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=-17.3 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 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 34197C433DB for ; Sun, 14 Feb 2021 21:18:33 +0000 (UTC) Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id CDEF864DFF for ; Sun, 14 Feb 2021 21:18:32 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CDEF864DFF Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=xen.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=xen-devel-bounces@lists.xenproject.org Received: from list by lists.xenproject.org with outflank-mailman.85009.159310 (Exim 4.92) (envelope-from ) id 1lBOmJ-0001Os-TT; Sun, 14 Feb 2021 21:18:03 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 85009.159310; Sun, 14 Feb 2021 21:18:03 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1lBOmJ-0001Ol-Ol; Sun, 14 Feb 2021 21:18:03 +0000 Received: by outflank-mailman (input) for mailman id 85009; Sun, 14 Feb 2021 21:18:02 +0000 Received: from mail.xenproject.org ([104.130.215.37]) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1lBOmI-0001Og-3n for xen-devel@lists.xenproject.org; Sun, 14 Feb 2021 21:18:02 +0000 Received: from xenbits.xenproject.org ([104.239.192.120]) by mail.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1lBOmF-0002tO-Rd; Sun, 14 Feb 2021 21:17:59 +0000 Received: from [54.239.6.185] (helo=a483e7b01a66.ant.amazon.com) by xenbits.xenproject.org with esmtpsa (TLS1.3:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.92) (envelope-from ) id 1lBOmF-0006vA-Ir; Sun, 14 Feb 2021 21:17:59 +0000 X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=xen.org; s=20200302mail; h=Content-Transfer-Encoding:Content-Type:In-Reply-To: MIME-Version:Date:Message-ID:From:References:Cc:To:Subject; bh=/QYTDglDUzmSr9H0s41Nh/i0d4YrXWxPDKOebpqx8dE=; b=NcY8RSnZ3LKaGcib3T0HtChLhF M1sLaMxJGp/Kp2l4MeydJBd2feanETtRQcVu06AuiG4/2zW30vwcvB+BBKHyQJrkYanE817356IgL 8AoJUiKNh+Lp/4nQUrIV37x4O/nhjAkAEWpn2K/Ca8ELj/RVIL+ETmjzuONRlMF2jgK0=; Subject: Re: [PATCH v2 1/8] xen/events: reset affinity of 2-level event when tearing it down To: Juergen Gross , xen-devel@lists.xenproject.org, linux-kernel@vger.kernel.org Cc: Boris Ostrovsky , Stefano Stabellini , stable@vger.kernel.org References: <20210211101616.13788-1-jgross@suse.com> <20210211101616.13788-2-jgross@suse.com> From: Julien Grall Message-ID: <2abf73b0-ec8d-8e9a-665a-1adc47972fe7@xen.org> Date: Sun, 14 Feb 2021 21:17:57 +0000 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:78.0) Gecko/20100101 Thunderbird/78.7.1 MIME-Version: 1.0 In-Reply-To: <20210211101616.13788-2-jgross@suse.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-GB Content-Transfer-Encoding: 7bit Hi Juergen, On 11/02/2021 10:16, Juergen Gross wrote: > When creating a new event channel with 2-level events the affinity > needs to be reset initially in order to avoid using an old affinity > from earlier usage of the event channel port. So when tearing an event > channel down reset all affinity bits. > > The same applies to the affinity when onlining a vcpu: all old > affinity settings for this vcpu must be reset. As percpu events get > initialized before the percpu event channel hook is called, > resetting of the affinities happens after