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 lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 5FD23C32771 for ; Fri, 19 Aug 2022 11:29:41 +0000 (UTC) Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4M8KKc0Psmz3dyS for ; Fri, 19 Aug 2022 21:29:40 +1000 (AEST) Received: from gandalf.ozlabs.org (gandalf.ozlabs.org [150.107.74.76]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4M8KKB6Qmzz3cFd for ; Fri, 19 Aug 2022 21:29:18 +1000 (AEST) 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 ECDHE (P-256) server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by mail.ozlabs.org (Postfix) with ESMTPSA id 4M8KKB5Ttpz4x1N; Fri, 19 Aug 2022 21:29:18 +1000 (AEST) From: Michael Ellerman To: Michael Ellerman , linuxppc-dev@lists.ozlabs.org In-Reply-To: <20220815065550.1303620-1-mpe@ellerman.id.au> References: <20220815065550.1303620-1-mpe@ellerman.id.au> Subject: Re: [PATCH] powerpc/pci: Fix get_phb_number() locking Message-Id: <166090854459.441873.16971335069896983225.b4-ty@ellerman.id.au> Date: Fri, 19 Aug 2022 21:29:04 +1000 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: pali@kernel.org, linux@roeck-us.net Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On Mon, 15 Aug 2022 16:55:50 +1000, Michael Ellerman wrote: > The recent change to get_phb_number() causes a DEBUG_ATOMIC_SLEEP > warning on some systems: > > BUG: sleeping function called from invalid context at kernel/locking/mutex.c:580 > in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 1, name: swapper > preempt_count: 1, expected: 0 > RCU nest depth: 0, expected: 0 > 1 lock held by swapper/1: > #0: c157efb0 (hose_spinlock){+.+.}-{2:2}, at: pcibios_alloc_controller+0x64/0x220 > Preemption disabled at: > [<00000000>] 0x0 > CPU: 0 PID: 1 Comm: swapper Not tainted 5.19.0-yocto-standard+ #1 > Call Trace: > [d101dc90] [c073b264] dump_stack_lvl+0x50/0x8c (unreliable) > [d101dcb0] [c0093b70] __might_resched+0x258/0x2a8 > [d101dcd0] [c0d3e634] __mutex_lock+0x6c/0x6ec > [d101dd50] [c0a84174] of_alias_get_id+0x50/0xf4 > [d101dd80] [c002ec78] pcibios_alloc_controller+0x1b8/0x220 > [d101ddd0] [c140c9dc] pmac_pci_init+0x198/0x784 > [d101de50] [c140852c] discover_phbs+0x30/0x4c > [d101de60] [c0007fd4] do_one_initcall+0x94/0x344 > [d101ded0] [c1403b40] kernel_init_freeable+0x1a8/0x22c > [d101df10] [c00086e0] kernel_init+0x34/0x160 > [d101df30] [c001b334] ret_from_kernel_thread+0x5c/0x64 > > [...] Applied to powerpc/fixes. [1/1] powerpc/pci: Fix get_phb_number() locking https://git.kernel.org/powerpc/c/8d48562a2729742f767b0fdd994d6b2a56a49c63 cheers