lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <CAKv+Gu-U3JxbhYPpmm9synQXeqe11gFwntGVBTHsmmiPenQNmw@mail.gmail.com>
Date:   Thu, 12 Jan 2017 16:20:41 +0000
From:   Ard Biesheuvel <ard.biesheuvel@...aro.org>
To:     Dave Young <dyoung@...hat.com>
Cc:     Matt Fleming <matt@...eblueprint.co.uk>,
        "linux-efi@...r.kernel.org" <linux-efi@...r.kernel.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        "x86@...nel.org" <x86@...nel.org>,
        Nicolai Stange <nicstange@...il.com>,
        Ingo Molnar <mingo@...nel.org>,
        Thomas Gleixner <tglx@...utronix.de>,
        "hpa@...or.com" <hpa@...or.com>,
        Dan Williams <dan.j.williams@...el.com>,
        Mika Penttilä <mika.penttila@...tfour.com>,
        bhsharma@...hat.com
Subject: Re: [PATCH 2/4] efi/x86: move efi bgrt init code to early init code

On 12 January 2017 at 09:41, Dave Young <dyoung@...hat.com> wrote:
> Before invoking the arch specific handler, efi_mem_reserve() reserves
> the given memory region through memblock.
>
> efi_bgrt_init will call efi_mem_reserve after mm_init(), at that time
> memblock is dead and it should not be used any more.
>
> efi bgrt code depend on acpi intialization to get the bgrt acpi table,
> moving bgrt parsing to acpi early boot code can make sure efi_mem_reserve
> in efi bgrt code still use memblock safely.
>
> Signed-off-by: Dave Young <dyoung@...hat.com>

I know this is probably out of scope for you, but since we're moving
things around, any chance we could do so in a manner that will enable
BGRT support for arm64/ACPI? Happy to test/collaborate on this.


> ---
>  arch/x86/kernel/acpi/boot.c      |   12 +++++++++++
>  arch/x86/platform/efi/efi-bgrt.c |   42 +++++++++++++--------------------------
>  arch/x86/platform/efi/efi.c      |    5 ----
>  drivers/acpi/bgrt.c              |   21 +++++++++++++------
>  include/linux/efi-bgrt.h         |    7 ++----
>  init/main.c                      |    1
>  6 files changed, 45 insertions(+), 43 deletions(-)
>
> --- linux-x86.orig/arch/x86/kernel/acpi/boot.c
> +++ linux-x86/arch/x86/kernel/acpi/boot.c
> @@ -35,6 +35,7 @@
>  #include <linux/bootmem.h>
>  #include <linux/ioport.h>
>  #include <linux/pci.h>
> +#include <linux/efi-bgrt.h>
>
>  #include <asm/irqdomain.h>
>  #include <asm/pci_x86.h>
> @@ -1557,6 +1558,14 @@ int __init early_acpi_boot_init(void)
>         return 0;
>  }
>
> +#ifdef CONFIG_ACPI_BGRT
> +static int __init acpi_parse_bgrt(struct acpi_table_header *table)
> +{
> +       efi_bgrt_init(table);
> +       return 0;
> +}
> +#endif
> +
>  int __init acpi_boot_init(void)
>  {
>         /* those are executed after early-quirks are executed */
> @@ -1581,6 +1590,9 @@ int __init acpi_boot_init(void)
>         acpi_process_madt();
>
>         acpi_table_parse(ACPI_SIG_HPET, acpi_parse_hpet);
> +#ifdef CONFIG_ACPI_BGRT
> +       acpi_table_parse("BGRT", acpi_parse_bgrt);
> +#endif
>
>         if (!acpi_noirq)
>                 x86_init.pci.init = pci_acpi_init;
> --- linux-x86.orig/arch/x86/platform/efi/efi-bgrt.c
> +++ linux-x86/arch/x86/platform/efi/efi-bgrt.c
> @@ -19,8 +19,7 @@
>  #include <linux/efi.h>
>  #include <linux/efi-bgrt.h>
>
> -struct acpi_table_bgrt *bgrt_tab;
> -void *__initdata bgrt_image;
> +struct acpi_table_bgrt bgrt_tab;
>  size_t __initdata bgrt_image_size;
>
>  struct bmp_header {
> @@ -28,53 +27,49 @@ struct bmp_header {
>         u32 size;
>  } __packed;
>
> -void __init efi_bgrt_init(void)
