From b84a64fad40637b1c9fa4f4dbf847a23e29e672b Mon Sep 17 00:00:00 2001 From: Eric Snowberg Date: Thu, 29 Nov 2018 18:12:20 +0100 Subject: [PATCH 1/2] x86/efi: Allocate e820 buffer before calling efi_exit_boot_service The following commit: d64934019f6c ("x86/efi: Use efi_exit_boot_services()") introduced a regression on systems with large memory maps causing them to hang on boot. The first "goto get_map" that was removed from exit_boot() ensured there was enough room for the memory map when efi_call_early(exit_boot_services) was called. This happens when (nr_desc > ARRAY_SIZE(params->e820_table). Chain of events: exit_boot() efi_exit_boot_services() efi_get_memory_map <- at this point the mm can't grow over 8 desc priv_func() exit_boot_func() allocate_e820ext() <- new mm grows over 8 desc from e820 alloc efi_call_early(exit_boot_services) <- mm key doesn't match so retry efi_call_early(get_memory_map) <- not enough room for new mm system hangs This patch allocates the e820 buffer before calling efi_exit_boot_services() and fixes the regression. [ mingo: minor cleanliness edits. ] Signed-off-by: Eric Snowberg Signed-off-by: Ard Biesheuvel Cc: Cc: Andy Lutomirski Cc: Arend van Spriel Cc: Bhupesh Sharma Cc: Borislav Petkov Cc: Dave Hansen Cc: Hans de Goede Cc: Joe Perches Cc: Jon Hunter Cc: Julien Thierry Cc: Linus Torvalds Cc: Marc Zyngier Cc: Matt Fleming Cc: Nathan Chancellor Cc: Peter Zijlstra Cc: Sai Praneeth Prakhya Cc: Sedat Dilek Cc: Thomas Gleixner Cc: YiFei Zhu Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/20181129171230.18699-2-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar --- arch/x86/boot/compressed/eboot.c | 65 ++++++++++++++++++++------------ 1 file changed, 41 insertions(+), 24 deletions(-) diff --git a/arch/x86/boot/compressed/eboot.c b/arch/x86/boot/compressed/eboot.c index 8b4c5e001157..544ac4fafd11 100644 --- a/arch/x86/boot/compressed/eboot.c +++ b/arch/x86/boot/compressed/eboot.c @@ -1,3 +1,4 @@ + /* ----------------------------------------------------------------------- * * Copyright 2011 Intel Corporation; author Matt Fleming @@ -634,37 +635,54 @@ static efi_status_t alloc_e820ext(u32 nr_desc, struct setup_data **e820ext, return status; } +static efi_status_t allocate_e820(struct boot_params *params, + struct setup_data **e820ext, + u32 *e820ext_size) +{ + unsigned long map_size, desc_size, buff_size; + struct efi_boot_memmap boot_map; + efi_memory_desc_t *map; + efi_status_t status; + __u32 nr_desc; + + boot_map.map = ↦ + boot_map.map_size = &map_size; + boot_map.desc_size = &desc_size; + boot_map.desc_ver = NULL; + boot_map.key_ptr = NULL; + boot_map.buff_size = &buff_size; + + status = efi_get_memory_map(sys_table, &boot_map); + if (status != EFI_SUCCESS) + return status; + + nr_desc = buff_size / desc_size; + + if (nr_desc > ARRAY_SIZE(params->e820_table)) { + u32 nr_e820ext = nr_desc - ARRAY_SIZE(params->e820_table); + + status = alloc_e820ext(nr_e820ext, e820ext, e820ext_size); + if (status != EFI_SUCCESS) + return status; + } + + return EFI_SUCCESS; +} + struct exit_boot_struct { struct boot_params *boot_params; struct efi_info *efi; - struct setup_data *e820ext; - __u32 e820ext_size; }; static efi_status_t exit_boot_func(efi_system_table_t *sys_table_arg, struct efi_boot_memmap *map, void *priv) { - static bool first = true; const char *signature; __u32 nr_desc; efi_status_t