From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C221030505A; Wed, 15 Oct 2025 08:43:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760517784; cv=none; b=Z/41CgV49bRxkAZHMOSu5OAnhmF8lNc+/4+86x0qqS/nSj1Gmj+4C6BObQWF9OBhg26owkOGIaZsaWFrGNMleEAGAYW/eogaEK72mgdv+zeiWgmeEZBD2VvLnsTUHNnEru8b0rO6/X3/QpSrhTZP1lz8r2p3/GI9gZ5Q2X5dArI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760517784; c=relaxed/simple; bh=t6yq5Uen6B5roB2c3mfJK71MirFBT5xt1IxrRWmQlXw=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=pEBBdg4NCnep4DUu4y5KL09N4bPUxB2i06AqI+yoccTbA5UngbL8br7A6j2ydqMTFOuWL6VVfw1nAIkrgbrW3C3b3RhYs2vkYXI2iZIFmOh1FSXBl7JTxb96XUCuemSnSyqv8IySRw5QUb+Y1wB6mn7wogP/2lZ3KMYSd3acGFE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=k5vfboGF; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="k5vfboGF" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 06368C4CEF8; Wed, 15 Oct 2025 08:43:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1760517784; bh=t6yq5Uen6B5roB2c3mfJK71MirFBT5xt1IxrRWmQlXw=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=k5vfboGF5t4jGo6mTRmlskU6x+hZ63WRJzj552AcYrufw/2fyVziIa2Xc++gmUK/h d35xoL+pcP34+1ER3olXZo1akV8qw9Qw60OyCLXf8FAm/oLAQsAqMOgureL7abvzSj Vo/qJe7JgGe3Mql0YTWz60wy5u4wcJv+UNgE570Q= Date: Wed, 15 Oct 2025 10:43:01 +0200 From: Greg Kroah-Hartman To: Wen Yang , Jon Hunter Cc: stable@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 6.1 0/6] fix invalid sleeping in detect_cache_attributes() Message-ID: <2025101509-bucktooth-reawake-5176@gregkh> References: Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Wed, Oct 01, 2025 at 01:27:25AM +0800, Wen Yang wrote: > commit 3fcbf1c77d08 ("arch_topology: Fix cache attributes detection > in the CPU hotplug path") > adds a call to detect_cache_attributes() to populate the cacheinfo > before updating the siblings mask. detect_cache_attributes() allocates > memory and can take the PPTT mutex (on ACPI platforms). On PREEMPT_RT > kernels, on secondary CPUs, this triggers a: > 'BUG: sleeping function called from invalid context' > as the code is executed with preemption and interrupts disabled: > > | BUG: sleeping function called from invalid context at kernel/locking/spinlock_rt.c:46 > | in_atomic(): 1, irqs_disabled(): 128, non_block: 0, pid: 0, name: swapper/111 > | preempt_count: 1, expected: 0 > | RCU nest depth: 1, expected: 1 > | 3 locks held by swapper/111/0: > | #0: (&pcp->lock){+.+.}-{3:3}, at: get_page_from_freelist+0x218/0x12c8 > | #1: (rcu_read_lock){....}-{1:3}, at: rt_spin_trylock+0x48/0xf0 > | #2: (&zone->lock){+.+.}-{3:3}, at: rmqueue_bulk+0x64/0xa80 > | irq event stamp: 0 > | hardirqs last enabled at (0): 0x0 > | hardirqs last disabled at (0): copy_process+0x5dc/0x1ab8 > | softirqs last enabled at (0): copy_process+0x5dc/0x1ab8 > | softirqs last disabled at (0): 0x0 > | Preemption disabled at: > | migrate_enable+0x30/0x130 > | CPU: 111 PID: 0 Comm: swapper/111 Tainted: G W 6.0.0-rc4-rt6-[...] > | Call trace: > | __kmalloc+0xbc/0x1e8 > | detect_cache_attributes+0x2d4/0x5f0 > | update_siblings_masks+0x30/0x368 > | store_cpu_topology+0x78/0xb8 > | secondary_start_kernel+0xd0/0x198 > | __secondary_switched+0xb0/0xb4 > > > Pierre fixed this issue in the upstream 6.3 and the original series is follows: > https://lore.kernel.org/all/167404285593.885445.6219705651301997538.b4-ty@arm.com/ > > We also encountered the same issue on 6.1 stable branch, and need to backport this series. > > Pierre Gondois (6): > cacheinfo: Use RISC-V's init_cache_level() as generic OF > implementation > cacheinfo: Return error code in init_of_cache_level() > cacheinfo: Check 'cache-unified' property to count cache leaves > ACPI: PPTT: Remove acpi_find_cache_levels() > ACPI: PPTT: Update acpi_find_last_cache_level() to > acpi_get_cache_info() > arch_topology: Build cacheinfo from primary CPU This series seems to have broken existing systems, as reported here: https://lore.kernel.org/r/046f08cb-0610-48c9-af24-4804367df177@nvidia.com so I'm going to drop it from the queue at this point in time. Please work to resolve this before resubmitting it. thanks, greg k-h