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=-15.8 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,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 D872FC11F65 for ; Tue, 29 Jun 2021 02:40:29 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 8C9E761D0C for ; Tue, 29 Jun 2021 02:40:29 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8C9E761D0C Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id E60908D00FE; Mon, 28 Jun 2021 22:40:28 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id E104E8D00F0; Mon, 28 Jun 2021 22:40:28 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id CD8A18D00FE; Mon, 28 Jun 2021 22:40:28 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0023.hostedemail.com [216.40.44.23]) by kanga.kvack.org (Postfix) with ESMTP id AB6508D00F0 for ; Mon, 28 Jun 2021 22:40:28 -0400 (EDT) Received: from smtpin35.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id A9347180A97C5 for ; Tue, 29 Jun 2021 02:40:28 +0000 (UTC) X-FDA: 78305207736.35.6E53568 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf01.hostedemail.com (Postfix) with ESMTP id 61DDE5001702 for ; Tue, 29 Jun 2021 02:40:28 +0000 (UTC) Received: by mail.kernel.org (Postfix) with ESMTPSA id 63D2761D12; Tue, 29 Jun 2021 02:40:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1624934427; bh=ennVxsdrnIN5AcDKUsHs7PKyicT0GbcfzLgIJJ7EsJU=; h=Date:From:To:Subject:In-Reply-To:From; b=bmsOdrKbb9ZpddlIWfRtb3ACsg0r1KcqqFGd21WIYXAJKyUSAe3If8yzvN3Yg7O1h r5eeJ/ADj6M29x4KffvFoT/tIS8VQ4zQ/AwfuQXH1GdEudUIoOQHHMrVaNCg/IwS8E 6UdL0TpH2dIYjW+w73VGLbB1GIGoQHplhtjaovK0= Date: Mon, 28 Jun 2021 19:40:27 -0700 From: Andrew Morton To: akpm@linux-foundation.org, aquini@redhat.com, atomlin@redhat.com, linux-mm@kvack.org, mhocko@suse.com, mm-commits@vger.kernel.org, npiggin@gmail.com, torvalds@linux-foundation.org, urezki@gmail.com Subject: [patch 137/192] mm: vmalloc: add cond_resched() in __vunmap() Message-ID: <20210629024027.tmU5aE_Lh%akpm@linux-foundation.org> In-Reply-To: <20210628193256.008961950a714730751c1423@linux-foundation.org> User-Agent: s-nail v14.8.16 Authentication-Results: imf01.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=bmsOdrKb; spf=pass (imf01.hostedemail.com: domain of akpm@linux-foundation.org designates 198.145.29.99 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org; dmarc=none X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: 61DDE5001702 X-Stat-Signature: uwdrby7xsznf76uhaxg96ao4ux5p764s X-HE-Tag: 1624934428-452239 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: From: Rafael Aquini Subject: mm: vmalloc: add cond_resched() in __vunmap() On non-preemptible kernel builds the watchdog can complain about soft lockups when vfree() is called against large vmalloc areas: [ 210.851798] kvmalloc-test: vmalloc(2199023255552) succeeded [ 238.654842] watchdog: BUG: soft lockup - CPU#181 stuck for 26s! [rmmod:5203] [ 238.662716] Modules linked in: kvmalloc_test(OE-) ... [ 238.772671] CPU: 181 PID: 5203 Comm: rmmod Tainted: G S OE 5.13.0-rc7+ #1 [ 238.781413] Hardware name: Intel Corporation PURLEY/PURLEY, BIOS PLYXCRB1.86B.0553.D01.1809190614 09/19/2018 [ 238.792383] RIP: 0010:free_unref_page+0x52/0x60 [ 238.797447] Code: 48 c1 fd 06 48 89 ee e8 9c d0 ff ff 84 c0 74 19 9c 41 5c fa 48 89 ee 48 89 df e8 b9 ea ff ff 41 f7 c4 00 02 00 00 74 01 fb 5b <5d> 41 5c c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 f0 29 77 [ 238.818406] RSP: 0018:ffffb4d87868fe98 EFLAGS: 00000206 [ 238.824236] RAX: 0000000000000000 RBX: 000000001da0c945 RCX: ffffb4d87868fe40 [ 238.832200] RDX: ffffd79d3beed108 RSI: ffffd7998501dc08 RDI: ffff9c6fbffd7010 [ 238.840166] RBP: 000000000d518cbd R08: ffffd7998501dc08 R09: 0000000000000001 [ 238.848131] R10: 0000000000000000 R11: ffffd79d3beee088 R12: 0000000000000202 [ 238.856095] R13: ffff9e5be3eceec0 R14: 0000000000000000 R15: 0000000000000000 [ 238.864059] FS: 00007fe082c2d740(0000) GS:ffff9f4c69b40000(0000) knlGS:0000000000000000 [ 238.873089] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 238.879503] CR2: 000055a000611128 CR3: 000000f6094f6006 CR4: 00000000007706e0 [ 238.887467] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 238.895433] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 238.903397] PKRU: 55555554 [ 238.906417] Call Trace: [ 238.909149] __vunmap+0x17c/0x220 [ 238.912851] __x64_sys_delete_module+0x13a/0x250 [ 238.918008] ? syscall_trace_enter.isra.20+0x13c/0x1b0 [ 238.923746] do_syscall_64+0x39/0x80 [ 238.927740] entry_SYSCALL_64_after_hwframe+0x44/0xae Like in other range zapping routines that iterate over a large list, lets just add cond_resched() within __vunmap()'s page-releasing loop in order to avoid the watchdog splats. Link: https://lkml.kernel.org/r/20210622225030.478384-1-aquini@redhat.com Signed-off-by: Rafael Aquini Acked-by: Nicholas Piggin Reviewed-by: Uladzislau Rezki (Sony) Reviewed-by: Aaron Tomlin Acked-by: Michal Hocko Signed-off-by: Andrew Morton --- mm/vmalloc.c | 1 + 1 file changed, 1 insertion(+) --- a/mm/vmalloc.c~mm-vmalloc-add-cond_resched-in-__vunmap +++ a/mm/vmalloc.c @@ -2567,6 +2567,7 @@ static void __vunmap(const void *addr, i BUG_ON(!page); __free_pages(page, page_order); + cond_resched(); } atomic_long_sub(area->nr_pages, &nr_vmalloc_pages); _