From patchwork Fri Jul 9 13:18:29 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 471818 Delivered-To: patch@linaro.org Received: by 2002:a02:c94a:0:0:0:0:0 with SMTP id u10csp291725jao; Fri, 9 Jul 2021 06:18:49 -0700 (PDT) X-Google-Smtp-Source: ABdhPJy5iyGtwDwOumFwn9cKIwnVPa4fcdxAT7cM2M7T6HGs+9ne4I0ikWWRmvD2Ak+Y7w78TiLX X-Received: by 2002:a05:6602:134f:: with SMTP id i15mr28796990iov.143.1625836729681; Fri, 09 Jul 2021 06:18:49 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1625836729; cv=none; d=google.com; s=arc-20160816; b=UabsiEeOXHgEact9lvMyn7IQMHso4Kc5xL1y2KlmAjcs1dClZ2cdD1m1iX8zJoekYr S1hXLG3n6S8eHPnZdgoirXppzP2u2jFv+rtoWShfkMylKCJv8+owsyE8xVcnMjZljoVW wrtEaEBkmpztyDUJYkA0eL3gQLpRkGGIsPLAUbNmL/bVvGiqc3M8Ap8gSxrjnlhoekJQ mPat5zJBoq6EyciJFRTRFXAyXBZtem1XRx9weuqLyKcHxBsA99RCXy2mDk8Y8op09qxR 9O7C7mcwGe8iQoSw8WsSG7hbLtp5I7Myw1qI1yelQSw/Qp46VQRrqrhsol2NfjFTVpPh kTwg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :user-agent:references:in-reply-to:message-id:date:subject:cc:to :from:dkim-signature; bh=i8O+yia/vKWDwgNeF62Zp+m+kHt8q6PtntnJmKkPEC8=; b=ibBtehyTb9qIUgS9tR4KQzstF1hSDa+c8Svb0QPLwknF0t6aWKwCFLp1d92DtjcKWu zPThiBe/aayUi1RUwLv+54EXYbKs67o4is5KzHqXd4hX0BpZUTdfERk7ov9RZjKzpAkD kT9Q74VBtlN3aC4hv0GSXjHPlEzpmFM/XAwf75PGL7/vV34YKj+QyD96uL5svHD3RJmN aeOMta+/JNLbo7Cm+nBw7AyY4T/5wyc5vl2pksvo2WMb6U/WcqMENTI0VBib7BnJw8rQ TJ4CFom8ybIp4i0Oi+ZFjQpVBAVWWB8JjOM/RQQj2PHKSXSCnuaJzCT2WRFBlnw5kCeq vo5g== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@linuxfoundation.org header.s=korg header.b="mf/HRz7Z"; spf=pass (google.com: domain of stable-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=stable-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=linuxfoundation.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [23.128.96.18]) by mx.google.com with ESMTP id y7si6354360ilu.160.2021.07.09.06.18.49; Fri, 09 Jul 2021 06:18:49 -0700 (PDT) Received-SPF: pass (google.com: domain of stable-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; dkim=pass header.i=@linuxfoundation.org header.s=korg header.b="mf/HRz7Z"; spf=pass (google.com: domain of stable-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=stable-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=linuxfoundation.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231753AbhGINVb (ORCPT + 12 others); Fri, 9 Jul 2021 09:21:31 -0400 Received: from mail.kernel.org ([198.145.29.99]:51616 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231917AbhGINVa (ORCPT ); Fri, 9 Jul 2021 09:21:30 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id BBF0E61357; Fri, 9 Jul 2021 13:18:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1625836727; bh=PMRTvEShQzEn2+bkr+fk5C8BpeD20RIjfulk2Dc2K9s=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=mf/HRz7Z9+fhwV81c7umMpr5UdrhCxe26GNL4oSluWsmOvC95GflZOU9/bPOUeaeV l7jye7BFRHMpt/Tud3LBTYZO1BdY7vFHaV8PeG2AE0zuwLnXUNxFcb2S6+BKOklrMS 0ydmvWSbTnLqmr/Z4oHipBrPdI5ruuib1o8K336Y= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Alex Shi , Michal Hocko , Hugh Dickins , Johannes Weiner , Vladimir Davydov , Andrew Morton , Linus Torvalds , Sasha Levin Subject: [PATCH 4.9 2/9] mm: add VM_WARN_ON_ONCE_PAGE() macro Date: Fri, 9 Jul 2021 15:18:29 +0200 Message-Id: <20210709131545.988367954@linuxfoundation.