From 8b3a149db461d3286d1e211112de3b44ccaeaf71 Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Sun, 12 Mar 2023 23:00:03 +0100 Subject: [PATCH] efi: earlycon: Reprobe after parsing config tables Commit 732ea9db9d8a ("efi: libstub: Move screen_info handling to common code") reorganized the earlycon handling so that all architectures pass the screen_info data via a EFI config table instead of populating struct screen_info directly, as the latter is only possible when the EFI stub is baked into the kernel (and not into the decompressor). However, this means that struct screen_info may not have been populated yet by the time the earlycon probe takes place, and this results in a non-functional early console. So let's probe again right after parsing the config tables and populating struct screen_info. Note that this means that earlycon output starts a bit later than before, and so it may fail to capture issues that occur while doing the early EFI initialization. Fixes: 732ea9db9d8a ("efi: libstub: Move screen_info handling to common code") Reported-by: Shawn Guo Tested-by: Shawn Guo Signed-off-by: Ard Biesheuvel --- drivers/firmware/efi/earlycon.c | 16 +++++++++++++--- drivers/firmware/efi/efi-init.c | 3 +++ include/linux/efi.h | 1 + 3 files changed, 17 insertions(+), 3 deletions(-) diff --git a/drivers/firmware/efi/earlycon.c b/drivers/firmware/efi/earlycon.c index f54e6fd..f80a9af 100644 --- a/drivers/firmware/efi/earlycon.c +++ b/drivers/firmware/efi/earlycon.c @@ -215,6 +215,14 @@ efi_earlycon_write(struct console *con, const char *str, unsigned int num) } } +static bool __initdata fb_probed; + +void __init efi_earlycon_reprobe(void) +{ + if (fb_probed) + setup_earlycon("efifb"); +} + static int __init efi_earlycon_setup(struct earlycon_device *device, const char *opt) { @@ -222,15 +230,17 @@ static int __init efi_earlycon_setup(struct earlycon_device *device, u16 xres, yres; u32 i; - if (screen_info.orig_video_isVGA != VIDEO_TYPE_EFI) + fb_wb = opt && !strcmp(opt, "ram"); + + if (screen_info.orig_video_isVGA != VIDEO_TYPE_EFI) { + fb_probed = true; return -ENODEV; + } fb_base = screen_info.lfb_base; if (screen_info.capabilities & VIDEO_CAPABILITY_64BIT_BASE) fb_base |= (u64)screen_info.ext_lfb_base << 32; - fb_wb = opt && !strcmp(opt, "ram"); - si = &screen_info; xres = si->lfb_width; yres = si->lfb_height; diff --git a/drivers/firmware/efi/efi-init.c b/drivers/firmware/efi/efi-init.c index 2c16080..ef0820f 100644 --- a/drivers/firmware/efi/efi-init.c +++ b/drivers/firmware/efi/efi-init.c @@ -72,6 +72,9 @@ static void __init init_screen_info(void) if (memblock_is_map_memory(screen_info.lfb_base)) memblock_mark_nomap(screen_info.lfb_base, screen_info.lfb_size); + + if (IS_ENABLED(CONFIG_EFI_EARLYCON)) + efi_earlycon_reprobe(); } } diff --git a/include/linux/efi.h b/include/linux/efi.h index 04a733f..7aa62c9 100644 --- a/include/linux/efi.h +++ b/include/linux/efi.h @@ -693,6 +693,7 @@ efi_guid_to_str(efi_guid_t *guid, char *out) } extern void efi_init (void); +extern void efi_earlycon_reprobe(void); #ifdef CONFIG_EFI extern void efi_enter_virtual_mode (void); /* switch EFI to virtual mode, if possible */ #else -- 2.7.4