From patchwork Tue Nov 3 14:35:19 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: =?utf-8?b?SsO8cmdlbiBHcm/Dnw==?= X-Patchwork-Id: 317260 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=-12.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT 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 12667C5DF9D for ; Tue, 3 Nov 2020 14:35:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A6E322244C for ; Tue, 3 Nov 2020 14:35:55 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=suse.com header.i=@suse.com header.b="PZ1b+stH" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728107AbgKCOfy (ORCPT ); Tue, 3 Nov 2020 09:35:54 -0500 Received: from mx2.suse.de ([195.135.220.15]:47218 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728174AbgKCOfa (ORCPT ); Tue, 3 Nov 2020 09:35:30 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1604414129; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=9P/69LoF58OC45HuKlquzX19e/MHgDNFa/QJp/YzxiI=; b=PZ1b+stHCFP8qXTvzVsO96xoAxCMIOSEx0QHZXEzWI5DSAZVq1kL/cxhwv+uW410kSUbRO k25hLdfJtGJteVGEW46VgXFaBMLOJSv+cdo/6QodhFkEgw26X10QyKi7p3fTYZDimUVzaH qD5P/FY8zOcajiViRXHMarev/M3dijI= Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 2F481B2A5 for ; Tue, 3 Nov 2020 14:35:29 +0000 (UTC) From: Juergen Gross To: stable@vger.kernel.org Subject: [PATCH v2 04/13] xen/events: fix race in evtchn_fifo_unmask() Date: Tue, 3 Nov 2020 15:35:19 +0100 Message-Id: <20201103143528.22780-5-jgross@suse.com> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20201103143528.22780-1-jgross@suse.com> References: <20201103143528.22780-1-jgross@suse.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org Unmasking a fifo event channel can result in unmasking it twice, once directly in the kernel and once via a hypercall in case the event was pending. Fix that by doing the local unmask only if the event is not pending. This is part of XSA-332. This is upstream commit f01337197419b7e8a492e83089552b77d3b5fb90 Cc: stable@vger.kernel.org Signed-off-by: Juergen Gross Reviewed-by: Jan Beulich --- drivers/xen/events/events_fifo.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/drivers/xen/events/events_fifo.c b/drivers/xen/events/events_fifo.c index 7ef27c6ed72f..970a5eb6dca4 100644 --- a/drivers/xen/events/events_fifo.c +++ b/drivers/xen/events/events_fifo.c @@ -227,19 +227,25 @@ static bool evtchn_fifo_is_masked(unsigned port) return sync_test_bit(EVTCHN_FIFO_BIT(MASKED, word), BM(word)); } /* - * Clear MASKED, spinning if BUSY is set. + * Clear MASKED if not PENDING, spinning if BUSY is set. + * Return true if mask was cleared. */ -static void clear_masked(volatile event_word_t *word) +static bool clear_masked_cond(volatile event_word_t *word) { event_word_t new, old, w; w = *word; do { + if (w & (1 << EVTCHN_FIFO_PENDING)) + return false; + old = w & ~(1 << EVTCHN_FIFO_BUSY); new = old & ~(1 << EVTCHN_FIFO_MASKED); w = sync_cmpxchg(word, old, new); } while (w != old); + + return true; } static void evtchn_fifo_unmask(unsigned port) @@ -248,8 +254,7 @@ static void evtchn_fifo_unmask(unsigned port) BUG_ON(!irqs_disabled()); - clear_masked(word); - if (evtchn_fifo_is_pending(port)) { + if (!clear_masked_cond(word)) { struct evtchn_unmask unmask = { .port = port }; (void)HYPERVISOR_event_channel_op(EVTCHNOP_unmask, &unmask); } From patchwork Tue Nov 3 14:35:20 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: =?utf-8?b?SsO8cmdlbiBHcm/Dnw==?= X-Patchwork-Id: 317258 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=-12.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT 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 32FFDC56201 for ; Tue, 3 Nov 2020 14:35:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E9F9022450 for ; Tue, 3 Nov 2020 14:35:55 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=suse.com header.i=@suse.com header.b="HK3vNedI" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727988AbgKCOfx (ORCPT ); Tue, 3 Nov 2020 09:35:53 -0500 Received: from mx2.suse.de ([195.135.220.15]:47282 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728226AbgKCOfd (ORCPT ); Tue, 3 Nov 2020 09:35:33 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1604414129; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=lEs59R9DARVPC6XXl0ekdAY1h8qfIusTOl5aSiOcMR8=; b=HK3vNedIBeUOYCDXfQtxsAjLsFyJn8wOSl8OGnt23nTHd6dzWg7OB3ODodh4jvy4JDUK5i BHsmdHNIUeknn2ozyRzB7PzmJZNjE3+h2PDaQjhHBX1pKOC89vZ76Mq7mW3EfrGOLqf7vL piSBG4i6I4OQtlSV+yGZejSUor0XTKQ= Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 472C8B2A6 for ; Tue, 3 Nov 2020 14:35:29 +0000 (UTC) From: Juergen Gross To: stable@vger.kernel.org Subject: [PATCH v2 05/13] xen/events: add a new "late EOI" evtchn framework Date: Tue, 3 Nov 2020 15:35:20 +0100 Message-Id: <20201103143528.22780-6-jgross@suse.com> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20201103143528.22780-1-jgross@suse.com> References: <20201103143528.22780-1-jgross@suse.