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=-19.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 BFD9DC433E0 for ; Tue, 2 Feb 2021 20:07:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9057A64E4B for ; Tue, 2 Feb 2021 20:07:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240416AbhBBUHJ (ORCPT ); Tue, 2 Feb 2021 15:07:09 -0500 Received: from mail.kernel.org ([198.145.29.99]:36436 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232844AbhBBNnB (ORCPT ); Tue, 2 Feb 2021 08:43:01 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 3276264F66; Tue, 2 Feb 2021 13:40:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1612273205; bh=NP20O/wddR1JeAh//dmrlqiN0SyO+nUO9F4/uRim8es=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=QAGKCam/1F2iA+h43LHtJJCtCos70vZ2xiH57MXbuKvWO5TxROhQC/tnIfYtB+pyu 83QFVTLN4kAjuvYQTxlY3Dn837iZdLBXoptNHBc88KKBpKGMIl/+5Lu1xFU7bTkty4 bOsZEIu6q+iaQdGQ5ynUaG1THmCFEYpaDalUgFzc= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Juergen Gross , Andrew Cooper Subject: [PATCH 5.10 020/142] x86/xen: avoid warning in Xen pv guest with CONFIG_AMD_MEM_ENCRYPT enabled Date: Tue, 2 Feb 2021 14:36:23 +0100 Message-Id: <20210202132958.543511160@linuxfoundation.org> X-Mailer: git-send-email 2.30.0 In-Reply-To: <20210202132957.692094111@linuxfoundation.org> References: <20210202132957.692094111@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Juergen Gross commit 2e92493637a09547734f92c62a2471f6f0cb9a2c upstream. When booting a kernel which has been built with CONFIG_AMD_MEM_ENCRYPT enabled as a Xen pv guest a warning is issued for each processor: [ 5.964347] ------------[ cut here ]------------ [ 5.968314] WARNING: CPU: 0 PID: 1 at /home/gross/linux/head/arch/x86/xen/enlighten_pv.c:660 get_trap_addr+0x59/0x90 [ 5.972321] Modules linked in: [ 5.976313] CPU: 0 PID: 1 Comm: swapper/0 Tainted: G W 5.11.0-rc5-default #75 [ 5.980313] Hardware name: Dell Inc. OptiPlex 9020/0PC5F7, BIOS A05 12/05/2013 [ 5.984313] RIP: e030:get_trap_addr+0x59/0x90 [ 5.988313] Code: 42 10 83 f0 01 85 f6 74 04 84 c0 75 1d b8 01 00 00 00 c3 48 3d 00 80 83 82 72 08 48 3d 20 81 83 82 72 0c b8 01 00 00 00 eb db <0f> 0b 31 c0 c3 48 2d 00 80 83 82 48 ba 72 1c c7 71 1c c7 71 1c 48 [ 5.992313] RSP: e02b:ffffc90040033d38 EFLAGS: 00010202 [ 5.996313] RAX: 0000000000000001 RBX: ffffffff82a141d0 RCX: ffffffff8222ec38 [ 6.000312] RDX: ffffffff8222ec38 RSI: 0000000000000005 RDI: ffffc90040033d40 [ 6.004313] RBP: ffff8881003984a0 R08: 0000000000000007 R09: ffff888100398000 [ 6.008312] R10: 0000000000000007 R11: ffffc90040246000 R12: ffff8884082182a8 [ 6.012313] R13: 0000000000000100 R14: 000000000000001d R15: ffff8881003982d0 [ 6.016316] FS: 0000000000000000(0000) GS:ffff888408200000(0000) knlGS:0000000000000000 [ 6.020313] CS: e030 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 6.024313] CR2: ffffc900020ef000 CR3: 000000000220a000 CR4: 0000000000050660 [ 6.028314] Call Trace: [ 