Re: [PATCH v2 04/10] sysfb: Replace screen_info with sysfb_primary_display

Bjorn Helgaas
2025-11-24T23:56:42Z

On Mon, Nov 24, 2025 at 05:40:16PM +0100, Thomas Zimmermann wrote:
> Replace the global screen_info with sysfb_primary_display of type
> struct sysfb_display_info. Adapt all users of screen_info.
>
> Instances of screen_info are defined for x86, loongarch and EFI,
> with only one instance compiled into a specific build. Replace all
> of them with sysfb_primary_display.
>
> All existing users of screen_info are updated by pointing them to
> sysfb_primary_display.screen instead. This introduces some churn to
> the code, but has no impact on functionality.
>
> Boot parameters and EFI config tables are unchanged. They transfer
> screen_info as before. The logic in EFI's alloc_screen_info() changes
> slightly, as it now returns the screen field of sysfb_primary_display.
>
> v2:
> - update comment
> - rename init_screen_info() to init_primary_display()
>
> Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
> Acked-by: Arnd Bergmann <arnd@arndb.de>
> Acked-by: Ard Biesheuvel <ardb@kernel.org>

Acked-by: Bjorn Helgaas <bhelgaas@google.com> # drivers/pci/

> ---
> arch/arm64/kernel/image-vars.h | 2 +-
> arch/loongarch/kernel/efi.c | 15 +++++++------
> arch/loongarch/kernel/image-vars.h | 2 +-
> arch/riscv/kernel/image-vars.h | 2 +-
> arch/x86/kernel/kexec-bzimage64.c | 4 +++-
> arch/x86/kernel/setup.c | 10 +++++----
> arch/x86/video/video-common.c | 4 ++--
> drivers/firmware/efi/earlycon.c | 8 +++----
> drivers/firmware/efi/efi-init.c | 22 +++++++++----------
> drivers/firmware/efi/libstub/efi-stub-entry.c | 18 ++++++++++-----
> drivers/firmware/efi/sysfb_efi.c | 4 ++--
> drivers/firmware/sysfb.c | 6 ++---
> drivers/hv/vmbus_drv.c | 6 ++---
> drivers/pci/vgaarb.c | 4 ++--
> drivers/video/screen_info_pci.c | 5 +++--
> include/linux/screen_info.h | 2 --
> include/linux/sysfb.h | 5 +++--
> 17 files changed, 66 insertions(+), 53 deletions(-)
>
> diff --git a/arch/arm64/kernel/image-vars.h b/arch/arm64/kernel/image-vars.h
> index 85bc629270bd..d7b0d12b1015 100644
> --- a/arch/arm64/kernel/image-vars.h
> +++ b/arch/arm64/kernel/image-vars.h
> @@ -38,7 +38,7 @@ PROVIDE(__efistub__end = _end);
> PROVIDE(__efistub___inittext_end = __inittext_end);
> PROVIDE(__efistub__edata = _edata);
> #if defined(CONFIG_EFI_EARLYCON) || defined(CONFIG_SYSFB)
> -PROVIDE(__efistub_screen_info = screen_info);
> +PROVIDE(__efistub_sysfb_primary_display = sysfb_primary_display);
> #endif
> PROVIDE(__efistub__ctype = _ctype);
>
> diff --git a/arch/loongarch/kernel/efi.c b/arch/loongarch/kernel/efi.c
> index 860a3bc030e0..638a392d2cd2 100644
> --- a/arch/loongarch/kernel/efi.c
> +++ b/arch/loongarch/kernel/efi.c
> @@ -18,7 +18,7 @@
> #include <linux/kobject.h>
> #include <linux/memblock.h>
> #include <linux/reboot.h>
> -#include <linux/screen_info.h>
> +#include <linux/sysfb.h>
> #include <linux/uaccess.h>
>
> #include <asm/early_ioremap.h>
> @@ -75,11 +75,11 @@ bool efi_poweroff_required(void)
> unsigned long __initdata screen_info_table = EFI_INVALID_TABLE_ADDR;
>
> #if defined(CONFIG_SYSFB) || defined(CONFIG_EFI_EARLYCON)