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org In order to avoid tight event channel related IRQ loops add a new framework of "late EOI" handling: the IRQ the event channel is bound to will be masked until the event has been handled and the related driver is capable to handle another event. The driver is responsible for unmasking the event channel via the new function xen_irq_lateeoi(). This is similar to binding an event channel to a threaded IRQ, but without having to structure the driver accordingly. In order to support a future special handling in case a rogue guest is sending lots of unsolicited events, add a flag to xen_irq_lateeoi() which can be set by the caller to indicate the event was a spurious one. This is part of XSA-332. This is upstream commit 54c9de89895e0a36047fcc4ae754ea5b8655fb9d Cc: stable@vger.kernel.org Reported-by: Julien Grall Signed-off-by: Juergen Gross Reviewed-by: Jan Beulich Reviewed-by: Stefano Stabellini Reviewed-by: Wei Liu --- drivers/xen/events/events_base.c | 151 +++++++++++++++++++++++++++---- include/xen/events.h | 29 +++++- 2 files changed, 159 insertions(+), 21 deletions(-) diff --git a/drivers/xen/events/events_base.c b/drivers/xen/events/events_base.c index e4d40dd513f5..2f076d6621b4 100644 --- a/drivers/xen/events/events_base.c +++ b/drivers/xen/events/events_base.c @@ -112,6 +112,7 @@ static bool (*pirq_needs_eoi)(unsigned irq); static struct irq_info *legacy_info_ptrs[NR_IRQS_LEGACY]; static struct irq_chip xen_dynamic_chip; +static struct irq_chip xen_lateeoi_chip; static struct irq_chip xen_percpu_chip; static struct irq_chip xen_pirq_chip; static void enable_dynirq(struct irq_data *data); @@ -404,6 +405,33 @@ void notify_remote_via_irq(int irq) } EXPORT_SYMBOL_GPL(notify_remote_via_irq); +static void xen_irq_lateeoi_locked(struct irq_info *info) +{ + evtchn_port_t evtchn; + + evtchn = info->evtchn; + if (!VALID_EVTCHN(evtchn)) + return; + + unmask_evtchn(evtchn); +} + +void xen_irq_lateeoi(unsigned int irq, unsigned int eoi_flags) +{ + struct irq_info *info; + unsigned long flags; + + read_lock_irqsave(&evtchn_rwlock, flags); + + info = info_for_irq(irq); + + if (info) + xen_irq_lateeoi_locked(info); + + read_unlock_irqrestore(&evtchn_rwlock, flags); +} +EXPORT_SYMBOL_GPL(xen_irq_lateeoi); + static void xen_irq_init(unsigned irq) { struct irq_info *info; @@ -875,7 +903,7 @@ int xen_pirq_from_irq(unsigned irq) } EXPORT_SYMBOL_GPL(xen_pirq_from_irq); -int bind_evtchn_to_irq(unsigned int evtchn) +static int bind_evtchn_to_irq_chip(evtchn_port_t evtchn, struct irq_chip *chip) { int irq; int ret; @@ -892,7 +920,7 @@ int bind_evtchn_to_irq(unsigned int evtchn) if (irq < 0) goto out; - irq_set_chip_and_handler_name(irq, &xen_dynamic_chip, + irq_set_chip_and_handler_name(irq, chip, handle_edge_irq, "event"); ret = xen_irq_info_evtchn_setup(irq, evtchn); @@ -913,8 +941,19 @@ int bind_evtchn_to_irq(unsigned int evtchn) return irq; } + +int bind_evtchn_to_irq(evtchn_port_t evtchn) +{ + return bind_evtchn_to_irq_chip(evtchn, &xen_dynamic_chip); +} EXPORT_SYMBOL_GPL(bind_evtchn_to_irq); +int bind_evtchn_to_irq_lateeoi(evtchn_port_t evtchn) +{ + return bind_evtchn_to_irq_chip(evtchn, &xen_lateeoi_chip); +} +EXPORT_SYMBOL_GPL(bind_evtchn_to_irq_lateeoi); + static int bind_ipi_to_irq(unsigned int ipi, unsigned int cpu) { struct evtchn_bind_ipi bind_ipi; @@ -956,8 +995,9 @@ static int bind_ipi_to_irq(unsigned int ipi, unsigned int cpu) return irq; } -int bind_interdomain_evtchn_to_irq(unsigned int remote_domain, - unsigned int remote_port) +static int bind_interdomain_evtchn_to_irq_chip(unsigned int remote_domain, + evtchn_port_t remote_port, + struct irq_chip *chip) { struct evtchn_bind_interdomain bind_interdomain; int err; @@ -968,10 +1008,26 @@ int bind_interdomain_evtchn_to_irq(unsigned int remote_domain, err = HYPERVISOR_event_channel_op(EVTCHNOP_bind_interdomain, &bind_interdomain); - return err ? : bind_evtchn_to_irq(bind_interdomain.local_port); + return err ? : bind_evtchn_to_irq_chip(bind_interdomain.local_port, + chip); +} + +int bind_interdomain_evtchn_to_irq(unsigned int remote_domain, + evtchn_port_t remote_port) +{ + return bind_interdomain_evtchn_to_irq_chip(remote_domain, remote_port, + &xen_dynamic_chip); } EXPORT_SYMBOL_GPL(bind_interdomain_evtchn_to_irq); +int bind_interdomain_evtchn_to_irq_lateeoi(unsigned int remote_domain, + evtchn_port_t remote_port) +{ + return bind_interdomain_evtchn_to_irq_chip(remote_domain, remote_port, + &xen_lateeoi_chip); +} +EXPORT_SYMBOL_GPL(bind_interdomain_evtchn_to_irq_lateeoi); + static int find_virq(unsigned int virq, unsigned int cpu) { struct evtchn_status status; @@ -1067,14 +1123,15 @@ static void unbind_from_irq(unsigned int irq) mutex_unlock(&irq_mapping_update_lock); } -int bind_evtchn_to_irqhandler(unsigned int evtchn, - irq_handler_t handler, - unsigned long irqflags, - const char *devname, void *dev_id) +static int bind_evtchn_to_irqhandler_chip(evtchn_port_t evtchn, + irq_handler_t handler, + unsigned long irqflags, + const char *devname, void *dev_id, + struct irq_chip *chip) { int irq, retval; - irq = bind_evtchn_to_irq(evtchn); + irq = bind_evtchn_to_irq_chip(evtchn, chip); if (irq < 0) return irq; retval = request_irq(irq, handler, irqflags, devname, dev_id); @@ -1085,18 +1142,38 @@ int bind_evtchn_to_irqhandler(unsigned int evtchn, return irq; } + +int bind_evtchn_to_irqhandler(evtchn_port_t evtchn, + irq_handler_t handler, + unsigned long irqflags, + const char *devname, void *dev_id) +{ + return bind_evtchn_to_irqhandler_chip(evtchn, handler, irqflags, + devname, dev_id, + &xen_dynamic_chip); +} EXPORT_SYMBOL_GPL(bind_evtchn_to_irqhandler); -int bind_interdomain_evtchn_to_irqhandler(unsigned int remote_domain, - unsigned int remote_port, - irq_handler_t handler, - unsigned long irqflags, - const char *devname, - void *dev_id) +int bind_evtchn_to_irqhandler_lateeoi(evtchn_port_t evtchn, + irq_handler_t handler, + unsigned long irqflags, + const char *devname, void *dev_id) +{ + return bind_evtchn_to_irqhandler_chip(evtchn, handler, irqflags, + devname, dev_id, + &xen_lateeoi_chip); +} +EXPORT_SYMBOL_GPL(bind_evtchn_to_irqhandler_lateeoi); + +static int bind_interdomain_evtchn_to_irqhandler_chip( + unsigned int remote_domain, evtchn_port_t remote_port, + irq_handler_t handler, unsigned long irqflags, + const char *devname, void *dev_id, struct irq_chip *chip) { int irq, retval; - irq = bind_interdomain_evtchn_to_irq(remote_domain, remote_port); + irq = bind_interdomain_evtchn_to_irq_chip(remote_domain, remote_port, + chip); if (irq < 0) return irq; @@ -1108,8 +1185,33 @@ int bind_interdomain_evtchn_to_irqhandler(unsigned int remote_domain, return irq; } + +int bind_interdomain_evtchn_to_irqhandler(unsigned int remote_domain, + evtchn_port_t remote_port, + irq_handler_t handler, + unsigned long irqflags, + const char *devname, + void *dev_id) +{ + return bind_interdomain_evtchn_to_irqhandler_chip(remote_domain, + remote_port, handler, irqflags, devname, + dev_id, &xen_dynamic_chip); +} EXPORT_SYMBOL_GPL(bind_interdomain_evtchn_to_irqhandler); +int bind_interdomain_evtchn_to_irqhandler_lateeoi(unsigned int remote_domain, + evtchn_port_t remote_port, + irq_handler_t handler, + unsigned long irqflags, + const char *devname, + void *dev_id) +{ + return bind_interdomain_evtchn_to_irqhandler_chip(remote_domain, + remote_port, handler, irqflags, devname, + dev_id, &xen_lateeoi_chip); +} +EXPORT_SYMBOL_GPL(bind_interdomain_evtchn_to_irqhandler_lateeoi); + int bind_virq_to_irqhandler(unsigned int virq, unsigned int cpu, irq_handler_t handler, unsigned long irqflags, const char *devname, void *dev_id) @@ -1643,6 +1745,21 @@ static struct irq_chip xen_dynamic_chip __read_mostly = { .irq_retrigger = retrigger_dynirq, }; +static struct irq_chip xen_lateeoi_chip __read_mostly = { + /* The chip name needs to contain "xen-dyn" for irqbalance to work. */ + .name = "xen-dyn-lateeoi", + + .irq_disable = disable_dynirq, + .irq_mask = disable_dynirq, + .irq_unmask = enable_dynirq, + + .irq_ack = mask_ack_dynirq, + .irq_mask_ack = mask_ack_dynirq, + + .irq_set_affinity = set_affinity_irq, + .irq_retrigger = retrigger_dynirq, +}; + static struct irq_chip xen_pirq_chip __read_mostly = { .name = "xen-pirq", diff --git a/include/xen/events.h b/include/xen/events.h index 88da2abaf535..ad0c61cf399b 100644 --- a/include/xen/events.h +++ b/include/xen/events.h @@ -12,11 +12,16 @@ unsigned xen_evtchn_nr_channels(void); -int bind_evtchn_to_irq(unsigned int evtchn); -int bind_evtchn_to_irqhandler(unsigned int evtchn, +int bind_evtchn_to_irq(evtchn_port_t evtchn); +int bind_evtchn_to_irq_lateeoi(evtchn_port_t evtchn); +int bind_evtchn_to_irqhandler(evtchn_port_t evtchn, irq_handler_t handler, unsigned long irqflags, const char *devname, void *dev_id); +int bind_evtchn_to_irqhandler_lateeoi(evtchn_port_t evtchn, + irq_handler_t handler, + unsigned long irqflags, const char *devname, + void *dev_id); int bind_virq_to_irq(unsigned int virq, unsigned int cpu, bool percpu); int bind_virq_to_irqhandler(unsigned int virq, unsigned int cpu, irq_handler_t handler, @@ -29,13 +34,21 @@ int bind_ipi_to_irqhandler(enum ipi_vector ipi, const char *devname, void *dev_id); int bind_interdomain_evtchn_to_irq(unsigned int remote_domain, - unsigned int remote_port); + evtchn_port_t remote_port); +int bind_interdomain_evtchn_to_irq_lateeoi(unsigned int remote_domain, + evtchn_port_t remote_port); int bind_interdomain_evtchn_to_irqhandler(unsigned int remote_domain, - unsigned int remote_port, + evtchn_port_t remote_port, irq_handler_t handler, unsigned long irqflags, const char *devname, void *dev_id); +int bind_interdomain_evtchn_to_irqhandler_lateeoi(unsigned int remote_domain, + evtchn_port_t remote_port, + irq_handler_t handler, + unsigned long irqflags, + const char *devname, + void *dev_id); /* * Common unbind function for all event sources. Takes IRQ to unbind from. @@ -44,6 +57,14 @@ int bind_interdomain_evtchn_to_irqhandler(unsigned int remote_domain, */ void unbind_from_irqhandler(unsigned int irq, void *dev_id); +/* + * Send late EOI for an IRQ bound to an event channel via one of the *_lateeoi + * functions above. + */ +void xen_irq_lateeoi(unsigned int irq, unsigned int eoi_flags); +/* Signal an event was spurious, i.e. there was no action resulting from it. */ +#define XEN_EOI_FLAG_SPURIOUS 0x00000001 + #define XEN_IRQ_PRIORITY_MAX EVTCHN_FIFO_PRIORITY_MAX #define XEN_IRQ_PRIORITY_DEFAULT EVTCHN_FIFO_PRIORITY_DEFAULT #define XEN_IRQ_PRIORITY_MIN EVTCHN_FIFO_PRIORITY_MIN From patchwork Tue Nov 3 14:35:21 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: =?utf-8?b?SsO8cmdlbiBHcm/Dnw==?