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=-8.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=ham 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 54600ECE58C for ; Mon, 7 Oct 2019 15:22:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 22DC42053B for ; Mon, 7 Oct 2019 15:22:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728137AbfJGPWM (ORCPT ); Mon, 7 Oct 2019 11:22:12 -0400 Received: from gecko.sbs.de ([194.138.37.40]:47925 "EHLO gecko.sbs.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726334AbfJGPWL (ORCPT ); Mon, 7 Oct 2019 11:22:11 -0400 Received: from mail1.sbs.de (mail1.sbs.de [192.129.41.35]) by gecko.sbs.de (8.15.2/8.15.2) with ESMTPS id x97FLk7N003194 (version=TLSv1.2 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 7 Oct 2019 17:21:46 +0200 Received: from [139.23.77.210] ([139.23.77.210]) by mail1.sbs.de (8.15.2/8.15.2) with ESMTP id x97FKInq030040; Mon, 7 Oct 2019 17:20:18 +0200 Subject: Re: [PATCH v5 2/2] x86/jailhouse: Only enable platform UARTs if available To: Ralf Ramsauer , Borislav Petkov , x86@kernel.org, jailhouse-dev@googlegroups.com, linux-kernel@vger.kernel.org Cc: Ingo Molnar , "H . Peter Anvin" References: <20191007123819.161432-1-ralf.ramsauer@oth-regensburg.de> <20191007123819.161432-3-ralf.ramsauer@oth-regensburg.de> From: Jan Kiszka Message-ID: <26021872-8be0-566f-870e-bddbaf2b0dd4@siemens.com> Date: Mon, 7 Oct 2019 17:20:18 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.1.1 MIME-Version: 1.0 In-Reply-To: <20191007123819.161432-3-ralf.ramsauer@oth-regensburg.de> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 07.10.19 14:38, Ralf Ramsauer wrote: > ACPI tables aren't available if Linux runs as guest of the hypervisor > Jailhouse. This makes the 8250 driver probe for all platform UARTs as > it assumes that all platform are present in case of !ACPI. Jailhouse > will stop execution of Linux guest due to port access violation. > > So far, these access violations could be solved by tuning the > 8250.nr_uarts parameter but it has limitations: We can, e.g., only map > consecutive platform UARTs to Linux, and only in the sequence 0x3f8, > 0x2f8, 0x3e8, 0x2e8. > > Beginning from setup_data version 2, Jailhouse will place information of > available platform UARTs in setup_data. This allows for selective > activation of platform UARTs. > > This patch queries the setup_data version and activates only available > UARTS. It comes with backward compatibility, and will still support > older setup_data versions. In this case, Linux falls back to the old > behaviour. > > Signed-off-by: Ralf Ramsauer > --- > arch/x86/include/uapi/asm/bootparam.h | 3 + > arch/x86/kernel/jailhouse.c | 83 +++++++++++++++++++++++---- > 2 files changed, 74 insertions(+), 12 deletions(-) > > diff --git a/arch/x86/include/uapi/asm/bootparam.h b/arch/x86/include/uapi/asm/bootparam.h > index 43be437c9c71..db1e24e56e94 100644 > --- a/arch/x86/include/uapi/asm/bootparam.h > +++ b/arch/x86/include/uapi/asm/bootparam.h > @@ -152,6 +152,9 @@ struct jailhouse_setup_data { > __u8 standard_ioapic; > __u8 cpu_ids[255]; > } __attribute__((packed)) v1; > + struct { > + __u32 flags; > + } __attribute__((packed)) v2; > } __attribute__((packed)); > > /* The so-called "zeropage" */ > diff --git a/arch/x86/kernel/jailhouse.c b/arch/x86/kernel/jailhouse.c > index b9647add0063..95550c08ab23 100644 > --- a/arch/x86/kernel/jailhouse.c > +++ b/arch/x86/kernel/jailhouse.c > @@ -11,6 +11,7 @@ > #include > #include > #include > +#include > #include > #include > #include > @@ -23,9 +24,22 @@ > > static __initdata struct jailhouse_setup_data setup_data; > #define SETUP_DATA_V1_LEN (sizeof(setup_data.hdr) + sizeof(setup_data.v1)) > +#define