-me-sender:x-sasl-enc; s=fm2; bh=JUXhCa OEe68c/AjioIPr5syfBk6wpLXdhVpYYXWoIxs=; b=uxjFkAFMU4x5Ec8IUY23L0 wTZbqDdrC9yc3/M4avIHCRf+DLVSpoRxVM0tiN5j5tn2VpfCOO+r0fKEtFg1fz0C tikvRWHABQ9xRLn5jGYyzSD5aRFbINre5v3CE0wFVKisbjFz16Ee/5UrdU9SnK2C zJCnDupn2sxUtVugIIdEu7YqlhOm9FA2l4Xi63+nB5s6ONdE1mkOVm2rQAxmVFod fSzxLC5LphwMfZN39NMRcw+tw3n7aG9lTNWEksm7umJj+BVpM+G+iYWz6Nw3Apaj DwFI8wcCGbZSBsc/9Wq+SuFpdqmep5kQEmVYkwWr0zgCWV+pZNNHo4Y40fsan5WA == X-ME-Sender: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgeduledruddvgedgheduucetufdoteggodetrfdotf fvucfrrhhofhhilhgvmecuhfgrshhtofgrihhlpdfqfgfvpdfurfetoffkrfgpnffqhgen uceurghilhhouhhtmecufedttdenucenucfjughrpefuvffhfffkgggtgfesthekredttd dtlfenucfhrhhomhepoehgrhgvghhkhheslhhinhhugihfohhunhgurghtihhonhdrohhr gheqnecuggftrfgrthhtvghrnhepleelledvgeefleeltdetgedugeffgffhudffudduke egfeelgeeigeekjefhleevnecuffhomhgrihhnpehkvghrnhgvlhdrohhrghenucfkphep keefrdekiedrjeegrdeigeenucevlhhushhtvghrufhiiigvpeejnecurfgrrhgrmhepmh grihhlfhhrohhmpehgrhgvgheskhhrohgrhhdrtghomh X-ME-Proxy: Received: from localhost (83-86-74-64.cable.dynamic.v4.ziggo.nl [83.86.74.64]) by mail.messagingengine.com (Postfix) with ESMTPA id D5C411080057; Sat, 13 Mar 2021 08:29:14 -0500 (EST) Subject: FAILED: patch "[PATCH] xen/events: avoid handling the same event on two cpus at the" failed to apply to 4.14-stable tree To: jgross@suse.com, boris.ostrovsky@oracle.com, jgrall@amazon.com, julien@xen.org Cc: From: Date: Sat, 13 Mar 2021 14:29:09 +0100 Message-ID: <16156421491992@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org The patch below does not apply to the 4.14-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 . thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From b6622798bc50b625a1e62f82c7190df40c1f5b21 Mon Sep 17 00:00:00 2001 From: Juergen Gross Date: Sat, 6 Mar 2021 17:18:33 +0100 Subject: [PATCH] xen/events: avoid handling the same event on two cpus at the same time When changing the cpu affinity of an event it can happen today that (with some unlucky timing) the same event will be handled on the old and the new cpu at the same time. Avoid that by adding an "event active" flag to the per-event data and call the handler only if this flag isn't set. Cc: stable@vger.kernel.org Reported-by: Julien Grall Signed-off-by: Juergen Gross Reviewed-by: Julien Grall Link: https://lore.kernel.org/r/20210306161833.4552-4-jgross@suse.com Signed-off-by: Boris Ostrovsky diff --git a/drivers/xen/events/events_base.c b/drivers/xen/events/events_base.c index b27c012c86b5..8236e2364eeb 100644 --- a/drivers/xen/events/events_base.c +++ b/drivers/xen/events/events_base.c @@ -103,6 +103,7 @@ struct irq_info { #define EVT_MASK_REASON_EXPLICIT 0x01 #define EVT_MASK_REASON_TEMPORARY 0x02 #define EVT_MASK_REASON_EOI_PENDING 0x04 + u8 is_active; /* Is event just being handled? */ unsigned irq; evtchn_port_t evtchn; /* event channel */ unsigned short cpu; /* cpu bound */ @@ -810,6 +811,12 @@ static void xen_evtchn_close(evtchn_port_t port) BUG(); } +static void event_handler_exit(struct irq_info *info) +{ + smp_store_release(&info->is_active, 0); + clear_evtchn(info->evtchn); +} + static void pirq_query_unmask(int irq) { struct physdev_irq_status_query irq_status; @@ -828,14 +835,15 @@ static void pirq_query_unmask(int irq) static void eoi_pirq(struct irq_data *data) { - evtchn_port_t evtchn = evtchn_from_irq(data->irq); + struct irq_info *info = info_for_irq(data->irq); + evtchn_port_t evtchn = info ? info->evtchn : 0; struct physdev_eoi eoi = { .irq = pirq_from_irq(data->irq) }; int rc = 0; if (!VALID_EVTCHN(evtchn)) return; - clear_evtchn(evtchn); + event_handler_exit(info); if (pirq_needs_eoi(data->irq)) { rc = HYPERVISOR_physdev_op(PHYSDEVOP_eoi, &eoi); @@ -1666,6 +1674,8 @@ void handle_irq_for_port(evtchn_port_t port, struct evtchn_loop_ctrl *ctrl) } info = info_for_irq(irq); + if (xchg_acquire(&info->is_active, 1)) + return; dev = (info->type == IRQT_EVTCHN) ? info->u.interdomain : NULL; if (dev) @@ -1853,12 +1863,11 @@ static void disable_dynirq(struct irq_data *data) static void ack_dynirq(struct irq_data *data) { - evtchn_port_t evtchn = evtchn_from_irq(data->irq); - - if (!VALID_EVTCHN(evtchn)) - return; + struct irq_info *info = info_for_irq(data->irq); + evtchn_port_t evtchn = info ? info->evtchn : 0; - clear_evtchn(evtchn); + if (VALID_EVTCHN(evtchn)) + event_handler_exit(info); } static void mask_ack_dynirq(struct irq_data *data) @@ -1874,7 +1883,7 @@ static void lateeoi_ack_dynirq(struct irq_data *data) if (VALID_EVTCHN(evtchn)) { do_mask(info, EVT_MASK_REASON_EOI_PENDING); - clear_evtchn(evtchn); + event_handler_exit(info); } } @@ -1885,7 +1894,7 @@ static void lateeoi_mask_ack_dynirq(struct irq_data *data) if (VALID_EVTCHN(evtchn)) { do_mask(info, EVT_MASK_REASON_EXPLICIT); - clear_evtchn(evtchn); + event_handler_exit(info); } } @@ -1998,10 +2007,11 @@ static void restore_cpu_ipis(unsigned int cpu) /* Clear an irq's pending state, in preparation for polling on it */ void xen_clear_irq_pending(int irq) { - evtchn_port_t evtchn = evtchn_from_irq(irq); + struct irq_info *info = info_for_irq(irq); + evtchn_port_t evtchn = info ? info->evtchn : 0; if (VALID_EVTCHN(evtchn)) - clear_evtchn(evtchn); + event_handler_exit(info); } EXPORT_SYMBOL(xen_clear_irq_pending); void xen_set_irq_pending(int irq)