offlining a vcpu (this is > working, as initial percpu memory is zeroed out). > > Cc: stable@vger.kernel.org > Reported-by: Julien Grall > Signed-off-by: Juergen Gross Reviewed-by: Julien Grall Cheers, > --- > V2: > - reset affinity when tearing down the event (Julien Grall) > --- > drivers/xen/events/events_2l.c | 15 +++++++++++++++ > drivers/xen/events/events_base.c | 1 + > drivers/xen/events/events_internal.h | 8 ++++++++ > 3 files changed, 24 insertions(+) > > diff --git a/drivers/xen/events/events_2l.c b/drivers/xen/events/events_2l.c > index da87f3a1e351..a7f413c5c190 100644 > --- a/drivers/xen/events/events_2l.c > +++ b/drivers/xen/events/events_2l.c > @@ -47,6 +47,11 @@ static unsigned evtchn_2l_max_channels(void) > return EVTCHN_2L_NR_CHANNELS; > } > > +static void evtchn_2l_remove(evtchn_port_t evtchn, unsigned int cpu) > +{ > + clear_bit(evtchn, BM(per_cpu(cpu_evtchn_mask, cpu))); > +} > + > static void evtchn_2l_bind_to_cpu(evtchn_port_t evtchn, unsigned int cpu, > unsigned int old_cpu) > { > @@ -355,9 +360,18 @@ static void evtchn_2l_resume(void) > EVTCHN_2L_NR_CHANNELS/BITS_PER_EVTCHN_WORD); > } > > +static int evtchn_2l_percpu_deinit(unsigned int cpu) > +{ > + memset(per_cpu(cpu_evtchn_mask, cpu), 0, sizeof(xen_ulong_t) * > + EVTCHN_2L_NR_CHANNELS/BITS_PER_EVTCHN_WORD); > + > + return 0; > +} > + > static const struct evtchn_ops evtchn_ops_2l = { > .max_channels = evtchn_2l_max_channels, > .nr_channels = evtchn_2l_max_channels, > + .remove = evtchn_2l_remove, > .bind_to_cpu = evtchn_2l_bind_to_cpu, > .clear_pending = evtchn_2l_clear_pending, > .set_pending = evtchn_2l_set_pending, > @@ -367,6 +381,7 @@ static const struct evtchn_ops evtchn_ops_2l = { > .unmask = evtchn_2l_unmask, > .handle_events = evtchn_2l_handle_events, > .resume = evtchn_2l_resume, > + .percpu_deinit = evtchn_2l_percpu_deinit, > }; > > void __init xen_evtchn_2l_init(void) > diff --git a/drivers/xen/events/events_base.c b/drivers/xen/events/events_base.c > index e850f79351cb..6c539db81f8f 100644 > --- a/drivers/xen/events/events_base.c > +++ b/drivers/xen/events/events_base.c > @@ -368,6 +368,7 @@ static int xen_irq_info_pirq_setup(unsigned irq, > static void xen_irq_info_cleanup(struct irq_info *info) > { > set_evtchn_to_irq(info->evtchn, -1); > + xen_evtchn_port_remove(info->evtchn, info->cpu); > info->evtchn = 0; > channels_on_cpu_dec(info); > } > diff --git a/drivers/xen/events/events_internal.h b/drivers/xen/events/events_internal.h > index 0a97c0549db7..18a4090d0709 100644 > --- a/drivers/xen/events/events_internal.h > +++ b/drivers/xen/events/events_internal.h > @@ -14,6 +14,7 @@ struct evtchn_ops { > unsigned (*nr_channels)(void); > > int (*setup)(evtchn_port_t port); > + void (*remove)(evtchn_port_t port, unsigned int cpu); > void (*bind_to_cpu)(evtchn_port_t evtchn, unsigned int cpu, > unsigned int old_cpu); > > @@ -54,6 +55,13 @@ static inline int xen_evtchn_port_setup(evtchn_port_t evtchn) > return 0; > } > > +static inline void xen_evtchn_port_remove(evtchn_port_t evtchn, > + unsigned int cpu) > +{ > + if (evtchn_ops->remove) > + evtchn_ops->remove(evtchn, cpu); > +} > + > static inline void xen_evtchn_port_bind_to_cpu(evtchn_port_t evtchn, > unsigned int cpu, > unsigned int old_cpu) > -- Julien Grall