> -struct screen_info screen_info __section(".data");
> -EXPORT_SYMBOL_GPL(screen_info);
> +struct sysfb_display_info sysfb_primary_display __section(".data");
> +EXPORT_SYMBOL_GPL(sysfb_primary_display);
> #endif
>
> -static void __init init_screen_info(void)
> +static void __init init_primary_display(void)
> {
> struct screen_info *si;
>
> @@ -91,11 +91,12 @@ static void __init init_screen_info(void)
> pr_err("Could not map screen_info config table\n");
> return;
> }
> - screen_info = *si;
> + sysfb_primary_display.screen = *si;
> memset(si, 0, sizeof(*si));
> early_memunmap(si, sizeof(*si));
>
> - memblock_reserve(__screen_info_lfb_base(&screen_info), screen_info.lfb_size);
> + memblock_reserve(__screen_info_lfb_base(&sysfb_primary_display.screen),
> + sysfb_primary_display.screen.lfb_size);
> }
>
> void __init efi_init(void)
> @@ -127,7 +128,7 @@ void __init efi_init(void)
> set_bit(EFI_CONFIG_TABLES, &efi.flags);
>
> if (IS_ENABLED(CONFIG_EFI_EARLYCON) || IS_ENABLED(CONFIG_SYSFB))
> - init_screen_info();
> + init_primary_display();
>
> if (boot_memmap == EFI_INVALID_TABLE_ADDR)
> return;
> diff --git a/arch/loongarch/kernel/image-vars.h b/arch/loongarch/kernel/image-vars.h
> index 41ddcf56d21c..e557ebd46c2b 100644
> --- a/arch/loongarch/kernel/image-vars.h
> +++ b/arch/loongarch/kernel/image-vars.h
> @@ -12,7 +12,7 @@ __efistub_kernel_entry = kernel_entry;
> __efistub_kernel_asize = kernel_asize;
> __efistub_kernel_fsize = kernel_fsize;
> #if defined(CONFIG_EFI_EARLYCON) || defined(CONFIG_SYSFB)
> -__efistub_screen_info = screen_info;
> +__efistub_sysfb_primary_display = sysfb_primary_display;
> #endif
>
> #endif
> diff --git a/arch/riscv/kernel/image-vars.h b/arch/riscv/kernel/image-vars.h
> index 3df30dd1c458..3bd9d06a8b8f 100644
> --- a/arch/riscv/kernel/image-vars.h
> +++ b/arch/riscv/kernel/image-vars.h
> @@ -29,7 +29,7 @@ __efistub__end = _end;
> __efistub__edata = _edata;
> __efistub___init_text_end = __init_text_end;
> #if defined(CONFIG_EFI_EARLYCON) || defined(CONFIG_SYSFB)
> -__efistub_screen_info = screen_info;
> +__efistub_sysfb_primary_display = sysfb_primary_display;
> #endif
>
> #endif
> diff --git a/arch/x86/kernel/kexec-bzimage64.c b/arch/x86/kernel/kexec-bzimage64.c
> index c3244ac680d1..7508d0ccc740 100644
> --- a/arch/x86/kernel/kexec-bzimage64.c
> +++ b/arch/x86/kernel/kexec-bzimage64.c
> @@ -20,6 +20,7 @@
> #include <linux/of_fdt.h>
> #include <linux/efi.h>
> #include <linux/random.h>
> +#include <linux/sysfb.h>
>
> #include <asm/bootparam.h>
> #include <asm/setup.h>
> @@ -303,7 +304,8 @@ setup_boot_parameters(struct kimage *image, struct boot_params *params,
> params->hdr.hardware_subarch = boot_params.hdr.hardware_subarch;
>
> /* Copying screen_info will do? */
> - memcpy(&params->screen_info, &screen_info, sizeof(struct screen_info));
> + memcpy(&params->screen_info, &sysfb_primary_display.screen,
> + sizeof(sysfb_primary_display.screen));
>
> /* Fill in memsize later */
> params->screen_info.ext_mem_k = 0;
> diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
> index 1b2edd07a3e1..675e4b9deb1f 100644
> --- a/arch/x86/kernel/setup.c