= X-Patchwork-Id: 317262 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=-12.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT 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 06E9AC55179 for ; Tue, 3 Nov 2020 14:35:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id ACBE722453 for ; Tue, 3 Nov 2020 14:35:54 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=suse.com header.i=@suse.com header.b="BqGFFiKf" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727186AbgKCOfy (ORCPT ); Tue, 3 Nov 2020 09:35:54 -0500 Received: from mx2.suse.de ([195.135.220.15]:47280 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728192AbgKCOfc (ORCPT ); Tue, 3 Nov 2020 09:35:32 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1604414129; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=JZbGa3Mh+L8CuOVpxF3A7AtfHAvFGUAq/5+GVjl1tN4=; b=BqGFFiKf+1KCBs93TRSIMvNNBZbQbv6v4Lt4U7teIEazreJ9AM5HZ6kEceMYwfowdeoQSt /v72KsUb/dDr/0O/j1C8hs0SrDElwY8gti0uZYl0pC7ap43mpvyiem0DlC8T8FEi90qdZX N2jm9pS1ZI9yfZWoVe/s5Wd58V4XdgU= Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 57ADCB2A7 for ; Tue, 3 Nov 2020 14:35:29 +0000 (UTC) From: Juergen Gross To: stable@vger.kernel.org Subject: [PATCH v2 06/13] xen/blkback: use lateeoi irq binding Date: Tue, 3 Nov 2020 15:35:21 +0100 Message-Id: <20201103143528.22780-7-jgross@suse.com> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20201103143528.22780-1-jgross@suse.com> References: <20201103143528.22780-1-jgross@suse.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org In order to reduce the chance for the system becoming unresponsive due to event storms triggered by a misbehaving blkfront use the lateeoi irq binding for blkback and unmask the event channel only after processing all pending requests. As the thread processing requests is used to do purging work in regular intervals an EOI may be sent only after having received an event. If there was no pending I/O request flag the EOI as spurious. This is part of XSA-332. This is upstream commit 01263a1fabe30b4d542f34c7e2364a22587ddaf2 Cc: stable@vger.kernel.org Reported-by: Julien Grall Signed-off-by: Juergen Gross Reviewed-by: Jan Beulich Reviewed-by: Wei Liu --- drivers/block/xen-blkback/blkback.c | 22 +++++++++++++++++----- drivers/block/xen-blkback/xenbus.c | 5 ++--- 2 files changed, 19 insertions(+), 8 deletions(-) diff --git a/drivers/block/xen-blkback/blkback.c b/drivers/block/xen-blkback/blkback.c index a700e525535c..4f643a87f9c7 100644 --- a/drivers/block/xen-blkback/blkback.c +++ b/drivers/block/xen-blkback/blkback.c @@ -183,7 +183,7 @@ static inline void shrink_free_pagepool(struct xen_blkif_ring *ring, int num) #define vaddr(page) ((unsigned long)pfn_to_kaddr(page_to_pfn(page))) -static int do_block_io_op(struct xen_blkif_ring *ring); +static int do_block_io_op(struct xen_blkif_ring *ring, unsigned int *eoi_flags); static int dispatch_rw_block_io(struct xen_blkif_ring *ring, struct blkif_request *req, struct pending_req *pending_req); @@ -608,6 +608,8 @@ int xen_blkif_schedule(void *arg) struct xen_vbd *vbd = &blkif->vbd; unsigned long timeout; int ret; + bool do_eoi; + unsigned int eoi_flags = XEN_EOI_FLAG_SPURIOUS; set_freezable(); while (!kthread_should_stop()) { @@ -632,16 +634,23 @@ int xen_blkif_schedule(void *arg) if (timeout == 0) goto purge_gnt_list; + do_eoi = ring->waiting_reqs; + ring->waiting_reqs = 0; smp_mb(); /* clear flag *before* checking for work */ - ret = do_block_io_op(ring); + ret = do_block_io_op(ring, &eoi_flags); if (ret > 0) ring->waiting_reqs = 1; if (ret == -EACCES) wait_event_interruptible(ring->shutdown_wq, kthread_should_stop()); + if (do_eoi && !ring->waiting_reqs) { + xen_irq_lateeoi(ring->irq, eoi_flags); + eoi_flags |= XEN_EOI_FLAG_SPURIOUS; + } + purge_gnt_list: if (blkif->vbd.feature_gnt_persistent && time_after(jiffies, ring->next_lru)) { @@ -1117,7 +1126,7 @@ static void end_block_io_op(struct bio *bio) * and transmute it to the block API to hand it over to the proper block disk. */ static int -__do_block_io_op(struct xen_blkif_ring *ring) +__do_block_io_op(struct xen_blkif_ring *ring, unsigned int *eoi_flags) { union blkif_back_rings *blk_rings = &ring->blk_rings; struct blkif_request req; @@ -1140,6 +1149,9 @@ __do_block_io_op(struct xen_blkif_ring *ring) if (RING_REQUEST_CONS_OVERFLOW(&blk_rings->common, rc)) break; + /* We've seen a request, so clear spurious eoi flag. */ + *eoi_flags &= ~XEN_EOI_FLAG_SPURIOUS; + if (kthread_should_stop()) { more_to_do = 1; break; @@ -1198,13 +1210,13 @@ __do_block_io_op(struct xen_blkif_ring *ring) } static int -do_block_io_op(struct xen_blkif_ring *ring) +do_block_io_op(struct xen_blkif_ring *ring, unsigned int *eoi_flags) { union blkif_back_rings *blk_rings = &ring->blk_rings; int more_to_do; do { - more_to_do = __do_block_io_op(ring); + more_to_do = __do_block_io_op(ring, eoi_flags); if (more_to_do) break; diff --git a/drivers/block/xen-blkback/xenbus.c b/drivers/block/xen-blkback/xenbus.c index 1d1f86657967..702ebfc4face 100644 --- a/drivers/block/xen-blkback/xenbus.c +++ b/drivers/block/xen-blkback/xenbus.c @@ -236,9 +236,8 @@ static int xen_blkif_map(struct xen_blkif_ring *ring, grant_ref_t *gref, BUG(); } - err = bind_interdomain_evtchn_to_irqhandler(blkif->domid, evtchn, - xen_blkif_be_int, 0, - "blkif-backend", ring); + err = bind_interdomain_evtchn_to_irqhandler_lateeoi(blkif->domid, + evtchn, xen_blkif_be_int, 0, "blkif-backend", ring); if (err < 0) { xenbus_unmap_ring_vfree(blkif->be->dev, ring->blk_ring); ring->blk_rings.common.sring = NULL; From patchwork Tue Nov 3 14:35:22 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: =?utf-8?b?SsO8cmdlbiBHcm/Dnw==?= X-Patchwork-Id: 317263 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=-12.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT 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 1EE7EC2D0A3 for ; Tue, 3 Nov 2020 14:35:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AF86922370 for ; Tue, 3 Nov 2020 14:35:53 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=suse.com header.i=@suse.com header.b="L5mPlAil" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727323AbgKCOfx (ORCPT ); Tue, 3 Nov 2020 09:35:53 -0500 Received: from mx2.suse.de ([195.135.220.15]:47284 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728199AbgKCOfd (ORCPT ); Tue, 3 Nov 2020 09:35:33 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1604414129; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=LxbAfCJEI3uTWLzbBAtEO6QWYOJCDsfJ30Ersr2IcUk=; b=L5mPlAil1AaLC/vAIRBnTZiOP6zRZkjBuM2eRQ9zIsMU8rwnKS6O6+8Mc0YEZ+TtDJAKPE X+UG/IEuiRSJYrGGw6Y84znThus2W7RVe6Z3Dvml6Jni2us5sz8tQOR0ZeHklrB6mi4Byu Ry/yJuzVQ8sCUhgx6CrPpEcg6pR3cFY= Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 6D88CB2A8 for ; Tue, 3 Nov 2020 14:35:29 +0000 (UTC) From: Juergen Gross To: stable@vger.kernel.org Subject: [PATCH v2 07/13] xen/netback: use lateeoi irq binding Date: Tue, 3 Nov 2020 15:35:22 +0100 Message-Id: <20201103143528.22780-8-jgross@suse.com> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20201103143528.22780-1-jgross@suse.com> References: <20201103143528.22780-1-jgross@suse.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org In order to reduce the chance for the system becoming unresponsive due to event storms triggered by a misbehaving netfront use the lateeoi irq binding for netback and unmask the event channel only just before going to sleep waiting for new events. Make sure not to issue an EOI when none is pending by introducing an eoi_pending element to struct xenvif_queue. When no request has been consumed set the spurious flag when sending the EOI for an interrupt. This is part of XSA-332. This is upstream commit 23025393dbeb3b8b3b60ebfa724cdae384992e27 Cc: stable@vger.kernel.org Reported-by: Julien Grall Signed-off-by: Juergen Gross Reviewed-by: Jan Beulich Reviewed-by: Wei Liu --- drivers/net/xen-netback/common.h | 15 +++++++ drivers/net/xen-netback/interface.c | 61 ++++++++++++++++++++++++----- drivers/net/xen-netback/netback.c | 11 +++++- drivers/net/xen-netback/rx.c | 13 ++++-- 4 files changed, 86 insertions(+), 14 deletions(-) diff --git a/drivers/net/xen-netback/common.h b/drivers/net/xen-netback/common.h index 5b1d2e8402d9..347c796afd4e 100644 --- a/drivers/net/xen-netback/common.h +++ b/drivers/net/xen-netback/common.h @@ -140,6 +140,20 @@ struct xenvif_queue { /* Per-queue data for xenvif */ char name[QUEUE_NAME_SIZE]; /* DEVNAME-qN */ struct xenvif *vif; /* Parent VIF */ + /* + * TX/RX common EOI handling. + * When feature-split-event-channels = 0, interrupt handler sets + * NETBK_COMMON_EOI, otherwise NETBK_RX_EOI and NETBK_TX_EOI are set + * by the RX and TX interrupt handlers. + * RX and TX handler threads will issue an EOI when either + * NETBK_COMMON_EOI or their specific bits (NETBK_RX_EOI or + * NETBK_TX_EOI) are set and they will reset those bits. + */ + atomic_t eoi_pending; +#define NETBK_RX_EOI 0x01 +#define NETBK_TX_EOI 0x02 +#define NETBK_COMMON_EOI 0x04 + /* Use NAPI for guest TX */ struct napi_struct napi; /* When feature-split-event-channels = 0, tx_irq = rx_irq. */ @@ -356,6 +370,7 @@ int xenvif_dealloc_kthread(void *data); irqreturn_t xenvif_ctrl_irq_fn(int irq, void *data); +bool xenvif_have_rx_work(struct xenvif_queue *queue, bool test_kthread); void xenvif_rx_action(struct xenvif_queue *queue); void xenvif_rx_queue_tail(struct xenvif_queue *queue, struct sk_buff *skb); diff --git a/drivers/net/xen-netback/interface.c b/drivers/net/xen-netback/interface.c index 