From patchwork Tue Oct 25 14:12:49 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Evgeniy Baskov X-Patchwork-Id: 13019340 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id EAB8EC04A95 for ; Tue, 25 Oct 2022 14:14:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233186AbiJYOOY (ORCPT ); Tue, 25 Oct 2022 10:14:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46334 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233088AbiJYONw (ORCPT ); Tue, 25 Oct 2022 10:13:52 -0400 Received: from mail.ispras.ru (mail.ispras.ru [83.149.199.84]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9BBFFA3F59; Tue, 25 Oct 2022 07:13:49 -0700 (PDT) Received: from localhost.localdomain (unknown [83.149.199.65]) by mail.ispras.ru (Postfix) with ESMTPSA id 1299040737A9; Tue, 25 Oct 2022 14:13:48 +0000 (UTC) DKIM-Filter: OpenDKIM Filter v2.11.0 mail.ispras.ru 1299040737A9 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ispras.ru; s=default; t=1666707228; bh=9Oa8gIXmKLPxydEwpaxKmSLJp4b7h3J3XaTRhGHbQeo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ZHia3ZZudhpA78loUcZzJz7uqaw7cROgur2+O23+5nL5KUiFRH013NdgkUEGnWYG/ VjtSfUkQzYH3PF8hb6h1ltuwFQGhjTAhxGcNdOgBC+QasyGc0c6mH6SQwvf+cheRhL sNQIxqFqA7mQpz7t95d6SmXYYSCuAIDKIOARGvug= From: Evgeniy Baskov To: Ard Biesheuvel Cc: Evgeniy Baskov , Borislav Petkov , Andy Lutomirski , Dave Hansen , Ingo Molnar , Peter Zijlstra , Thomas Gleixner , Alexey Khoroshilov , Peter Jones , lvc-project@linuxtesting.org, x86@kernel.org, linux-efi@vger.kernel.org, linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org Subject: [PATCH v2 11/23] x86/boot: Make console interface more abstract Date: Tue, 25 Oct 2022 17:12:49 +0300 Message-Id: <8052eb0bfd066a9d11c7f03f8eb03da0648bb643.1666705333.git.baskov@ispras.ru> X-Mailer: git-send-email 2.37.4 In-Reply-To: References: MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-hardening@vger.kernel.org To be able to extract kernel from EFI, console output functions need to be replaceable by alternative implementations. Make all of those functions pointers. Move serial console code to separate file. Signed-off-by: Evgeniy Baskov --- arch/x86/boot/compressed/Makefile | 2 +- arch/x86/boot/compressed/misc.c | 109 +------------------------ arch/x86/boot/compressed/misc.h | 9 ++- arch/x86/boot/compressed/putstr.c | 130 ++++++++++++++++++++++++++++++ 4 files changed, 139 insertions(+), 111 deletions(-) create mode 100644 arch/x86/boot/compressed/putstr.c diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile index 64de6c2b1740..f79273f46cc7 100644 --- a/arch/x86/boot/compressed/Makefile +++ b/arch/x86/boot/compressed/Makefile @@ -93,7 +93,7 @@ $(obj)/misc.o: $(obj)/../voffset.h vmlinux-objs-y := $(obj)/vmlinux.lds $(obj)/kernel_info.o $(obj)/head_$(BITS).o \ $(obj)/misc.o $(obj)/string.o $(obj)/cmdline.o $(obj)/error.o \ - $(obj)/piggy.o $(obj)/cpuflags.o + $(obj)/piggy.o $(obj)/cpuflags.o $(obj)/putstr.o vmlinux-objs-$(CONFIG_EARLY_PRINTK) += $(obj)/early_serial_console.o vmlinux-objs-$(CONFIG_RANDOMIZE_BASE) += $(obj)/kaslr.o diff --git a/arch/x86/boot/compressed/misc.c b/arch/x86/boot/compressed/misc.c index 0c7ec290044d..aa4a22bc9cf9 100644 --- a/arch/x86/boot/compressed/misc.c +++ b/arch/x86/boot/compressed/misc.c @@ -53,13 +53,6 @@ struct port_io_ops pio_ops; memptr free_mem_ptr; memptr free_mem_end_ptr; -static char *vidmem; -static int vidport; - -/* These might be accessed before .bss is cleared, so use .data instead. */ -static int lines __section(".data"); -static int cols __section(".data"); - #ifdef CONFIG_KERNEL_GZIP #include "../../../../lib/decompress_inflate.c" #endif @@ -92,95 +85,6 @@ static int cols __section(".data"); * ../header.S. */ -static void scroll(void) -{ - int i; - - memmove(vidmem, vidmem + cols * 2, (lines - 1) * cols * 2); - for (i = (lines - 1) * cols * 2; i < lines * cols * 2; i += 2) - vidmem[i] = ' '; -} - -#define XMTRDY 0x20 - -#define TXR 0 /* Transmit register (WRITE) */ -#define LSR 5 /* Line Status */ -static void serial_putchar(int ch) -{ - unsigned timeout = 0xffff; - - while ((inb(early_serial_base + LSR) & XMTRDY) == 0 && --timeout) - cpu_relax(); - - outb(ch, early_serial_base + TXR); -} - -void __putstr(const char *s) -{ - int x, y, pos; - char c; - - if (early_serial_base) { - const char *str = s; - while (*str) { - if (*str == '\n') - serial_putchar('\r'); - serial_putchar(*str++); - } - } - - if (lines == 0 || cols == 0) - return; - - x = boot_params->screen_info.orig_x; - y = boot_params->screen_info.orig_y; - - while ((c = *s++) != '\0') { - if (c == '\n') { - x = 0; - if (++y >= lines) { - scroll(); - y--; - } - } else { - vidmem[(x + cols * y) * 2] = c; - if (++x >= cols) { - x = 0; - if (++y >= lines) { - scroll(); - y--; - } - } - } - } - - boot_params->screen_info.orig_x = x; - boot_params->screen_info.orig_y = y; - - pos = (x + cols * y) * 2; /* Update cursor position */ - outb(14, vidport); - outb(0xff & (pos >> 9), vidport+1); - outb(15, vidport); - outb(0xff & (pos >> 1), vidport+1); -} - -void __puthex(unsigned long value) -{ - char alpha[2] = "0"; - int bits; - - for (bits = sizeof(value) * 8 - 4; bits >= 0; bits -= 4) { - unsigned long digit = (value >> bits) & 0xf; - - if (digit < 0xA) - alpha[0] = '0' + digit; - else - alpha[0] = 'a' + (digit - 0xA); - - __putstr(alpha); - } -} - #ifdef CONFIG_X86_NEED_RELOCS static void handle_relocations(void *output, unsigned long output_len, unsigned long virt_addr) @@ -406,17 +310,6 @@ asmlinkage __visible void *extract_kernel(void *rmode, memptr heap, sanitize_boot_params(boot_params); - if (boot_params->screen_info.orig_video_mode == 7) { - vidmem = (char *) 0xb0000; - vidport = 0x3b4; - } else { - vidmem = (char *) 0xb8000; - vidport = 0x3d4; - } - - lines = boot_params->screen_info.orig_video_lines; - cols = boot_params->screen_info.orig_video_cols; - init_default_io_ops(); /* @@ -427,7 +320,7 @@ asmlinkage __visible void *extract_kernel(void *rmode, memptr heap, */ early_tdx_detect(); - console_init(); + init_bare_console(); /* * Save RSDP address for later use. Have this after console_init() diff --git a/arch/x86/boot/compressed/misc.h b/arch/x86/boot/compressed/misc.h index 033db9b536e6..38d31bec062d 100644 --- a/arch/x86/boot/compressed/misc.h +++ b/arch/x86/boot/compressed/misc.h @@ -57,8 +57,8 @@ extern memptr free_mem_end_ptr; void *malloc(int size); void free(void *where); extern struct boot_params *boot_params; -void __putstr(const char *s); -void __puthex(unsigned long value); +extern void (*__putstr)(const