> +void __init efi_bgrt_init(struct acpi_table_header *table)
>  {
> -       acpi_status status;
>         void *image;
>         struct bmp_header bmp_header;
>
>         if (acpi_disabled)
>                 return;
>
> -       status = acpi_get_table("BGRT", 0,
> -                               (struct acpi_table_header **)&bgrt_tab);
> -       if (ACPI_FAILURE(status))
> -               return;
> +       bgrt_tab = *(struct acpi_table_bgrt *)table;
>
> -       if (bgrt_tab->header.length < sizeof(*bgrt_tab)) {
> +       if (bgrt_tab.header.length < sizeof(bgrt_tab)) {
>                 pr_notice("Ignoring BGRT: invalid length %u (expected %zu)\n",
> -                      bgrt_tab->header.length, sizeof(*bgrt_tab));
> +                      bgrt_tab.header.length, sizeof(bgrt_tab));
>                 return;
>         }
> -       if (bgrt_tab->version != 1) {
> +       if (bgrt_tab.version != 1) {
>                 pr_notice("Ignoring BGRT: invalid version %u (expected 1)\n",
> -                      bgrt_tab->version);
> +                      bgrt_tab.version);
>                 return;
>         }
> -       if (bgrt_tab->status & 0xfe) {
> +       if (bgrt_tab.status & 0xfe) {
>                 pr_notice("Ignoring BGRT: reserved status bits are non-zero %u\n",
> -                      bgrt_tab->status);
> +                      bgrt_tab.status);
>                 return;
>         }
> -       if (bgrt_tab->image_type != 0) {
> +       if (bgrt_tab.image_type != 0) {
>                 pr_notice("Ignoring BGRT: invalid image type %u (expected 0)\n",
> -                      bgrt_tab->image_type);
> +                      bgrt_tab.image_type);
>                 return;
>         }
> -       if (!bgrt_tab->image_address) {
> +       if (!bgrt_tab.image_address) {
>                 pr_notice("Ignoring BGRT: null image address\n");
>                 return;
>         }
>
> -       image = memremap(bgrt_tab->image_address, sizeof(bmp_header), MEMREMAP_WB);
> +       image = early_memremap(bgrt_tab.image_address, sizeof(bmp_header));
>         if (!image) {
>                 pr_notice("Ignoring BGRT: failed to map image header memory\n");
>                 return;
>         }
>
>         memcpy(&bmp_header, image, sizeof(bmp_header));
> -       memunmap(image);
> +       early_memunmap(image, sizeof(bmp_header));
>         if (bmp_header.id != 0x4d42) {
>                 pr_notice("Ignoring BGRT: Incorrect BMP magic number 0x%x (expected 0x4d42)\n",
>                         bmp_header.id);
> @@ -82,12 +77,5 @@ void __init efi_bgrt_init(void)
>         }
>         bgrt_image_size = bmp_header.size;
>
> -       bgrt_image = memremap(bgrt_tab->image_address, bmp_header.size, MEMREMAP_WB);
> -       if (!bgrt_image) {
> -               pr_notice("Ignoring BGRT: failed to map image memory\n");
> -               bgrt_image = NULL;
> -               return;
> -       }
> -
> -       efi_mem_reserve(bgrt_tab->image_address, bgrt_image_size);
> +       efi_mem_reserve(bgrt_tab.image_address, bgrt_image_size);
>  }
> --- linux-x86.orig/drivers/acpi/bgrt.c
> +++ linux-x86/drivers/acpi/bgrt.c
> @@ -15,40 +15,41 @@
>  #include <linux/sysfs.h>
>  #include <linux/efi-bgrt.h>
>
> +static void *bgrt_image;
>  static struct kobject *bgrt_kobj;
>
>  static ssize_t show_version(struct device *dev,
>                             struct device_attribute *attr, char *buf)
>  {
> -       return snprintf(buf, PAGE_SIZE, "%d\n", bgrt_tab->version);