> +++ b/arch/x86/kernel/setup.c
> @@ -22,6 +22,7 @@
> #include <linux/random.h>
> #include <linux/root_dev.h>
> #include <linux/static_call.h>
> +#include <linux/sysfb.h>
> #include <linux/swiotlb.h>
> #include <linux/tboot.h>
> #include <linux/usb/xhci-dbgp.h>
> @@ -211,8 +212,9 @@ arch_initcall(init_x86_sysctl);
> /*
> * Setup options
> */
> -struct screen_info screen_info;
> -EXPORT_SYMBOL(screen_info);
> +
> +struct sysfb_display_info sysfb_primary_display;
> +EXPORT_SYMBOL(sysfb_primary_display);
> #if defined(CONFIG_FIRMWARE_EDID)
> struct edid_info edid_info;
> EXPORT_SYMBOL_GPL(edid_info);
> @@ -526,7 +528,7 @@ static void __init parse_setup_data(void)
> static void __init parse_boot_params(void)
> {
> ROOT_DEV = old_decode_dev(boot_params.hdr.root_dev);
> - screen_info = boot_params.screen_info;
> + sysfb_primary_display.screen = boot_params.screen_info;
> #if defined(CONFIG_FIRMWARE_EDID)
> edid_info = boot_params.edid_info;
> #endif
> @@ -1254,7 +1256,7 @@ void __init setup_arch(char **cmdline_p)
> #ifdef CONFIG_VT
> #if defined(CONFIG_VGA_CONSOLE)
> if (!efi_enabled(EFI_BOOT) || (efi_mem_type(0xa0000) != EFI_CONVENTIONAL_MEMORY))
> - vgacon_register_screen(&screen_info);
> + vgacon_register_screen(&sysfb_primary_display.screen);
> #endif
> #endif
> x86_init.oem.banner();
> diff --git a/arch/x86/video/video-common.c b/arch/x86/video/video-common.c
> index e0aeee99bc99..152789f00fcd 100644
> --- a/arch/x86/video/video-common.c
> +++ b/arch/x86/video/video-common.c
> @@ -9,7 +9,7 @@
>
> #include <linux/module.h>
> #include <linux/pci.h>
> -#include <linux/screen_info.h>
> +#include <linux/sysfb.h>
> #include <linux/vgaarb.h>
>
> #include <asm/video.h>
> @@ -29,7 +29,7 @@ EXPORT_SYMBOL(pgprot_framebuffer);
> bool video_is_primary_device(struct device *dev)
> {
> #ifdef CONFIG_SCREEN_INFO
> - struct screen_info *si = &screen_info;
> + struct screen_info *si = &sysfb_primary_display.screen;
> struct resource res[SCREEN_INFO_MAX_RESOURCES];
> ssize_t i, numres;
> #endif
> diff --git a/drivers/firmware/efi/earlycon.c b/drivers/firmware/efi/earlycon.c
> index 42e3a173dac1..3d060d59968c 100644
> --- a/drivers/firmware/efi/earlycon.c
> +++ b/drivers/firmware/efi/earlycon.c
> @@ -9,7 +9,7 @@
> #include <linux/io.h>
> #include <linux/kernel.h>
> #include <linux/serial_core.h>
> -#include <linux/screen_info.h>
> +#include <linux/sysfb.h>
> #include <linux/string.h>
>
> #include <asm/early_ioremap.h>
> @@ -32,7 +32,7 @@ static void *efi_fb;
> */
> static int __init efi_earlycon_remap_fb(void)
> {
> - const struct screen_info *si = &screen_info;
> + const struct screen_info *si = &sysfb_primary_display.screen;
>
> /* bail if there is no bootconsole or it was unregistered already */
> if (!earlycon_console || !console_is_registered(earlycon_console))
> @@ -147,7 +147,7 @@ static void efi_earlycon_write_char(u32 *dst, unsigned char c, unsigned int h,
> static void
> efi_earlycon_write(struct console *con, const char *str, unsigned int num)
> {
> - const struct screen_info *si = &screen_info;
> + const struct screen_info *si = &sysfb_primary_display.screen;
> u32 cur_efi_x = efi_x;