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210709131542.410636747@linuxfoundation.org> References: <20210709131542.410636747@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Alex Shi [ Upstream commit a4055888629bc0467d12d912cd7c90acdf3d9b12 part ] Add VM_WARN_ON_ONCE_PAGE() macro. Link: https://lkml.kernel.org/r/1604283436-18880-3-git-send-email-alex.shi@linux.alibaba.com Signed-off-by: Alex Shi Acked-by: Michal Hocko Acked-by: Hugh Dickins Acked-by: Johannes Weiner Cc: Vladimir Davydov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Note on stable backport: original commit was titled mm/memcg: warning on !memcg after readahead page charged which included uses of this macro in mm/memcontrol.c: here omitted. Signed-off-by: Hugh Dickins Signed-off-by: Sasha Levin --- include/linux/mmdebug.h | 13 +++++++++++++ 1 file changed, 13 insertions(+) -- 2.30.2 diff --git a/include/linux/mmdebug.h b/include/linux/mmdebug.h index deaba1cc3cfc..d1fb3bbff37a 100644 --- a/include/linux/mmdebug.h +++ b/include/linux/mmdebug.h @@ -36,6 +36,18 @@ void dump_mm(const struct mm_struct *mm); BUG(); \ } \ } while (0) +#define VM_WARN_ON_ONCE_PAGE(cond, page) ({ \ + static bool __section(".data.once") __warned; \ + int __ret_warn_once = !!(cond); \ + \ + if (unlikely(__ret_warn_once && !__warned)) { \ + dump_page(page, "VM_WARN_ON_ONCE_PAGE(" __stringify(cond)")");\ + __warned = true; \ + WARN_ON(1); \ + } \ + unlikely(__ret_warn_once); \ +}) + #define VM_WARN_ON(cond) (void)WARN_ON(cond) #define VM_WARN_ON_ONCE(cond) (void)WARN_ON_ONCE(cond) #define VM_WARN_ONCE(cond, format...) (void)WARN_ONCE(cond, format) @@ -47,6 +59,7 @@ void dump_mm(const struct mm_struct *mm); #define VM_BUG_ON_MM(cond, mm) VM_BUG_ON(cond) #define VM_WARN_ON(cond) BUILD_BUG_ON_INVALID(cond) #define VM_WARN_ON_ONCE(cond) BUILD_BUG_ON_INVALID(cond) +#define VM_WARN_ON_ONCE_PAGE(cond, page) BUILD_BUG_ON_INVALID(cond) #define VM_WARN_ONCE(cond, format...) BUILD_BUG_ON_INVALID(cond) #define VM_WARN(cond, format...) BUILD_BUG_ON_INVALID(cond) #endif From patchwork Fri Jul 9 13:18:30 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 472302 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=-19.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, 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 E31CDC11F68 for ; Fri, 9 Jul 2021 13:18:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CC280613C3 for ; Fri, 9 Jul 2021 13:18:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231948AbhGINVd (ORCPT ); Fri, 9 Jul 2021 09:21:33 -0400 Received: from mail.kernel.org ([198.145.29.99]:51660 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231937AbhGINVc (ORCPT ); Fri, 9 Jul 2021 09:21:32 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id E7215613C0; Fri, 9 Jul 2021 13:18:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1625836729; bh=bNSmK2y1b/XZc5iNW3WFr4NxiD4+Gxx1It4MXlJlVeg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=G3fA6IIc3xNR/Y0NMG+sjWK2zO5mcvpDrpQ3TbpAmiOJV2MsIDzUl+RNvzKVP+K79 IFiX3jm1BTzI3h0UiALZZ33h/f/7m/NV63/p1ERBM6Aw87+aexUW6GCPetJwwJTeMz dBEiLt3kSichzEP+m/kVjkUTCICOGpRDoLVHdih4= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Yang Shi , Zi Yan , "Kirill A. Shutemov" , Hugh Dickins , Alistair Popple , Jan Kara , Jue Wang , "Matthew Wilcox (Oracle)" , Miaohe Lin , Minchan Kim , Naoya Horiguchi , Oscar Salvador , Peter Xu , Ralph Campbell , Shakeel Butt , Wang Yugui , Andrew Morton , Linus Torvalds , Sasha Levin Subject: [PATCH 4.9 3/9] mm: thp: replace DEBUG_VM BUG with VM_WARN when unmap fails for split Date: Fri, 9 Jul 2021 15:18:30 +0200 Message-Id: <20210709131547.603899343@linuxfoundation.