status; struct exit_boot_struct *p = priv; - if (first) { - nr_desc = *map->buff_size / *map->desc_size; - if (nr_desc > ARRAY_SIZE(p->boot_params->e820_table)) { - u32 nr_e820ext = nr_desc - - ARRAY_SIZE(p->boot_params->e820_table); - - status = alloc_e820ext(nr_e820ext, &p->e820ext, - &p->e820ext_size); - if (status != EFI_SUCCESS) - return status; - } - first = false; - } - signature = efi_is_64bit() ? EFI64_LOADER_SIGNATURE : EFI32_LOADER_SIGNATURE; memcpy(&p->efi->efi_loader_signature, signature, sizeof(__u32)); @@ -687,8 +705,8 @@ static efi_status_t exit_boot(struct boot_params *boot_params, void *handle) { unsigned long map_sz, key, desc_size, buff_size; efi_memory_desc_t *mem_map; - struct setup_data *e820ext; - __u32 e820ext_size; + struct setup_data *e820ext = NULL; + __u32 e820ext_size = 0; efi_status_t status; __u32 desc_version; struct efi_boot_memmap map; @@ -702,8 +720,10 @@ static efi_status_t exit_boot(struct boot_params *boot_params, void *handle) map.buff_size = &buff_size; priv.boot_params = boot_params; priv.efi = &boot_params->efi_info; - priv.e820ext = NULL; - priv.e820ext_size = 0; + + status = allocate_e820(boot_params, &e820ext, &e820ext_size); + if (status != EFI_SUCCESS) + return status; /* Might as well exit boot services now */ status = efi_exit_boot_services(sys_table, handle, &map, &priv, @@ -711,9 +731,6 @@ static efi_status_t exit_boot(struct boot_params *boot_params, void *handle) if (status != EFI_SUCCESS) return status; - e820ext = priv.e820ext; - e820ext_size = priv.e820ext_size; - /* Historic? */ boot_params->alt_mem_k = 32 * 1024; From 79c2206d369b87b19ac29cb47601059b6bf5c291 Mon Sep 17 00:00:00 2001 From: YiFei Zhu Date: Thu, 29 Nov 2018 18:12:30 +0100 Subject: [PATCH 2/2] x86/earlyprintk/efi: Fix infinite loop on some screen widths An affected screen resolution is 1366 x 768, which width is not divisible by 8, the default font width. On such screens, when longer lines are earlyprintk'ed, overflow-to-next-line can never trigger, due to the left-most x-coordinate of the next character always less than the screen width. Earlyprintk will infinite loop in trying to print the rest of the string but unable to, due to the line being full. This patch makes the trigger consider the right-most x-coordinate, instead of left-most, as the value to compare against the screen width threshold. Signed-off-by: YiFei Zhu Signed-off-by: Ard Biesheuvel Cc: Andy Lutomirski Cc: Arend van Spriel Cc: Bhupesh Sharma Cc: Borislav Petkov Cc: Dave Hansen Cc: Eric Snowberg Cc: Hans de Goede Cc: Joe Perches Cc: Jon Hunter Cc: Julien Thierry Cc: Linus Torvalds Cc: Marc Zyngier Cc: Matt Fleming Cc: Nathan Chancellor Cc: Peter Zijlstra Cc: Sai Praneeth Prakhya Cc: Sedat Dilek Cc: Thomas Gleixner Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/20181129171230.18699-12-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar --- arch/x86/platform/efi/early_printk.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/platform/efi/early_printk.c b/arch/x86/platform/efi/early_printk.c index 7476b3b097e1..7138bc7a265c 100644 --- a/arch/x86/platform/efi/early_printk.c +++ b/arch/x86/platform/efi/early_printk.c @@ -183,7 +183,7 @@ early_efi_write(struct console *con, const char *str, unsigned int num) num--; } - if (efi_x >= si->lfb_width) { + if (efi_x + font->width > si->lfb_width) { efi_x = 0; efi_y += font->height; }