> unsigned int len;
> const char *s;
> @@ -227,7 +227,7 @@ void __init efi_earlycon_reprobe(void)
> static int __init efi_earlycon_setup(struct earlycon_device *device,
> const char *opt)
> {
> - const struct screen_info *si = &screen_info;
> + const struct screen_info *si = &sysfb_primary_display.screen;
> u16 xres, yres;
> u32 i;
>
> diff --git a/drivers/firmware/efi/efi-init.c b/drivers/firmware/efi/efi-init.c
> index a65c2d5b9e7b..d1d418a34407 100644
> --- a/drivers/firmware/efi/efi-init.c
> +++ b/drivers/firmware/efi/efi-init.c
> @@ -19,7 +19,7 @@
> #include <linux/of_address.h>
> #include <linux/of_fdt.h>
> #include <linux/platform_device.h>
> -#include <linux/screen_info.h>
> +#include <linux/sysfb.h>
>
> #include <asm/efi.h>
>
> @@ -57,15 +57,15 @@ static phys_addr_t __init efi_to_phys(unsigned long addr)
> extern __weak const efi_config_table_type_t efi_arch_tables[];
>
> /*
> - * x86 defines its own screen_info and uses it even without EFI,
> - * everything else can get it from here.
> + * x86 defines its own instance of sysfb_primary_display and uses
> + * it even without EFI, everything else can get them from here.
> */
> #if !defined(CONFIG_X86) && (defined(CONFIG_SYSFB) || defined(CONFIG_EFI_EARLYCON))
> -struct screen_info screen_info __section(".data");
> -EXPORT_SYMBOL_GPL(screen_info);
> +struct sysfb_display_info sysfb_primary_display __section(".data");
> +EXPORT_SYMBOL_GPL(sysfb_primary_display);
> #endif
>
> -static void __init init_screen_info(void)
> +static void __init init_primary_display(void)
> {
> struct screen_info *si;
>
> @@ -75,13 +75,13 @@ static void __init init_screen_info(void)
> pr_err("Could not map screen_info config table\n");
> return;
> }
> - screen_info = *si;
> + sysfb_primary_display.screen = *si;
> memset(si, 0, sizeof(*si));
> early_memunmap(si, sizeof(*si));
>
> - if (memblock_is_map_memory(screen_info.lfb_base))
> - memblock_mark_nomap(screen_info.lfb_base,
> - screen_info.lfb_size);
> + if (memblock_is_map_memory(sysfb_primary_display.screen.lfb_base))
> + memblock_mark_nomap(sysfb_primary_display.screen.lfb_base,
> + sysfb_primary_display.screen.lfb_size);
>
> if (IS_ENABLED(CONFIG_EFI_EARLYCON))
> efi_earlycon_reprobe();
> @@ -274,5 +274,5 @@ void __init efi_init(void)
> if (IS_ENABLED(CONFIG_X86) ||
> IS_ENABLED(CONFIG_SYSFB) ||
> IS_ENABLED(CONFIG_EFI_EARLYCON))
> - init_screen_info();
> + init_primary_display();
> }
> diff --git a/drivers/firmware/efi/libstub/efi-stub-entry.c b/drivers/firmware/efi/libstub/efi-stub-entry.c
> index a6c049835190..401ecbbdf331 100644
> --- a/drivers/firmware/efi/libstub/efi-stub-entry.c
> +++ b/drivers/firmware/efi/libstub/efi-stub-entry.c
> @@ -1,13 +1,18 @@
> // SPDX-License-Identifier: GPL-2.0-only
>
> #include <linux/efi.h>
> -#include <linux/screen_info.h>
> +#include <linux/sysfb.h>
>
> #include <asm/efi.h>
>
> #include "efistub.h"
>
> -static unsigned long screen_info_offset;
> +static unsigned long kernel_image_offset;
> +
> +static void *kernel_image_addr(void *addr)
> +{
> + return addr + kernel_image_offset;
> +}
>
> struct screen_info *alloc_screen_info(void)
> {