> +       return snprintf(buf, PAGE_SIZE, "%d\n", bgrt_tab.version);
>  }
>  static DEVICE_ATTR(version, S_IRUGO, show_version, NULL);
>
>  static ssize_t show_status(struct device *dev,
>                            struct device_attribute *attr, char *buf)
>  {
> -       return snprintf(buf, PAGE_SIZE, "%d\n", bgrt_tab->status);
> +       return snprintf(buf, PAGE_SIZE, "%d\n", bgrt_tab.status);
>  }
>  static DEVICE_ATTR(status, S_IRUGO, show_status, NULL);
>
>  static ssize_t show_type(struct device *dev,
>                          struct device_attribute *attr, char *buf)
>  {
> -       return snprintf(buf, PAGE_SIZE, "%d\n", bgrt_tab->image_type);
> +       return snprintf(buf, PAGE_SIZE, "%d\n", bgrt_tab.image_type);
>  }
>  static DEVICE_ATTR(type, S_IRUGO, show_type, NULL);
>
>  static ssize_t show_xoffset(struct device *dev,
>                             struct device_attribute *attr, char *buf)
>  {
> -       return snprintf(buf, PAGE_SIZE, "%d\n", bgrt_tab->image_offset_x);
> +       return snprintf(buf, PAGE_SIZE, "%d\n", bgrt_tab.image_offset_x);
>  }
>  static DEVICE_ATTR(xoffset, S_IRUGO, show_xoffset, NULL);
>
>  static ssize_t show_yoffset(struct device *dev,
>                             struct device_attribute *attr, char *buf)
>  {
> -       return snprintf(buf, PAGE_SIZE, "%d\n", bgrt_tab->image_offset_y);
> +       return snprintf(buf, PAGE_SIZE, "%d\n", bgrt_tab.image_offset_y);
>  }
>  static DEVICE_ATTR(yoffset, S_IRUGO, show_yoffset, NULL);
>
> @@ -84,9 +85,17 @@ static int __init bgrt_init(void)
>  {
>         int ret;
>
> -       if (!bgrt_image)
> +       if (!bgrt_tab.image_address)
>                 return -ENODEV;
>
> +       bgrt_image = memremap(bgrt_tab.image_address, bgrt_image_size,
> +                             MEMREMAP_WB);
> +       if (!bgrt_image) {
> +               pr_notice("Ignoring BGRT: failed to map image memory\n");
> +               bgrt_image = NULL;
> +               return -ENOMEM;
> +       }
> +
>         bin_attr_image.private = bgrt_image;
>         bin_attr_image.size = bgrt_image_size;
>
> --- linux-x86.orig/include/linux/efi-bgrt.h
> +++ linux-x86/include/linux/efi-bgrt.h
> @@ -5,16 +5,15 @@
>
>  #include <linux/acpi.h>
>
> -void efi_bgrt_init(void);
> +void efi_bgrt_init(struct acpi_table_header *table);
>
>  /* The BGRT data itself; only valid if bgrt_image != NULL. */
> -extern void *bgrt_image;
>  extern size_t bgrt_image_size;
> -extern struct acpi_table_bgrt *bgrt_tab;
> +extern struct acpi_table_bgrt bgrt_tab;
>
>  #else /* !CONFIG_ACPI_BGRT */
>
> -static inline void efi_bgrt_init(void) {}
> +static inline void efi_bgrt_init(struct acpi_table_header *table) {}
>
>  #endif /* !CONFIG_ACPI_BGRT */
>
> --- linux-x86.orig/arch/x86/platform/efi/efi.c
> +++ linux-x86/arch/x86/platform/efi/efi.c
> @@ -476,11 +476,6 @@ void __init efi_init(void)
>                 efi_print_memmap();
>  }
>
> -void __init efi_late_init(void)
> -{
> -       efi_bgrt_init();
> -}
> -
>  void __init efi_set_executable(efi_memory_desc_t *md, bool executable)
>  {
>         u64 addr, npages;
> --- linux-x86.orig/init/main.c
> +++ linux-x86/init/main.c
> @@ -663,7 +663,6 @@ asmlinkage __visible void __init start_k
>         sfi_init_late();
>
>         if (efi_enabled(EFI_RUNTIME_SERVICES)) {
> -               efi_late_init();
>                 efi_free_boot_services();
>         }
>
>
>

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