char *s); +extern void (*__puthex)(unsigned long value); #define error_putstr(__x) __putstr(__x) #define error_puthex(__x) __puthex(__x) @@ -128,6 +128,11 @@ static inline void console_init(void) { } #endif +/* putstr.c */ +void init_bare_console(void); +void init_console_func(void (*putstr_)(const char *), + void (*puthex_)(unsigned long)); + #ifdef CONFIG_AMD_MEM_ENCRYPT void sev_enable(struct boot_params *bp); void sev_es_shutdown_ghcb(void); diff --git a/arch/x86/boot/compressed/putstr.c b/arch/x86/boot/compressed/putstr.c new file mode 100644 index 000000000000..44a4c3dacec5 --- /dev/null +++ b/arch/x86/boot/compressed/putstr.c @@ -0,0 +1,130 @@ +// SPDX-License-Identifier: GPL-2.0 +#include "misc.h" + +/* These might be accessed before .bss is cleared, so use .data instead. */ +static char *vidmem __section(".data"); +static int vidport __section(".data"); +static int lines __section(".data"); +static int cols __section(".data"); + +void (*__putstr)(const char *s); +void (*__puthex)(unsigned long value); + +static void putstr(const char *s); +static void puthex(unsigned long value); + +void init_console_func(void (*putstr_)(const char *), + void (*puthex_)(unsigned long)) +{ + __putstr = putstr_; + __puthex = puthex_; +} + +void init_bare_console(void) +{ + init_console_func(putstr, puthex); + + if (boot_params->screen_info.orig_video_mode == 7) { + vidmem = (char *) 0xb0000; + vidport = 0x3b4; + } else { + vidmem = (char *) 0xb8000; + vidport = 0x3d4; + } + + lines = boot_params->screen_info.orig_video_lines; + cols = boot_params->screen_info.orig_video_cols; + + console_init(); +} + +static void scroll(void) +{ + int i; + + memmove(vidmem, vidmem + cols * 2, (lines - 1) * cols * 2); + for (i = (lines - 1) * cols * 2; i < lines * cols * 2; i += 2) + vidmem[i] = ' '; +} + +#define XMTRDY 0x20 + +#define TXR 0 /* Transmit register (WRITE) */ +#define LSR 5 /* Line Status */ + +static void serial_putchar(int ch) +{ + unsigned int timeout = 0xffff; + + while ((inb(early_serial_base + LSR) & XMTRDY) == 0 && --timeout) + cpu_relax(); + + outb(ch, early_serial_base + TXR); +} + +static void putstr(const char *s) +{ + int x, y, pos; + char c; + + if (early_serial_base) { + const char *str = s; + + while (*str) { + if (*str == '\n') + serial_putchar('\r'); + serial_putchar(*str++); + } + } + + if (lines == 0 || cols == 0) + return; + + x = boot_params->screen_info.orig_x; + y = boot_params->screen_info.orig_y; + + while ((c = *s++) != '\0') { + if (c == '\n') { + x = 0; + if (++y >= lines) { + scroll(); + y--; + } + } else { + vidmem[(x + cols * y) * 2] = c; + if (++x >= cols) { + x = 0; + if (++y >= lines) { + scroll(); + y--; + } + } + } + } + + boot_params->screen_info.orig_x = x; + boot_params->screen_info.orig_y = y; + + pos = (x + cols * y) * 2; /* Update cursor position */ + outb(14, vidport); + outb(0xff & (pos >> 9), vidport+1); + outb(15, vidport); + outb(0xff & (pos >> 1), vidport+1); +} + +static void puthex(unsigned long value) +{ + char alpha[2] = "0"; + int bits; + + for (bits = sizeof(value) * 8 - 4; bits >= 0; bits -= 4) { + unsigned long digit = (value >> bits) & 0xf; + + if (digit < 0xA) + alpha[0] = '0' + digit; + else + alpha[0] = 'a' + (digit - 0xA); + + putstr(alpha); + } +}