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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 72409C83F10 for ; Thu, 31 Aug 2023 05:37:12 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 7B3EC8E000A; Thu, 31 Aug 2023 01:37:11 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 764138D0001; Thu, 31 Aug 2023 01:37:11 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 652618E000A; Thu, 31 Aug 2023 01:37:11 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0013.hostedemail.com [216.40.44.13]) by kanga.kvack.org (Postfix) with ESMTP id 5569A8D0001 for ; Thu, 31 Aug 2023 01:37:11 -0400 (EDT) Received: from smtpin06.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay05.hostedemail.com (Postfix) with ESMTP id 1AE9D40130 for ; Thu, 31 Aug 2023 05:37:11 +0000 (UTC) X-FDA: 81183291462.06.9E9A47E Received: from gandalf.ozlabs.org (gandalf.ozlabs.org [150.107.74.76]) by imf08.hostedemail.com (Postfix) with ESMTP id A072016000A for ; Thu, 31 Aug 2023 05:37:08 +0000 (UTC) Authentication-Results: imf08.hostedemail.com; dkim=pass header.d=ellerman.id.au header.s=201909 header.b=KHPrudNz; dmarc=none; spf=pass (imf08.hostedemail.com: domain of mpe@ellerman.id.au designates 150.107.74.76 as permitted sender) smtp.mailfrom=mpe@ellerman.id.au ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1693460229; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=mcJI19k1bYWrsUV5RrSLseHCYsvRJp714W7vtEfnAuM=; b=3y5HlHU2V5Ew4c3bAfHa+Y/xQac+yNi3k5lHYoDz5po8yfru+GyaO0rS41MTWSrfKevJeI VhiZMiJOInDQVrRKBQ+L10Vh2gGrlIcueJ/imjV0fHc1yxSvG29S5balPw5p8z+sI+gDvI BlC+T88aPKpPu17HnTvdpEgqPeb57LA= ARC-Authentication-Results: i=1; imf08.hostedemail.com; dkim=pass header.d=ellerman.id.au header.s=201909 header.b=KHPrudNz; dmarc=none; spf=pass (imf08.hostedemail.com: domain of mpe@ellerman.id.au designates 150.107.74.76 as permitted sender) smtp.mailfrom=mpe@ellerman.id.au ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1693460229; a=rsa-sha256; cv=none; b=w64bll4CmcpMQo4y2iRnTbuGZ85iOGV4N3yIxBZRLEdqbMNcs4/p4vCdGPUPg90CMkF4Un u7/WcXmo+I/5uBnDunnDKAYgKGRRK8gVLmWsZvbuoqNrZW/MthLKEmo16B/Db2f9KLuCMh ZjSWZ9gE1Oy1KUxVk1qm0wPE/t77ULM= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ellerman.id.au; s=201909; t=1693460224; bh=mcJI19k1bYWrsUV5RrSLseHCYsvRJp714W7vtEfnAuM=; h=From:To:Cc:Subject:In-Reply-To:References:Date:From; b=KHPrudNz58s2FxY40QbiANhLtETTg3IVisYvwKTSN3A26Y7DWbl7e4lQXj9sr3w+S 7r9x5m0OqvSIZJasmu4WwN1APOTQQUDfNXAS/8ut0mhRQk8X3dFyMuWQBUEICNyZhA 2xFpt1sliwhFxJUz5n9BWh9VmOG2qaaAjzqmOWPAz8S+ISKGzSnJsygTu+KqNCdR9K W5COGeoRbzYAhMFM3iDi2s4bsnkzchbtmkAu0AK7m/fkYxTycrJ7A5iJ5QQUy7CJMv UYT9pqgcvX2x2jYCA/h2j5VFzlDteL3enwyq6MzBHrgcke4o2q5kusK1UtTHxW6uGk ikdmejXy4VZgw== Received: from authenticated.ozlabs.org (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by mail.ozlabs.org (Postfix) with ESMTPSA id 4Rbqfl3jrDz4wy0; Thu, 31 Aug 2023 15:37:03 +1000 (AEST) From: Michael Ellerman To: Andreas Schwab , "Liam R. Howlett" Cc: Andrew Morton , maple-tree@lists.infradead.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, stable@vger.kernel.org, linuxppc-dev@lists.ozlabs.org Subject: Re: [PATCH v2 1/2] maple_tree: Disable mas_wr_append() when other readers are possible In-Reply-To: <87bkeotin8.fsf@igel.home> References: <20230819004356.1454718-1-Liam.Howlett@oracle.com> <20230819004356.1454718-2-Liam.Howlett@oracle.com> <87bkeotin8.fsf@igel.home> Date: Thu, 31 Aug 2023 15:37:02 +1000 Message-ID: <87y1hr22o1.fsf@mail.lhotse> MIME-Version: 1.0 Content-Type: text/plain X-Rspam-User: X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: A072016000A X-Stat-Signature: ibg3wan44c8nq3x7jfu7oxkyd6dya1j8 X-HE-Tag: 1693460228-379747 X-HE-Meta: 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 AOKd4HAM PME6N86JDYjUARoVsMNuKR7LU/STabDmyrfk3is52lk5/vZdd5+zbviL7MUdZRHLEFTFbgFft/z68sqsCFKRGwE8idvzHa8c11zdyjpN5waF5ywY5b5nv213qwrz/K3sCnZF2hnNdahCPGAHL4ARL3g9kbl7d9tJu7d6r0YTxoNXJtbBwz3EU4FlIE6WBEp36Tuqe 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: Andreas Schwab writes: > This breaks booting on ppc32: Does enabling CONFIG_DEBUG_ATOMIC_SLEEP fix the crash? It did for me on qemu. cheers > Kernel attemptd to writ user page (1ff0) - exploit attempt? (uid: 0) > BUG: Unable to handle kernel data access on write at 0x00001ff0 > Faulting instruction address: 0xc0009554 > Vector: 300 (Data Access) at [c0b09d10] > pc: c0009554: do_softirq_own_stack+0x18/0x30 > lr: c004f480: __irq_exit_rcu+0x70/0xc0 > sp: c0b09dd0 > msr: 1032 > dar: 1ff0 > dsisr: 42000000 > current = 0xc0a08360 > pid = 0, comm = swapper > Linux version 6.5.0 ... > enter ? for help > [c0b09de0] c00ff480 __irq_exit_rcu+0x70/0xc0 > [c0b09df0] c0005a98 Decrementer_virt+0x108/0x10c > --- Exception: 900 (Decrementer) at c06cfa0c __schedule+0x4fc/0x510 > [c0b09ec0] c06cf75c __schedule+0x1cc/0x510 (unreliable) > [c0b09ef0] c06cfc90 __cond_resched+0x2c/0x54 > [c0b09f00] c06d07f8 mutex_lock_killable+0x18/0x5c > [c0b09f10] c013c404 pcpu_alloc+0x110/0x4dc > [c0b09f70] c000cc34 alloc_descr.isra.18+0x48/0x144 > [c0b09f90] c0988aa0 early_irq_init+0x64/0x8c > [c0b09fa0] c097a5a4 start_kernel+0x5b4/0x7b0 > [c0b09ff0] 00003dc0 > mon> > > -- > Andreas Schwab, schwab@linux-m68k.org > GPG Key fingerprint = 7578 EB47 D4E5 4D69 2510 2552 DF73 E780 A9DA AEC1 > "And now for something completely different."