> @@ -16,8 +21,11 @@ struct screen_info *alloc_screen_info(void)
>
> if (IS_ENABLED(CONFIG_X86) ||
> IS_ENABLED(CONFIG_EFI_EARLYCON) ||
> - IS_ENABLED(CONFIG_SYSFB))
> - return (void *)&screen_info + screen_info_offset;
> + IS_ENABLED(CONFIG_SYSFB)) {
> + struct sysfb_display_info *dpy = kernel_image_addr(&sysfb_primary_display);
> +
> + return &dpy->screen;
> + }
>
> return NULL;
> }
> @@ -73,7 +81,7 @@ efi_status_t __efiapi efi_pe_entry(efi_handle_t handle,
> return status;
> }
>
> - screen_info_offset = image_addr - (unsigned long)image->image_base;
> + kernel_image_offset = image_addr - (unsigned long)image->image_base;
>
> status = efi_stub_common(handle, image, image_addr, cmdline_ptr);
>
> diff --git a/drivers/firmware/efi/sysfb_efi.c b/drivers/firmware/efi/sysfb_efi.c
> index 8e0f9d08397f..46ad95084b50 100644
> --- a/drivers/firmware/efi/sysfb_efi.c
> +++ b/drivers/firmware/efi/sysfb_efi.c
> @@ -176,7 +176,7 @@ static int __init efifb_set_system(struct screen_info *si, const struct dmi_syst
>
> static int __init efifb_set_system_callback(const struct dmi_system_id *id)
> {
> - return efifb_set_system(&screen_info, id);
> + return efifb_set_system(&sysfb_primary_display.screen, id);
> }
>
> #define EFIFB_DMI_SYSTEM_ID(vendor, name, enumid) \
> @@ -316,7 +316,7 @@ static struct device_node *find_pci_overlap_node(void)
> }
>
> for_each_of_pci_range(&parser, &range)
> - if (efifb_overlaps_pci_range(&screen_info, &range))
> + if (efifb_overlaps_pci_range(&sysfb_primary_display.screen, &range))
> return np;
> }
> return NULL;
> diff --git a/drivers/firmware/sysfb.c b/drivers/firmware/sysfb.c
> index 916b28538a29..1f671f9219b0 100644
> --- a/drivers/firmware/sysfb.c
> +++ b/drivers/firmware/sysfb.c
> @@ -66,7 +66,7 @@ static bool sysfb_unregister(void)
> */
> void sysfb_disable(struct device *dev)
> {
> - struct screen_info *si = &screen_info;
> + struct screen_info *si = &sysfb_primary_display.screen;
> struct device *parent;
>
> mutex_lock(&disable_lock);
> @@ -92,7 +92,7 @@ EXPORT_SYMBOL_GPL(sysfb_disable);
> */
> bool sysfb_handles_screen_info(void)
> {
> - const struct screen_info *si = &screen_info;
> + const struct screen_info *si = &sysfb_primary_display.screen;
>
> return !!screen_info_video_type(si);
> }
> @@ -141,7 +141,7 @@ static struct device *sysfb_parent_dev(const struct screen_info *si)
>
> static __init int sysfb_init(void)
> {
> - struct screen_info *si = &screen_info;
> + struct screen_info *si = &sysfb_primary_display.screen;
> struct device *parent;
> unsigned int type;
> struct simplefb_platform_data mode;
> diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c
> index a53af6fe81a6..9c937190be81 100644
> --- a/drivers/hv/vmbus_drv.c
> +++ b/drivers/hv/vmbus_drv.c
> @@ -29,7 +29,7 @@
> #include <linux/delay.h>
> #include <linux/panic_notifier.h>
> #include <linux/ptrace.h>
> -#include <linux/screen_info.h>
> +#include <linux/sysfb.h>
> #include <linux/efi.h>
> #include <linux/random.h>
> #include <linux/kernel.h>
> @@ -2340,8 +2340,8 @@ static void __maybe_unused vmbus_reserve_fb(void)
> if (efi_enabled(EFI_BOOT)) {
> /* Gen2 VM: get FB base from EFI framebuffer */
