From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeffrey Hugo Subject: [PATCH V2 4/4] x86/efi: Use efi_exit_boot_services() Date: Thu, 21 Jul 2016 14:28:14 -0600 Message-ID: <1469132894-17103-5-git-send-email-jhugo@codeaurora.org> References: <1469132894-17103-1-git-send-email-jhugo@codeaurora.org> Return-path: In-Reply-To: <1469132894-17103-1-git-send-email-jhugo-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org> Sender: linux-efi-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: matt-mF/unelCI9GS6iBeEJttW/XRex20P6io@public.gmane.org, linux-efi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, ard.biesheuvel-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org, mark.rutland-5wv7dgnIgG8@public.gmane.org, leif.lindholm-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org Cc: timur-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org, Jeffrey Hugo List-Id: linux-efi@vger.kernel.org The eboot code directly calls ExitBootServices. This is inadvisable, and the eboot code attempts allocations after calling ExitBootSerives which is not permitted per the spec. The efi_exit_boot_services() helper handles this scenario. Signed-off-by: Jeffrey Hugo --- arch/x86/boot/compressed/eboot.c | 130 ++++++++++++++++++++------------------- 1 file changed, 67 insertions(+), 63 deletions(-) diff --git a/arch/x86/boot/compressed/eboot.c b/arch/x86/boot/compressed/eboot.c index 9036ec9..3d3224d 100644 --- a/arch/x86/boot/compressed/eboot.c +++ b/arch/x86/boot/compressed/eboot.c @@ -1006,79 +1006,87 @@ static efi_status_t alloc_e820ext(u32 nr_desc, struct setup_data **e820ext, return status; } +struct exit_boot_struct { + struct boot_params *boot_params; + struct efi_info *efi; + struct setup_data *e820ext; + __u32 e820ext_size; + bool is64; +}; + +static efi_status_t exit_boot_func(efi_system_table_t *sys_table, + void *handle, + efi_memory_desc_t *memory_map, + unsigned long *map_size, + unsigned long *desc_size, + u32 *desc_ver, + unsigned long *mmap_key, + unsigned long buff_size, + 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 = buff_size / *desc_size; + if (nr_desc > ARRAY_SIZE(p->boot_params->e820_map)) { + u32 nr_e820ext = nr_desc - + ARRAY_SIZE(p->boot_params->e820_map); + + status = alloc_e820ext(nr_e820ext, &p->e820ext, + &p->e820ext_size); + if (status != EFI_SUCCESS) + return status; + } + first = false; + } + + signature = p->is64 ? EFI64_LOADER_SIGNATURE : EFI32_LOADER_SIGNATURE; + memcpy(&p->efi->efi_loader_signature, signature, sizeof(__u32)); + + p->efi->efi_systab = (unsigned long)sys_table; + p->efi->efi_memdesc_size = *desc_size; + p->efi->efi_memdesc_version = *desc_ver; + p->efi->efi_memmap = (unsigned long)memory_map; + p->efi->efi_memmap_size = *map_size; + +#ifdef CONFIG_X86_64 + p->efi->efi_systab_hi = (unsigned long)sys_table >> 32; + p->efi->efi_memmap_hi = (unsigned long)memory_map >> 32; +#endif + + return EFI_SUCCESS; +} + static efi_status_t exit_boot(struct boot_params *boot_params, void *handle, bool is64) { - struct efi_info *efi = &boot_params->efi_info; unsigned long map_sz, key, desc_size, buff_size; efi_memory_desc_t *mem_map; struct setup_data *e820ext; - const char *signature; __u32 e820ext_size; - __u32 nr_desc, prev_nr_desc; efi_status_t status; __u32 desc_version; - bool called_exit = false; - u8 nr_entries; - int i; - - nr_desc = 0; - e820ext = NULL; - e820ext_size = 0; + struct exit_boot_struct priv; -get_map: - status = efi_get_memory_map(sys_table, &mem_map, &map_sz, &desc_size, - &desc_version, &key, &buff_size); + priv.boot_params = boot_params; + priv.efi = &boot_params->efi_info; + priv.e820ext = NULL; + priv.e820ext_size = 0; + priv.is64 = is64; + /* Might as well exit boot services now */ + status = efi_exit_boot_services(sys_table, handle, &mem_map, + &map_sz, &desc_size, &desc_version, + &key, &priv, exit_boot_func); if (status != EFI_SUCCESS) return status; - prev_nr_desc = nr_desc; - nr_desc = map_sz / desc_size; - if (nr_desc > prev_nr_desc && - nr_desc > ARRAY_SIZE(boot_params->e820_map)) { - u32 nr_e820ext = nr_desc - ARRAY_SIZE(boot_params->e820_map); - - status = alloc_e820ext(nr_e820ext, &e820ext, &e820ext_size); - if (status != EFI_SUCCESS) - goto free_mem_map; - - efi_call_early(free_pool, mem_map); - goto get_map; /* Allocated memory, get map again */ - } - - signature = is64 ? EFI64_LOADER_SIGNATURE : EFI32_LOADER_SIGNATURE; - memcpy(&efi->efi_loader_signature, signature, sizeof(__u32)); - - efi->efi_systab = (unsigned long)sys_table; - efi->efi_memdesc_size = desc_size; - efi->efi_memdesc_version = desc_version; - efi->efi_memmap = (unsigned long)mem_map; - efi->efi_memmap_size = map_sz; - -#ifdef CONFIG_X86_64 - efi->efi_systab_hi = (unsigned long)sys_table >> 32; - efi->efi_memmap_hi = (unsigned long)mem_map >> 32; -#endif - - /* Might as well exit boot services now */ - status = efi_call_early(exit_boot_services, handle, key); - if (status != EFI_SUCCESS) { - /* - * ExitBootServices() will fail if any of the event - * handlers change the memory map. In which case, we - * must be prepared to retry, but only once so that - * we're guaranteed to exit on repeated failures instead - * of spinning forever. - */ - if (called_exit) - goto free_mem_map; - - called_exit = true; - efi_call_early(free_pool, mem_map); - goto get_map; - } - + e820ext = priv.e820ext; + e820ext_size = priv.e820ext_size; /* Historic? */ boot_params->alt_mem_k = 32 * 1024; @@ -1087,10 +1095,6 @@ get_map: return status; return EFI_SUCCESS; - -free_mem_map: - efi_call_early(free_pool, mem_map); - return status; } /* -- Qualcomm Datacenter Technologies as an affiliate of Qualcomm Technologies, Inc. Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.