From patchwork Wed Jun 26 07:39:20 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zhiquan Li X-Patchwork-Id: 13712376 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.18]) (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 7CE951FBB; Wed, 26 Jun 2024 07:40:11 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.18 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719387613; cv=none; b=l8U0K+GFqjyHoaB/JYTNjmHs/D2pxdKTLalo8/gY6/hBVU3mwDJ9ryPeJDT1hDorKOw0BfNzlRgAayODHyVd0wJ4Mbld4Gaj4Ftif+okhOtTWc1pOVT7Uqo4kzsRHExrtWCbd8tucNSVXOA5OWHack/xStj2u7w9f94x2NYaW7Q= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719387613; c=relaxed/simple; bh=/mEnjOuNB484h5qzjDemSgISTr4DI31TAi1M46X2jyU=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=QnCgCrYpupJsMCqpCwhlizSgIdqryy51SVZUCaf9Uvg9dzHtFEtwDiaE472guiGeOo71rzRiPXSdbrvz6Ccpsh2VsC1OA6jziFiCnBZS5EbDHgIsLkphGa3DiZeA+7p+oxjH3tYVU8ijIx8uSsiAdjSbpLGtrFPjHsLLjQgjI2s= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com; spf=pass smtp.mailfrom=intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=bpCtWEqR; arc=none smtp.client-ip=192.198.163.18 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="bpCtWEqR" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1719387611; x=1750923611; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=/mEnjOuNB484h5qzjDemSgISTr4DI31TAi1M46X2jyU=; b=bpCtWEqRAANHX6dGst5WuNXKa1vymBOLYgDzQx63Bk6q0lJZ4+7HWWVP Rx8uZdOz8Jclci9mucaW1Uvvm1slav72w3dfIhMKMr44Vo6XzsGM64uK0 7ewfPgNgqQ/5f+4FQwcrIDjdHny4JH6pLqC1dbofEdm37HhZ/c9eftup5 B0CzBCow2vkh3gpmKo2MntIvKjZ8kwkh2VyPjCm94pqpx1h36WA+TSvls zXncyodBSWc0cY4fIs4L9lZa4xWDO5EdfALpuvrISZQbVJXouxo+9O9Qo aBiy9l3kWt9RBaONFwJli6jjGSnFiYNDNFCZ8s4rZ7xIk9doWQVskrCqK A==; X-CSE-ConnectionGUID: +Qt0hPT9Rzy3zBrYRSXzBw== X-CSE-MsgGUID: xOEweSvKRVCeP4CzhD20lQ== X-IronPort-AV: E=McAfee;i="6700,10204,11114"; a="16123697" X-IronPort-AV: E=Sophos;i="6.08,266,1712646000"; d="scan'208";a="16123697" Received: from fmviesa004.fm.intel.com ([10.60.135.144]) by fmvoesa112.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 26 Jun 2024 00:40:11 -0700 X-CSE-ConnectionGUID: /xPkeCTqRYOpD3q2awHX8w== X-CSE-MsgGUID: yVL0NG1xS7m/y5pLj2xNag== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.08,266,1712646000"; d="scan'208";a="48509823" Received: from unknown (HELO zhiquan-linux-dev.bj.intel.com) ([10.238.156.102]) by fmviesa004.fm.intel.com with ESMTP; 26 Jun 2024 00:40:08 -0700 From: Zhiquan Li To: tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, kirill.shutemov@linux.intel.com, x86@kernel.org Cc: rafael@kernel.org, hpa@zytor.com, linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org, zhiquan1.li@intel.com Subject: [PATCH] x86/acpi: fix panic while AP online later with kernel parameter maxcpus=1 Date: Wed, 26 Jun 2024 15:39:20 +0800 Message-Id: <20240626073920.176471-1-zhiquan1.li@intel.com> X-Mailer: git-send-email 2.25.1 Precedence: bulk X-Mailing-List: linux-acpi@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 The issue was found on the platform that using "Multiprocessor Wakeup Structure"[1] to startup secondary CPU, which is usually used by encrypted guest. When restrict boot time CPU to 1 with the kernel parameter "maxcpus=1" and bring other CPUs online later, there will be a kernel panic as below. The variable acpi_mp_wake_mailbox to hold the virtual address of MP Wakeup Structure mailbox will be set as readonly after initialization. If the first AP is brought online laster, the attemption to update it results in panic. Not like the physical address of MP Wakeup Structure mailbox, the readonly attribute is not necessary for its virtual address. [1] Details about the MP Wakeup structure can be found in ACPI v6.4, in the "Multiprocessor Wakeup Structure" section. BUG: unable to handle page fault for address: ffffffff83086978 #PF: supervisor write access in kernel mode #PF: error_code(0x0003) - permissions violation PGD 3832067 P4D 3833067 PUD 3834063 PMD 80000000030001a1 Oops: Oops: 0003 [#1] PREEMPT SMP NOPTI CPU: 0 PID: 175 Comm: systemd-udevd Not tainted 6.10.0-rc4+ #14 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS unknown 2/2/2022 RIP: 0010:acpi_wakeup_cpu+0xb2/0xe0 Call Trace: ? __die+0x20/0x70 ? page_fault_oops+0x80/0x140 ? exc_page_fault+0xdc/0x180 ? asm_exc_page_fault+0x22/0x30 ? _raw_read_unlock+0x18/0x40 ? acpi_wakeup_cpu+0xb2/0xe0 do_boot_cpu+0xeb/0x1f0 native_kick_ap+0xcb/0x150 ? __pfx_cpuhp_kick_ap_alive+0x10/0x10 cpuhp_invoke_callback+0x2d0/0x480 ? __pfx_trace_rb_cpu_prepare+0x10/0x10 __cpuhp_invoke_callback_range+0x78/0xe0 cpuhp_up_callbacks+0x28/0x100 _cpu_up+0xb9/0x120 cpu_up+0x91/0xe0 cpu_subsys_online+0x4d/0xe0 device_online+0x5f/0x80 online_store+0x8f/0xc0 kernfs_fop_write_iter+0x125/0x1c0 vfs_write+0x35c/0x480 ksys_write+0x5f/0xe0 do_syscall_64+0x63/0x170 entry_SYSCALL_64_after_hwframe+0x76/0x7e Signed-off-by: Zhiquan Li --- arch/x86/kernel/acpi/madt_wakeup.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) base-commit: 4fe5c16f5e5e0bd1a71a5ac79b5870f91b6b8e81 diff --git a/arch/x86/kernel/acpi/madt_wakeup.c b/arch/x86/kernel/acpi/madt_wakeup.c index 6cfe762be28b..d5ef6215583b 100644 --- a/arch/x86/kernel/acpi/madt_wakeup.c +++ b/arch/x86/kernel/acpi/madt_wakeup.c @@ -19,7 +19,7 @@ static u64 acpi_mp_wake_mailbox_paddr __ro_after_init; /* Virtual address of the Multiprocessor Wakeup Structure mailbox */ -static struct acpi_madt_multiproc_wakeup_mailbox *acpi_mp_wake_mailbox __ro_after_init; +static struct acpi_madt_multiproc_wakeup_mailbox *acpi_mp_wake_mailbox; static u64 acpi_mp_pgd __ro_after_init; static u64 acpi_mp_reset_vector_paddr __ro_after_init;