> if (IS_ENABLED(CONFIG_SYSFB)) {
> - start = screen_info.lfb_base;
> - size = max_t(__u32, screen_info.lfb_size, 0x800000);
> + start = sysfb_primary_display.screen.lfb_base;
> + size = max_t(__u32, sysfb_primary_display.screen.lfb_size, 0x800000);
> }
> } else {
> /* Gen1 VM: get FB base from PCI */
> diff --git a/drivers/pci/vgaarb.c b/drivers/pci/vgaarb.c
> index 436fa7f4c387..805be9ea4a34 100644
> --- a/drivers/pci/vgaarb.c
> +++ b/drivers/pci/vgaarb.c
> @@ -26,7 +26,7 @@
> #include <linux/poll.h>
> #include <linux/miscdevice.h>
> #include <linux/slab.h>
> -#include <linux/screen_info.h>
> +#include <linux/sysfb.h>
> #include <linux/vt.h>
> #include <linux/console.h>
> #include <linux/acpi.h>
> @@ -557,7 +557,7 @@ EXPORT_SYMBOL(vga_put);
> static bool vga_is_firmware_default(struct pci_dev *pdev)
> {
> #if defined CONFIG_X86
> - return pdev == screen_info_pci_dev(&screen_info);
> + return pdev == screen_info_pci_dev(&sysfb_primary_display.screen);
> #else
> return false;
> #endif
> diff --git a/drivers/video/screen_info_pci.c b/drivers/video/screen_info_pci.c
> index 66bfc1d0a6dc..8f34d8a74f09 100644
> --- a/drivers/video/screen_info_pci.c
> +++ b/drivers/video/screen_info_pci.c
> @@ -4,6 +4,7 @@
> #include <linux/printk.h>
> #include <linux/screen_info.h>
> #include <linux/string.h>
> +#include <linux/sysfb.h>
>
> static struct pci_dev *screen_info_lfb_pdev;
> static size_t screen_info_lfb_bar;
> @@ -26,7 +27,7 @@ static bool __screen_info_relocation_is_valid(const struct screen_info *si, stru
>
> void screen_info_apply_fixups(void)
> {
> - struct screen_info *si = &screen_info;
> + struct screen_info *si = &sysfb_primary_display.screen;
>
> if (screen_info_lfb_pdev) {
> struct resource *pr = &screen_info_lfb_pdev->resource[screen_info_lfb_bar];
> @@ -75,7 +76,7 @@ static void screen_info_fixup_lfb(struct pci_dev *pdev)
> .flags = IORESOURCE_MEM,
> };
> const struct resource *pr;
> - const struct screen_info *si = &screen_info;
> + const struct screen_info *si = &sysfb_primary_display.screen;
>
> if (screen_info_lfb_pdev)
> return; // already found
> diff --git a/include/linux/screen_info.h b/include/linux/screen_info.h
> index 1690706206e8..c022403c599a 100644
> --- a/include/linux/screen_info.h
> +++ b/include/linux/screen_info.h
> @@ -151,6 +151,4 @@ static inline struct pci_dev *screen_info_pci_dev(const struct screen_info *si)
> }
> #endif
>
> -extern struct screen_info screen_info;
> -
> #endif /* _SCREEN_INFO_H */
> diff --git a/include/linux/sysfb.h b/include/linux/sysfb.h
> index 8b37247528bf..e8bde392c690 100644
> --- a/include/linux/sysfb.h
> +++ b/include/linux/sysfb.h
> @@ -8,11 +8,10 @@
> */
>
> #include <linux/err.h>
> +#include <linux/platform_data/simplefb.h>
> #include <linux/screen_info.h>
> #include <linux/types.h>
>
> -#include <linux/platform_data/simplefb.h>
> -
> struct device;
> struct platform_device;
> struct screen_info;
> @@ -65,6 +64,8 @@ struct sysfb_display_info {
> struct screen_info screen;
> };
>
> +extern struct sysfb_display_info sysfb_primary_display;
> +
> #ifdef CONFIG_SYSFB
>
> void sysfb_disable(struct device *dev);
> --
> 2.51.1
>