46008f284550..e61073c75142 100644 --- a/drivers/net/xen-netback/interface.c +++ b/drivers/net/xen-netback/interface.c @@ -76,12 +76,28 @@ int xenvif_schedulable(struct xenvif *vif) !vif->disabled; } +static bool xenvif_handle_tx_interrupt(struct xenvif_queue *queue) +{ + bool rc; + + rc = RING_HAS_UNCONSUMED_REQUESTS(&queue->tx); + if (rc) + napi_schedule(&queue->napi); + return rc; +} + static irqreturn_t xenvif_tx_interrupt(int irq, void *dev_id) { struct xenvif_queue *queue = dev_id; + int old; - if (RING_HAS_UNCONSUMED_REQUESTS(&queue->tx)) - napi_schedule(&queue->napi); + old = atomic_fetch_or(NETBK_TX_EOI, &queue->eoi_pending); + WARN(old & NETBK_TX_EOI, "Interrupt while EOI pending\n"); + + if (!xenvif_handle_tx_interrupt(queue)) { + atomic_andnot(NETBK_TX_EOI, &queue->eoi_pending); + xen_irq_lateeoi(irq, XEN_EOI_FLAG_SPURIOUS); + } return IRQ_HANDLED; } @@ -115,19 +131,46 @@ static int xenvif_poll(struct napi_struct *napi, int budget) return work_done; } +static bool xenvif_handle_rx_interrupt(struct xenvif_queue *queue) +{ + bool rc; + + rc = xenvif_have_rx_work(queue, false); + if (rc) + xenvif_kick_thread(queue); + return rc; +} + static irqreturn_t xenvif_rx_interrupt(int irq, void *dev_id) { struct xenvif_queue *queue = dev_id; + int old; - xenvif_kick_thread(queue); + old = atomic_fetch_or(NETBK_RX_EOI, &queue->eoi_pending); + WARN(old & NETBK_RX_EOI, "Interrupt while EOI pending\n"); + + if (!xenvif_handle_rx_interrupt(queue)) { + atomic_andnot(NETBK_RX_EOI, &queue->eoi_pending); + xen_irq_lateeoi(irq, XEN_EOI_FLAG_SPURIOUS); + } return IRQ_HANDLED; } irqreturn_t xenvif_interrupt(int irq, void *dev_id) { - xenvif_tx_interrupt(irq, dev_id); - xenvif_rx_interrupt(irq, dev_id); + struct xenvif_queue *queue = dev_id; + int old; + + old = atomic_fetch_or(NETBK_COMMON_EOI, &queue->eoi_pending); + WARN(old, "Interrupt while EOI pending\n"); + + /* Use bitwise or as we need to call both functions. */ + if ((!xenvif_handle_tx_interrupt(queue) | + !xenvif_handle_rx_interrupt(queue))) { + atomic_andnot(NETBK_COMMON_EOI, &queue->eoi_pending); + xen_irq_lateeoi(irq, XEN_EOI_FLAG_SPURIOUS); + } return IRQ_HANDLED; } @@ -583,7 +626,7 @@ int xenvif_connect_ctrl(struct xenvif *vif, grant_ref_t ring_ref, shared = (struct xen_netif_ctrl_sring *)addr; BACK_RING_INIT(&vif->ctrl, shared, XEN_PAGE_SIZE); - err = bind_interdomain_evtchn_to_irq(vif->domid, evtchn); + err = bind_interdomain_evtchn_to_irq_lateeoi(vif->domid, evtchn); if (err < 0) goto err_unmap; @@ -641,7 +684,7 @@ int xenvif_connect_data(struct xenvif_queue *queue, if (tx_evtchn == rx_evtchn) { /* feature-split-event-channels == 0 */ - err = bind_interdomain_evtchn_to_irqhandler( + err = bind_interdomain_evtchn_to_irqhandler_lateeoi( queue->vif->domid, tx_evtchn, xenvif_interrupt, 0, queue->name, queue); if (err < 0) @@ -652,7 +695,7 @@ int xenvif_connect_data(struct xenvif_queue *queue, /* feature-split-event-channels == 1 */ snprintf(queue->tx_irq_name, sizeof(queue->tx_irq_name), "%s-tx", queue->name); - err = bind_interdomain_evtchn_to_irqhandler( + err = bind_interdomain_evtchn_to_irqhandler_lateeoi( queue->vif->domid, tx_evtchn, xenvif_tx_interrupt, 0, queue->tx_irq_name, queue); if (err < 0) @@ -662,7 +705,7 @@ int xenvif_connect_data(struct xenvif_queue *queue, snprintf(queue->rx_irq_name, sizeof(queue->rx_irq_name), "%s-rx", queue->name); - err = bind_interdomain_evtchn_to_irqhandler( + err = bind_interdomain_evtchn_to_irqhandler_lateeoi( queue->vif->domid, rx_evtchn, xenvif_rx_interrupt, 0, queue->rx_irq_name, queue); if (err < 0) diff --git a/drivers/net/xen-netback/netback.c b/drivers/net/xen-netback/netback.c index a469fbe1abaf..fd2ac6cd0c69 100644 --- a/drivers/net/xen-netback/netback.c +++ b/drivers/net/xen-netback/netback.c @@ -162,6 +162,10 @@ void xenvif_napi_schedule_or_enable_events(struct xenvif_queue *queue) if (more_to_do) napi_schedule(&queue->napi); + else if (atomic_fetch_andnot(NETBK_TX_EOI | NETBK_COMMON_EOI, + &queue->eoi_pending) & + (NETBK_TX_EOI | NETBK_COMMON_EOI)) + xen_irq_lateeoi(queue->tx_irq, 0); } static void tx_add_credit(struct xenvif_queue *queue) @@ -1615,9 +1619,14 @@ static bool xenvif_ctrl_work_todo(struct xenvif *vif) irqreturn_t xenvif_ctrl_irq_fn(int irq, void *data) { struct xenvif *vif = data; + unsigned int eoi_flag = XEN_EOI_FLAG_SPURIOUS; - while (xenvif_ctrl_work_todo(vif)) + while (xenvif_ctrl_work_todo(vif)) { xenvif_ctrl_action(vif); + eoi_flag = 0; + } + + xen_irq_lateeoi(irq, eoi_flag); return IRQ_HANDLED; } diff --git a/drivers/net/xen-netback/rx.c b/drivers/net/xen-netback/rx.c index b1cf7c6f407a..f152246c7dfb 100644 --- a/drivers/net/xen-netback/rx.c +++ b/drivers/net/xen-netback/rx.c @@ -490,13 +490,13 @@ static bool xenvif_rx_queue_ready(struct xenvif_queue *queue) return queue->stalled && prod - cons >= 1; } -static bool xenvif_have_rx_work(struct xenvif_queue *queue) +bool xenvif_have_rx_work(struct xenvif_queue *queue, bool test_kthread) { return xenvif_rx_ring_slots_available(queue) || (queue->vif->stall_timeout && (xenvif_rx_queue_stalled(queue) || xenvif_rx_queue_ready(queue))) || - kthread_should_stop() || + (test_kthread && kthread_should_stop()) || queue->vif->disabled; } @@ -527,15 +527,20 @@ static void xenvif_wait_for_rx_work(struct xenvif_queue *queue) { DEFINE_WAIT(wait); - if (xenvif_have_rx_work(queue)) + if (xenvif_have_rx_work(queue, true)) return; for (;;) { long ret; prepare_to_wait(&queue->wq, &wait, TASK_INTERRUPTIBLE); - if (xenvif_have_rx_work(queue)) + if (xenvif_have_rx_work(queue, true)) break; + if (atomic_fetch_andnot(NETBK_RX_EOI | NETBK_COMMON_EOI, + &queue->eoi_pending) & + (NETBK_RX_EOI | NETBK_COMMON_EOI)) + xen_irq_lateeoi(queue->rx_irq, 0); + ret = schedule_timeout(xenvif_rx_queue_timeout(queue)); if (!ret) break; From patchwork Tue Nov 3 14:35:25 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: =?utf-8?b?SsO8cmdlbiBHcm/Dnw==?= X-Patchwork-Id: 317259 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=-12.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT 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 37DB5C5517A for ; Tue, 3 Nov 2020 14:35:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E0C8E2244C for ; Tue, 3 Nov 2020 14:35:54 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=suse.com header.i=@suse.com header.b="Sqkx4sgN" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728072AbgKCOfx (ORCPT ); Tue, 3 Nov 2020 09:35:53 -0500 Received: from mx2.suse.de ([195.135.220.15]:47294 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728248AbgKCOfc (ORCPT ); Tue, 3 Nov 2020 09:35:32 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1604414129; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=BoXo0vU/l+clTxUbs4bEpnnnJm2Z50z4yZ9YTr6f2A0=; b=Sqkx4sgN5a6cst54NDizeRkojESCMDDyE+cQl0pcP+t2fZTivRjlGc0NwTAvbyhNAyUUti Cux9QcpRSxExQ4nQMeu922ho99wPYXqplw+vfRlHHBFiVvz20YJLRIBd0mmeXYaFQ6fbm3 5W7YWeJgHXFkEh/BdC9FtGihZ+Qu+iI= Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id AFB56B2AB for ; Tue, 3 Nov 2020 14:35:29 +0000 (UTC) From: Juergen Gross To: stable@vger.kernel.org Subject: [PATCH v2 10/13] xen/events: switch user event channels to lateeoi model Date: Tue, 3 Nov 2020 15:35:25 +0100 Message-Id: <20201103143528.22780-11-jgross@suse.com> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20201103143528.22780-1-jgross@suse.com> References: <20201103143528.22780-1-jgross@suse.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org Instead of disabling the irq when an event is received and enabling it again when handled by the user process use the lateeoi model. This is part of XSA-332. This is upstream commit c44b849cee8c3ac587da3b0980e01f77500d158c Cc: stable@vger.kernel.org Reported-by: Julien Grall Signed-off-by: Juergen Gross Tested-by: Stefano Stabellini Reviewed-by: Stefano Stabellini Reviewed-by: Jan Beulich Reviewed-by: Wei Liu --- drivers/xen/evtchn.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/drivers/xen/evtchn.c b/drivers/xen/evtchn.c index e8c7f09d01be..bcf0b1e60f2c 100644 --- a/drivers/xen/evtchn.c +++ b/drivers/xen/evtchn.c @@ -178,7 +178,6 @@ static irqreturn_t evtchn_interrupt(int irq, void *data) "Interrupt for port %d, but apparently not enabled; per-user %p\n", evtchn->port, u); - disable_irq_nosync(irq); evtchn->enabled = false; spin_lock(&u->ring_prod_lock); @@ -304,7 +303,7 @@ static ssize_t evtchn_write(struct file *file, const char __user *buf, evtchn = find_evtchn(u, port); if (evtchn && !evtchn->enabled) { evtchn->enabled = true; - enable_irq(irq_from_evtchn(port)); + xen_irq_lateeoi(irq_from_evtchn(port), 0); } } @@ -404,8 +403,8 @@ static int evtchn_bind_to_user(struct per_user_data *u, int port) if (rc < 0) goto err; - rc = bind_evtchn_to_irqhandler(port, evtchn_interrupt, 0, - u->name, evtchn); + rc = bind_evtchn_to_irqhandler_lateeoi(port, evtchn_interrupt, 0, + u->name, evtchn); if (rc < 0) goto err; From patchwork Tue Nov 3 14:35:26 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: =?utf-8?b?SsO8cmdlbiBHcm/Dnw==?= X-Patchwork-Id: 317261 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=-12.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT 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 6B274C56202 for ; Tue, 3 Nov 2020 14:35:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2518E223AC for ; Tue, 3 Nov 2020 14:35:55 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=suse.com header.i=@suse.com header.b="MYu/Rtt3" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728106AbgKCOfy (ORCPT ); Tue, 3 Nov 2020 09:35:54 -0500 Received: from mx2.suse.de ([195.135.220.15]:47298 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728256AbgKCOfc (ORCPT ); Tue, 3 Nov 2020 09:35:32 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1604414130; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=A6DblSDuoyZCKG+RlP90WV3mavoHS83Eo9uEYB8RoOo=; b=MYu/Rtt3FGFpjWn96fxWaWuNAo/h/KN7fDIzQJj4JSyhOp6SMqhZXvUYoYOzojW+Zixl+V yAKr3NooFVvU3ym0LYghuymmjI4dQEl6wNYzfB4FB6jX8mGT5j8/mxaKLEMn7iFVhe8hqV LhKCwOpLPTwLHpaNmWNEyPW5D2Q0clY= Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id D9EBDB2AC for ; Tue, 3 Nov 2020 14:35:29 +0000 (UTC) From: Juergen Gross To: stable@vger.kernel.org Subject: [PATCH v2 11/13] xen/events: use a common cpu hotplug hook for event channels Date: Tue, 3 Nov 2020 15:35:26 +0100 Message-Id: <20201103143528.22780-12-jgross@suse.com> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20201103143528.22780-1-jgross@suse.com> References: <20201103143528.22780-1-jgross@suse.