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210709131542.410636747@linuxfoundation.org> References: <20210709131542.410636747@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Yang Shi [ Upstream commit 504e070dc08f757bccaed6d05c0f53ecbfac8a23 ] When debugging the bug reported by Wang Yugui [1], try_to_unmap() may fail, but the first VM_BUG_ON_PAGE() just checks page_mapcount() however it may miss the failure when head page is unmapped but other subpage is mapped. Then the second DEBUG_VM BUG() that check total mapcount would catch it. This may incur some confusion. As this is not a fatal issue, so consolidate the two DEBUG_VM checks into one VM_WARN_ON_ONCE_PAGE(). [1] https://lore.kernel.org/linux-mm/20210412180659.B9E3.409509F4@e16-tech.com/ Link: https://lkml.kernel.org/r/d0f0db68-98b8-ebfb-16dc-f29df24cf012@google.com Signed-off-by: Yang Shi Reviewed-by: Zi Yan Acked-by: Kirill A. Shutemov Signed-off-by: Hugh Dickins Cc: Alistair Popple Cc: Jan Kara Cc: Jue Wang Cc: "Matthew Wilcox (Oracle)" Cc: Miaohe Lin Cc: Minchan Kim Cc: Naoya Horiguchi Cc: Oscar Salvador Cc: Peter Xu Cc: Ralph Campbell Cc: Shakeel Butt Cc: Wang Yugui Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Note on stable backport: fixed up variables, split_queue_lock, tree_lock in split_huge_page_to_list(); adapted to early version of unmap_page(). Signed-off-by: Hugh Dickins Signed-off-by: Sasha Levin --- mm/huge_memory.c | 29 ++++++++++------------------- 1 file changed, 10 insertions(+), 19 deletions(-) diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 14cd0ef33b62..177ca028b986 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -1891,7 +1891,7 @@ static void unmap_page(struct page *page) { enum ttu_flags ttu_flags = TTU_IGNORE_MLOCK | TTU_IGNORE_ACCESS | TTU_RMAP_LOCKED; - int i, ret; + int i; VM_BUG_ON_PAGE(!PageHead(page), page); @@ -1899,15 +1899,16 @@ static void unmap_page(struct page *page) ttu_flags |= TTU_MIGRATION; /* We only need TTU_SPLIT_HUGE_PMD once */ - ret = try_to_unmap(page, ttu_flags | TTU_SPLIT_HUGE_PMD); - for (i = 1; !ret && i < HPAGE_PMD_NR; i++) { + try_to_unmap(page, ttu_flags | TTU_SPLIT_HUGE_PMD); + for (i = 1; i < HPAGE_PMD_NR; i++) { /* Cut short if the page is unmapped */ if (page_count(page) == 1) return; - ret = try_to_unmap(page + i, ttu_flags); + try_to_unmap(page + i, ttu_flags); } - VM_BUG_ON_PAGE(ret, page + i - 1); + + VM_WARN_ON_ONCE_PAGE(page_mapped(page), page); } static void remap_page(struct page *page) @@ -2137,7 +2138,7 @@ int split_huge_page_to_list(struct page *page, struct list_head *list) struct pglist_data *pgdata = NODE_DATA(page_to_nid(head)); struct anon_vma *anon_vma = NULL; struct address_space *mapping = NULL; - int count, mapcount, extra_pins, ret; + int extra_pins, ret; bool mlocked; unsigned long flags; pgoff_t end; @@ -2200,7 +2201,6 @@ int split_huge_page_to_list(struct page *page, struct list_head *list) mlocked = PageMlocked(page); unmap_page(head); - VM_BUG_ON_PAGE(compound_mapcount(head), head); /* Make sure the page is not on per-CPU pagevec as it takes pin */ if (mlocked) @@ -2226,9 +2226,7 @@ int split_huge_page_to_list(struct page *page, struct list_head *list) /* Prevent deferred_split_scan() touching ->_refcount */ spin_lock(&pgdata->split_queue_lock); - count = page_count(head); - mapcount = total_mapcount(head); - if (!mapcount && page_ref_freeze(head, 1 + extra_pins)) { + if (page_ref_freeze(head, 1 + extra_pins)) { if (!list_empty(page_deferred_list(head))) { pgdata->split_queue_len--; list_del(page_deferred_list(head)); @@ -2239,16 +2237,9 @@ int split_huge_page_to_list(struct page *page, struct list_head *list) __split_huge_page(page, list, end, flags); ret = 0; } else { - if (IS_ENABLED(CONFIG_DEBUG_VM) && mapcount) { - pr_alert("total_mapcount: %u, page_count(): %u\n", - mapcount, count); - if (PageTail(page)) - dump_page(head, NULL); - dump_page(page, "total_mapcount(head) > 0"); - BUG(); - } spin_unlock(&pgdata->split_queue_lock); -fail: if (mapping) +fail: + if (mapping) spin_unlock(&mapping->tree_lock); spin_unlock_irqrestore(zone_lru_lock(page_zone(head)), flags); remap_page(head); From patchwork Fri Jul 9 13:18:32 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 472301 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=-19.