6.032313] cvt_gate_to_trap.part.7+0x3f/0x90 [ 6.036313] ? asm_exc_double_fault+0x30/0x30 [ 6.040313] xen_convert_trap_info+0x87/0xd0 [ 6.044313] xen_pv_cpu_up+0x17a/0x450 [ 6.048313] bringup_cpu+0x2b/0xc0 [ 6.052313] ? cpus_read_trylock+0x50/0x50 [ 6.056313] cpuhp_invoke_callback+0x80/0x4c0 [ 6.060313] _cpu_up+0xa7/0x140 [ 6.064313] cpu_up+0x98/0xd0 [ 6.068313] bringup_nonboot_cpus+0x4f/0x60 [ 6.072313] smp_init+0x26/0x79 [ 6.076313] kernel_init_freeable+0x103/0x258 [ 6.080313] ? rest_init+0xd0/0xd0 [ 6.084313] kernel_init+0xa/0x110 [ 6.088313] ret_from_fork+0x1f/0x30 [ 6.092313] ---[ end trace be9ecf17dceeb4f3 ]--- Reason is that there is no Xen pv trap entry for X86_TRAP_VC. Fix that by adding a generic trap handler for unknown traps and wire all unknown bare metal handlers to this generic handler, which will just crash the system in case such a trap will ever happen. Fixes: 0786138c78e793 ("x86/sev-es: Add a Runtime #VC Exception Handler") Cc: # v5.10 Signed-off-by: Juergen Gross Reviewed-by: Andrew Cooper Signed-off-by: Juergen Gross Signed-off-by: Greg Kroah-Hartman --- arch/x86/include/asm/idtentry.h | 1 + arch/x86/xen/enlighten_pv.c | 15 ++++++++++++++- arch/x86/xen/xen-asm.S | 1 + 3 files changed, 16 insertions(+), 1 deletion(-) --- a/arch/x86/include/asm/idtentry.h +++ b/arch/x86/include/asm/idtentry.h @@ -616,6 +616,7 @@ DECLARE_IDTENTRY_VC(X86_TRAP_VC, exc_vmm #ifdef CONFIG_XEN_PV DECLARE_IDTENTRY_XENCB(X86_TRAP_OTHER, exc_xen_hypervisor_callback); +DECLARE_IDTENTRY_RAW(X86_TRAP_OTHER, exc_xen_unknown_trap); #endif /* Device interrupts common/spurious */ --- a/arch/x86/xen/enlighten_pv.c +++ b/arch/x86/xen/enlighten_pv.c @@ -583,6 +583,13 @@ DEFINE_IDTENTRY_RAW(xenpv_exc_debug) exc_debug(regs); } +DEFINE_IDTENTRY_RAW(exc_xen_unknown_trap) +{ + /* This should never happen and there is no way to handle it. */ + pr_err("Unknown trap in Xen PV mode."); + BUG(); +} + struct trap_array_entry { void (*orig)(void); void (*xen)(void); @@ -631,6 +638,7 @@ static bool __ref get_trap_addr(void **a { unsigned int nr; bool ist_okay = false; + bool found = false; /* * Replace trap handler addresses by Xen specific ones. @@ -645,6 +653,7 @@ static bool __ref get_trap_addr(void **a if (*addr == entry->orig) { *addr = entry->xen; ist_okay = entry->ist_okay; + found = true; break; } } @@ -655,9 +664,13 @@ static bool __ref get_trap_addr(void **a nr = (*addr - (void *)early_idt_handler_array[0]) / EARLY_IDT_HANDLER_SIZE; *addr = (void *)xen_early_idt_handler_array[nr]; + found = true; } - if (WARN_ON(ist != 0 && !ist_okay)) + if (!found) + *addr = (void *)xen_asm_exc_xen_unknown_trap; + + if (WARN_ON(found && ist != 0 && !ist_okay)) return false; return true; --- a/arch/x86/xen/xen-asm.S +++ b/arch/x86/xen/xen-asm.S @@ -178,6 +178,7 @@ xen_pv_trap asm_exc_simd_coprocessor_err #ifdef CONFIG_IA32_EMULATION xen_pv_trap entry_INT80_compat #endif +xen_pv_trap asm_exc_xen_unknown_trap xen_pv_trap asm_exc_xen_hypervisor_callback __INIT