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org Today only fifo event channels have a cpu hotplug callback. In order to prepare for more percpu (de)init work move that callback into events_base.c and add percpu_init() and percpu_deinit() hooks to struct evtchn_ops. This is part of XSA-332. This is upstream commit 7beb290caa2adb0a399e735a1e175db9aae0523a Cc: stable@vger.kernel.org Signed-off-by: Juergen Gross Reviewed-by: Jan Beulich Reviewed-by: Wei Liu --- drivers/xen/events/events_base.c | 25 ++++++++++++++++++ drivers/xen/events/events_fifo.c | 39 ++++++++++++++-------------- drivers/xen/events/events_internal.h | 3 +++ 3 files changed, 47 insertions(+), 20 deletions(-) diff --git a/drivers/xen/events/events_base.c b/drivers/xen/events/events_base.c index 2f076d6621b4..afcf2bf9845e 100644 --- a/drivers/xen/events/events_base.c +++ b/drivers/xen/events/events_base.c @@ -33,6 +33,7 @@ #include #include #include +#include #ifdef CONFIG_X86 #include @@ -1833,6 +1834,26 @@ void xen_callback_vector(void) {} static bool fifo_events = true; module_param(fifo_events, bool, 0); +static int xen_evtchn_cpu_prepare(unsigned int cpu) +{ + int ret = 0; + + if (evtchn_ops->percpu_init) + ret = evtchn_ops->percpu_init(cpu); + + return ret; +} + +static int xen_evtchn_cpu_dead(unsigned int cpu) +{ + int ret = 0; + + if (evtchn_ops->percpu_deinit) + ret = evtchn_ops->percpu_deinit(cpu); + + return ret; +} + void __init xen_init_IRQ(void) { int ret = -EINVAL; @@ -1842,6 +1863,10 @@ void __init xen_init_IRQ(void) if (ret < 0) xen_evtchn_2l_init(); + cpuhp_setup_state_nocalls(CPUHP_XEN_EVTCHN_PREPARE, + "CPUHP_XEN_EVTCHN_PREPARE", + xen_evtchn_cpu_prepare, xen_evtchn_cpu_dead); + evtchn_to_irq = kcalloc(EVTCHN_ROW(xen_evtchn_max_channels()), sizeof(*evtchn_to_irq), GFP_KERNEL); BUG_ON(!evtchn_to_irq); diff --git a/drivers/xen/events/events_fifo.c b/drivers/xen/events/events_fifo.c index 970a5eb6dca4..2b98cdebacd6 100644 --- a/drivers/xen/events/events_fifo.c +++ b/drivers/xen/events/events_fifo.c @@ -386,21 +386,6 @@ static void evtchn_fifo_resume(void) event_array_pages = 0; } -static const struct evtchn_ops evtchn_ops_fifo = { - .max_channels = evtchn_fifo_max_channels, - .nr_channels = evtchn_fifo_nr_channels, - .setup = evtchn_fifo_setup, - .bind_to_cpu = evtchn_fifo_bind_to_cpu, - .clear_pending = evtchn_fifo_clear_pending, - .set_pending = evtchn_fifo_set_pending, - .is_pending = evtchn_fifo_is_pending, - .test_and_set_mask = evtchn_fifo_test_and_set_mask, - .mask = evtchn_fifo_mask, - .unmask = evtchn_fifo_unmask, - .handle_events = evtchn_fifo_handle_events, - .resume = evtchn_fifo_resume, -}; - static int evtchn_fifo_alloc_control_block(unsigned cpu) { void *control_block = NULL; @@ -423,19 +408,36 @@ static int evtchn_fifo_alloc_control_block(unsigned cpu) return ret; } -static int xen_evtchn_cpu_prepare(unsigned int cpu) +static int evtchn_fifo_percpu_init(unsigned int cpu) { if (!per_cpu(cpu_control_block, cpu)) return evtchn_fifo_alloc_control_block(cpu); return 0; } -static int xen_evtchn_cpu_dead(unsigned int cpu) +static int evtchn_fifo_percpu_deinit(unsigned int cpu) { __evtchn_fifo_handle_events(cpu, true); return 0; } +static const struct evtchn_ops evtchn_ops_fifo = { + .max_channels = evtchn_fifo_max_channels, + .nr_channels = evtchn_fifo_nr_channels, + .setup = evtchn_fifo_setup, + .bind_to_cpu = evtchn_fifo_bind_to_cpu, + .clear_pending = evtchn_fifo_clear_pending, + .set_pending = evtchn_fifo_set_pending, + .is_pending = evtchn_fifo_is_pending, + .test_and_set_mask = evtchn_fifo_test_and_set_mask, + .mask = evtchn_fifo_mask, + .unmask = evtchn_fifo_unmask, + .handle_events = evtchn_fifo_handle_events, + .resume = evtchn_fifo_resume, + .percpu_init = evtchn_fifo_percpu_init, + .percpu_deinit = evtchn_fifo_percpu_deinit, +}; + int __init xen_evtchn_fifo_init(void) { int cpu = get_cpu(); @@ -449,9 +451,6 @@ int __init xen_evtchn_fifo_init(void) evtchn_ops = &evtchn_ops_fifo; - cpuhp_setup_state_nocalls(CPUHP_XEN_EVTCHN_PREPARE, - "CPUHP_XEN_EVTCHN_PREPARE", - xen_evtchn_cpu_prepare, xen_evtchn_cpu_dead); out: put_cpu(); return ret; diff --git a/drivers/xen/events/events_internal.h b/drivers/xen/events/events_internal.h index 50c2050a1e32..980a56d51e4c 100644 --- a/drivers/xen/events/events_internal.h +++ b/drivers/xen/events/events_internal.h @@ -71,6 +71,9 @@ struct evtchn_ops { void (*handle_events)(unsigned cpu); void (*resume)(void); + + int (*percpu_init)(unsigned int cpu); + int (*percpu_deinit)(unsigned int cpu); }; extern const struct evtchn_ops *evtchn_ops;