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, 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 1DBB8C07E9B for ; Fri, 9 Jul 2021 13:18:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 070BC61377 for ; Fri, 9 Jul 2021 13:18:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231980AbhGINVk (ORCPT ); Fri, 9 Jul 2021 09:21:40 -0400 Received: from mail.kernel.org ([198.145.29.99]:51858 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231934AbhGINVh (ORCPT ); Fri, 9 Jul 2021 09:21:37 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 74ED5613B6; Fri, 9 Jul 2021 13:18:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1625836733; bh=2/6PFKcqQpIK27RimnGf9jRd+T7ijjCZEd7Fgyj2bVo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=nhFpbWdJUTz6/6Pmblr/mo+VrgQpt1AWgG80qHEXUChFZNDDiTgSMdigVJD8w3pQV QWBGOGOsXdx9WjLiugDOCqBHFOKRuS2jXgJZ3Y9exOSQJZGuBBFvicmBJBUpActupL 6zvN2rVBmawM6+mApLennwznXnGUbpccWym38O1U= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, ManYi Li , "Martin K. Petersen" , Sasha Levin Subject: [PATCH 4.9 5/9] scsi: sr: Return appropriate error code when disk is ejected Date: Fri, 9 Jul 2021 15:18:32 +0200 Message-Id: <20210709131550.250648459@linuxfoundation.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210709131542.410636747@linuxfoundation.org> References: <20210709131542.410636747@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: ManYi Li [ Upstream commit 7dd753ca59d6c8cc09aa1ed24f7657524803c7f3 ] Handle a reported media event code of 3. This indicates that the media has been removed from the drive and user intervention is required to proceed. Return DISK_EVENT_EJECT_REQUEST in that case. Link: https://lore.kernel.org/r/20210611094402.23884-1-limanyi@uniontech.com Signed-off-by: ManYi Li Signed-off-by: Martin K. Petersen Signed-off-by: Sasha Levin --- drivers/scsi/sr.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/scsi/sr.c b/drivers/scsi/sr.c index 67a73ea0a615..5e51a39a0c27 100644 --- a/drivers/scsi/sr.c +++ b/drivers/scsi/sr.c @@ -216,6 +216,8 @@ static unsigned int sr_get_events(struct scsi_device *sdev) return DISK_EVENT_EJECT_REQUEST; else if (med->media_event_code == 2) return DISK_EVENT_MEDIA_CHANGE; + else if (med->media_event_code == 3) + return DISK_EVENT_EJECT_REQUEST; return 0; } From patchwork Fri Jul 9 13:18:34 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 472300 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=-19.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, 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 F197AC11F67 for ; Fri, 9 Jul 2021 13:19:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DD1B4613C5 for ; Fri, 9 Jul 2021 13:19:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231976AbhGINVm (ORCPT ); Fri, 9 Jul 2021 09:21:42 -0400 Received: from mail.kernel.org ([198.145.29.99]:51918 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232021AbhGINVl (ORCPT ); Fri, 9 Jul 2021 09:21:41 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id E82AF61357; Fri, 9 Jul 2021 13:18:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1625836738; bh=aNIfBMAS+OUJJ23eapl/YTXCKRYtQWg8KfJDh4UNTkY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=HN8noom+uIbU1YHnuipGBIwnDRy9YTQTRecRZFP8FJcihOsSemuXXTYt9Sztn3MUN /kz7cuFVgzMG/XcVI23MRMz7f4/OSC2x1ykCf59b2oFYTQc2uEeNf3+a32oxUkW51R PVNgM0dUhP5DmPhAUc0nSEVKJ06e08LpojkiLDoM= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Petr Mladek , jenhaochen@google.com, Martin Liu , Minchan Kim , Nathan Chancellor , Nick Desaulniers , Oleg Nesterov , Tejun Heo , Andrew Morton , Linus Torvalds Subject: [PATCH 4.9 7/9] kthread_worker: split code for canceling the delayed work timer Date: Fri, 9 Jul 2021 15:18:34 +0200 Message-Id: <20210709131552.455038494@linuxfoundation.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210709131542.410636747@linuxfoundation.org> References: <20210709131542.410636747@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Petr Mladek commit 34b3d5344719d14fd2185b2d9459b3abcb8cf9d8 upstream. Patch series "kthread_worker: Fix race between kthread_mod_delayed_work() and kthread_cancel_delayed_work_sync()". This patchset fixes the race between kthread_mod_delayed_work() and kthread_cancel_delayed_work_sync() including proper return value handling. This patch (of 2): Simple code refactoring as a preparation step for fixing a race between kthread_mod_delayed_work() and kthread_cancel_delayed_work_sync(). It does not modify the existing behavior. Link: https://lkml.kernel.org/r/20210610133051.15337-2-pmladek@suse.com Signed-off-by: Petr Mladek Cc: Cc: Martin Liu Cc: Minchan Kim Cc: Nathan Chancellor Cc: Nick Desaulniers Cc: Oleg Nesterov Cc: Tejun Heo Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- kernel/kthread.c | 46 +++++++++++++++++++++++++++++----------------- 1 file changed, 29 insertions(+), 17 deletions(-) --- a/kernel/kthread.c +++ b/kernel/kthread.c @@ -952,6 +952,33 @@ void kthread_flush_work(struct kthread_w EXPORT_SYMBOL_GPL(kthread_flush_work); /* + * Make sure that the timer is neither set nor running and could + * not manipulate the work list_head any longer. + * + * The function is called under worker->lock. The lock is temporary + * released but the timer can't be set again in the meantime. + */ +static void kthread_cancel_delayed_work_timer(struct kthread_work *work, + unsigned long *flags) +{ + struct kthread_delayed_work *dwork = + container_of(work, struct kthread_delayed_work, work); + struct kthread_worker *worker = work->worker; + + /* + * del_timer_sync() must be called to make sure that the timer + * callback is not running. The lock must be temporary released + * to avoid a deadlock with the callback. In the meantime, + * any queuing is blocked by setting the canceling counter. + */ + work->canceling++; + spin_unlock_irqrestore(&worker->lock, *flags); + del_timer_sync(&dwork->timer); + spin_lock_irqsave(&worker->lock, *flags); + work->canceling--; +} + +/* * This function removes the work from the worker queue. Also it makes sure * that it won't get queued later via the delayed work's timer. * @@ -965,23 +992,8 @@ static bool __kthread_cancel_work(struct unsigned long *flags) { /* Try to cancel the timer if exists. */ - if (is_dwork) { - struct kthread_delayed_work *dwork = - container_of(work, struct kthread_delayed_work, work); - struct kthread_worker *worker = work->worker; - - /* - * del_timer_sync() must be called to make sure that the timer - * callback is not running. The lock must be temporary released - * to avoid a deadlock with the callback. In the meantime, - * any queuing is blocked by setting the canceling counter. - */ - work->canceling++; - spin_unlock_irqrestore(&worker->lock, *flags); - del_timer_sync(&dwork->timer); - spin_lock_irqsave(&worker->lock, *flags); - work->canceling--; - } + if (is_dwork) + kthread_cancel_delayed_work_timer(work, flags); /* * Try to remove the work from a worker list. It might either From patchwork Fri Jul 9 13:18:36 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 472299 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=-19.