SETUP_DATA_V2_LEN (SETUP_DATA_V1_LEN + sizeof(setup_data.v2)) > > static unsigned int precalibrated_tsc_khz; > > +static void jailhouse_setup_irq(unsigned int irq) > +{ > + struct mpc_intsrc mp_irq = { > + .type = MP_INTSRC, > + .irqtype = mp_INT, > + .irqflag = MP_IRQPOL_ACTIVE_HIGH | MP_IRQTRIG_EDGE, > + .srcbusirq = irq, > + .dstirq = irq, > + }; > + mp_save_irq(&mp_irq); > +} > + > static uint32_t jailhouse_cpuid_base(void) > { > if (boot_cpu_data.cpuid_level < 0 || > @@ -79,11 +93,6 @@ static void __init jailhouse_get_smp_config(unsigned int early) > .type = IOAPIC_DOMAIN_STRICT, > .ops = &mp_ioapic_irqdomain_ops, > }; > - struct mpc_intsrc mp_irq = { > - .type = MP_INTSRC, > - .irqtype = mp_INT, > - .irqflag = MP_IRQPOL_ACTIVE_HIGH | MP_IRQTRIG_EDGE, > - }; > unsigned int cpu; > > jailhouse_x2apic_init(); > @@ -100,12 +109,12 @@ static void __init jailhouse_get_smp_config(unsigned int early) > if (setup_data.v1.standard_ioapic) { > mp_register_ioapic(0, 0xfec00000, gsi_top, &ioapic_cfg); > > - /* Register 1:1 mapping for legacy UART IRQs 3 and 4 */ > - mp_irq.srcbusirq = mp_irq.dstirq = 3; > - mp_save_irq(&mp_irq); > - > - mp_irq.srcbusirq = mp_irq.dstirq = 4; > - mp_save_irq(&mp_irq); > + if (IS_ENABLED(CONFIG_SERIAL_8250) && > + setup_data.hdr.version < 2) { > + /* Register 1:1 mapping for legacy UART IRQs 3 and 4 */ > + jailhouse_setup_irq(3); > + jailhouse_setup_irq(4); > + } > } > } > > @@ -138,6 +147,53 @@ static int __init jailhouse_pci_arch_init(void) > return 0; > } > > +#ifdef CONFIG_SERIAL_8250 > +static bool jailhouse_uart_enabled(unsigned int uart_nr) > +{ > + return setup_data.v2.flags & BIT(uart_nr); > +} > + > +static void jailhouse_serial_fixup(int port, struct uart_port *up, > + u32 *capabilities) > +{ > + static const u16 pcuart_base[] = {0x3f8, 0x2f8, 0x3e8, 0x2e8}; > + unsigned int n; > + > + for (n = 0; n < ARRAY_SIZE(pcuart_base); n++) { > + if (pcuart_base[n] != up->iobase) > + continue; > + > + if (jailhouse_uart_enabled(n)) { > + pr_info("Enabling UART%u (port 0x%lx)\n", n, > + up->iobase); > + jailhouse_setup_irq(up->irq); > + } else { > + /* Deactivate UART if access isn't allowed */ > + up->iobase = 0; > + } > + break; > + } > +} > + > +static void jailhouse_serial_workaround(void) > +{ > + /* > + * There are flags inside setup_data that indicate availability of > + * platform UARTs since setup data version 2. > + * > + * In case of version 1, we don't know which UARTs belong Linux. In > + * this case, unconditionally register 1:1 mapping for legacy UART IRQs > + * 3 and 4. > + */ > + if (setup_data.hdr.version > 1) > + serial8250_set_isa_configurator(jailhouse_serial_fixup); > +} > +#else /* !CONFIG_SERIAL_8250 */ > +static inline void jailhouse_serial_workaround(void) > +{ > +} > +#endif /* CONFIG_SERIAL_8250 */ > + > static void __init jailhouse_init_platform(void) > { > u64 pa_data = boot_params.hdr.setup_data; > @@ -188,7 +244,8 @@ static void __init jailhouse_init_platform(void) > if (setup_data.hdr.version == 0 || > setup_data.hdr.compatible_version != > JAILHOUSE_SETUP_REQUIRED_VERSION || > - (setup_data.hdr.version >= 1 && header.len < SETUP_DATA_V1_LEN)) > + (setup_data.hdr.version == 1 && header.len < SETUP_DATA_V1_LEN) || > + (setup_data.hdr.version >= 2 && header.len < SETUP_DATA_V2_LEN)) > goto unsupported; > > pmtmr_ioport = setup_data.v1.pm_timer_address; > @@ -204,6 +261,8 @@ static void __init jailhouse_init_platform(void) > * are none in a non-root cell. > */ > disable_acpi(); > + > + jailhouse_serial_workaround(); > return; > > unsupported: > This was missing yet: Reviewed-by: Jan Kiszka Thanks, Jan -- Siemens AG, Corporate Technology, CT RDA IOT SES-DE Corporate Competence Center Embedded Linux