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, 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 85395C07E99 for ; Fri, 9 Jul 2021 13:19:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 72D43613C0 for ; Fri, 9 Jul 2021 13:19:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232033AbhGINVr (ORCPT ); Fri, 9 Jul 2021 09:21:47 -0400 Received: from mail.kernel.org ([198.145.29.99]:52056 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232012AbhGINVq (ORCPT ); Fri, 9 Jul 2021 09:21:46 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 7662261377; Fri, 9 Jul 2021 13:19:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1625836742; bh=CppCowU1aarDvakbgdnA1ps4raPDQHMaHM2QZfmD8Y4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=NI9vNVp9/RcrBmGNWZyWd3tza2bPpbdhHRBJyBgg2lC5IXQdgstYPfL9GQY5qv2/C edlEPIElCt7pccGeoRPIUV5OlAMhZER1wUO0zypuBSa6CijjiPL9l7qR/mK7yOXMWP alfCLqA8LKu0wsPG9afoHf8huOQ18l/6D76RmB8k= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Julien Grall , Juergen Gross , Boris Ostrovsky Subject: [PATCH 4.9 9/9] xen/events: reset active flag for lateeoi events later Date: Fri, 9 Jul 2021 15:18:36 +0200 Message-Id: <20210709131555.133915565@linuxfoundation.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210709131542.410636747@linuxfoundation.org> References: <20210709131542.410636747@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Juergen Gross commit 3de218ff39b9e3f0d453fe3154f12a174de44b25 upstream. In order to avoid a race condition for user events when changing cpu affinity reset the active flag only when EOI-ing the event. This is working fine as all user events are lateeoi events. Note that lateeoi_ack_mask_dynirq() is not modified as there is no explicit call to xen_irq_lateeoi() expected later. Cc: stable@vger.kernel.org Reported-by: Julien Grall Fixes: b6622798bc50b62 ("xen/events: avoid handling the same event on two cpus at the same time") Tested-by: Julien Grall Signed-off-by: Juergen Gross Reviewed-by: Boris Ostrovsky Link: https://lore.kernel.org/r/20210623130913.9405-1-jgross@suse.com Signed-off-by: Juergen Gross Signed-off-by: Greg Kroah-Hartman --- drivers/xen/events/events_base.c | 23 +++++++++++++++++++---- 1 file changed, 19 insertions(+), 4 deletions(-) --- a/drivers/xen/events/events_base.c +++ b/drivers/xen/events/events_base.c @@ -533,6 +533,9 @@ static void xen_irq_lateeoi_locked(struc } info->eoi_time = 0; + + /* is_active hasn't been reset yet, do it now. */ + smp_store_release(&info->is_active, 0); do_unmask(info, EVT_MASK_REASON_EOI_PENDING); } @@ -1778,10 +1781,22 @@ static void lateeoi_ack_dynirq(struct ir struct irq_info *info = info_for_irq(data->irq); evtchn_port_t evtchn = info ? info->evtchn : 0; - if (VALID_EVTCHN(evtchn)) { - do_mask(info, EVT_MASK_REASON_EOI_PENDING); - ack_dynirq(data); - } + if (!VALID_EVTCHN(evtchn)) + return; + + do_mask(info, EVT_MASK_REASON_EOI_PENDING); + + if (unlikely(irqd_is_setaffinity_pending(data)) && + likely(!irqd_irq_disabled(data))) { + do_mask(info, EVT_MASK_REASON_TEMPORARY); + + clear_evtchn(evtchn); + + irq_move_masked_irq(data); + + do_unmask(info, EVT_MASK_REASON_TEMPORARY); + } else + clear_evtchn(evtchn); } static void lateeoi_mask_ack_dynirq(struct irq_data *data)