Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752239Ab3CXFPa (ORCPT ); Sun, 24 Mar 2013 01:15:30 -0400 Received: from terminus.zytor.com ([198.137.202.10]:60226 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750887Ab3CXFP1 (ORCPT ); Sun, 24 Mar 2013 01:15:27 -0400 Date: Sat, 23 Mar 2013 22:13:38 -0700 Message-Id: <201303240513.r2O5Dc2V025273@terminus.zytor.com> From: "H. Peter Anvin" To: Linus Torvalds Subject: [GIT PULL] x86 fixes for 3.9-rc4 Cc: , Andre Heider , Ben Hutchings , CQ Tang , Fenghua Yu , Frederic Crozat , "H. Peter Anvin" , "H. Peter Anvin" , Ingo Molnar , Josh Boyer , Lee@zytor.com, Chun-Yi , Lingzhu Xiang , Linux Kernel Mailing List , Matt Fleming , Matthew Garrett , Michael Schroeder , Mike Marciniszyn , Seiji Aguchi , Seth Forshee , Shaun Ruffell , Tetsuo Handa , Thomas Gleixner , Tony Luck X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.2.7 (terminus.zytor.com [127.0.0.1]); Sat, 23 Mar 2013 22:13:44 -0700 (PDT) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 13625 Lines: 419 Hi Linus, A collection of minor fixes, more EFI variables paranoia (anti-bricking) plus the ability to disable the pstore either as a runtime default or completely, due to bricking concerns. The following changes since commit a937536b868b8369b98967929045f1df54234323: Linux 3.9-rc3 (2013-03-17 15:59:32 -0700) are available in the git repository at: git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git x86/urgent for you to fetch changes up to b9726d9df8263fe756d2293ff01906f41f7d2776: Merge tag 'efi-for-3.9-rc4' into x86/urgent (2013-03-23 21:49:51 -0700) ---------------------------------------------------------------- Ben Hutchings (1): efivars: Fix check for CONFIG_EFI_VARS_PSTORE_DEFAULT_DISABLE CQ Tang (1): x86-64: Fix the failure case in copy_user_handle_tail() Fenghua Yu (1): x86-32, microcode_intel_early: Fix crash with CONFIG_DEBUG_VIRTUAL H. Peter Anvin (3): x86, microcode_intel_early: Mark apply_microcode_early() as cpuinit Merge tag 'efi-for-3.9-rc3' into x86/urgent Merge tag 'efi-for-3.9-rc4' into x86/urgent Matt Fleming (2): efivars: explicitly calculate length of VariableName efivars: Handle duplicate names from get_next_variable() Seth Forshee (2): efivars: Allow disabling use as a pstore backend efivars: Add module parameter to disable use as a pstore backend arch/x86/kernel/microcode_intel_early.c | 30 +++---- arch/x86/lib/usercopy_64.c | 4 +- drivers/firmware/Kconfig | 18 ++++ drivers/firmware/efivars.c | 150 ++++++++++++++++++++++---------- 4 files changed, 139 insertions(+), 63 deletions(-) diff --git a/arch/x86/kernel/microcode_intel_early.c b/arch/x86/kernel/microcode_intel_early.c index 7890bc8..d893e8e 100644 --- a/arch/x86/kernel/microcode_intel_early.c +++ b/arch/x86/kernel/microcode_intel_early.c @@ -90,13 +90,13 @@ microcode_phys(struct microcode_intel **mc_saved_tmp, struct microcode_intel ***mc_saved; mc_saved = (struct microcode_intel ***) - __pa_symbol(&mc_saved_data->mc_saved); + __pa_nodebug(&mc_saved_data->mc_saved); for (i = 0; i < mc_saved_data->mc_saved_count; i++) { struct microcode_intel *p; p = *(struct microcode_intel **) - __pa(mc_saved_data->mc_saved + i); - mc_saved_tmp[i] = (struct microcode_intel *)__pa(p); + __pa_nodebug(mc_saved_data->mc_saved + i); + mc_saved_tmp[i] = (struct microcode_intel *)__pa_nodebug(p); } } #endif @@ -562,7 +562,7 @@ scan_microcode(unsigned long start, unsigned long end, struct cpio_data cd; long offset = 0; #ifdef CONFIG_X86_32 - char *p = (char *)__pa_symbol(ucode_name); + char *p = (char *)__pa_nodebug(ucode_name); #else char *p = ucode_name; #endif @@ -630,8 +630,8 @@ static void __cpuinit print_ucode(struct ucode_cpu_info *uci) if (mc_intel == NULL) return; - delay_ucode_info_p = (int *)__pa_symbol(&delay_ucode_info); - current_mc_date_p = (int *)__pa_symbol(¤t_mc_date); + delay_ucode_info_p = (int *)__pa_nodebug(&delay_ucode_info); + current_mc_date_p = (int *)__pa_nodebug(¤t_mc_date); *delay_ucode_info_p = 1; *current_mc_date_p = mc_intel->hdr.date; @@ -659,8 +659,8 @@ static inline void __cpuinit print_ucode(struct ucode_cpu_info *uci) } #endif -static int apply_microcode_early(struct mc_saved_data *mc_saved_data, - struct ucode_cpu_info *uci) +static int __cpuinit apply_microcode_early(struct mc_saved_data *mc_saved_data, + struct ucode_cpu_info *uci) { struct microcode_intel *mc_intel; unsigned int val[2]; @@ -741,15 +741,15 @@ load_ucode_intel_bsp(void) #ifdef CONFIG_X86_32 struct boot_params *boot_params_p; - boot_params_p = (struct boot_params *)__pa_symbol(&boot_params); + boot_params_p = (struct boot_params *)__pa_nodebug(&boot_params); ramdisk_image = boot_params_p->hdr.ramdisk_image; ramdisk_size = boot_params_p->hdr.ramdisk_size; initrd_start_early = ramdisk_image; initrd_end_early = initrd_start_early + ramdisk_size; _load_ucode_intel_bsp( - (struct mc_saved_data *)__pa_symbol(&mc_saved_data), - (unsigned long *)__pa_symbol(&mc_saved_in_initrd), + (struct mc_saved_data *)__pa_nodebug(&mc_saved_data), + (unsigned long *)__pa_nodebug(&mc_saved_in_initrd), initrd_start_early, initrd_end_early, &uci); #else ramdisk_image = boot_params.hdr.ramdisk_image; @@ -772,10 +772,10 @@ void __cpuinit load_ucode_intel_ap(void) unsigned long *initrd_start_p; mc_saved_in_initrd_p = - (unsigned long *)__pa_symbol(mc_saved_in_initrd); - mc_saved_data_p = (struct mc_saved_data *)__pa_symbol(&mc_saved_data); - initrd_start_p = (unsigned long *)__pa_symbol(&initrd_start); - initrd_start_addr = (unsigned long)__pa_symbol(*initrd_start_p); + (unsigned long *)__pa_nodebug(mc_saved_in_initrd); + mc_saved_data_p = (struct mc_saved_data *)__pa_nodebug(&mc_saved_data); + initrd_start_p = (unsigned long *)__pa_nodebug(&initrd_start); + initrd_start_addr = (unsigned long)__pa_nodebug(*initrd_start_p); #else mc_saved_data_p = &mc_saved_data; mc_saved_in_initrd_p = mc_saved_in_initrd; diff --git a/arch/x86/lib/usercopy_64.c b/arch/x86/lib/usercopy_64.c index 05928aa..906fea3 100644 --- a/arch/x86/lib/usercopy_64.c +++ b/arch/x86/lib/usercopy_64.c @@ -74,10 +74,10 @@ copy_user_handle_tail(char *to, char *from, unsigned len, unsigned zerorest) char c; unsigned zero_len; - for (; len; --len) { + for (; len; --len, to++) { if (__get_user_nocheck(c, from++, sizeof(char))) break; - if (__put_user_nocheck(c, to++, sizeof(char))) + if (__put_user_nocheck(c, to, sizeof(char))) break; } diff --git a/drivers/firmware/Kconfig b/drivers/firmware/Kconfig index 9b00072..42c759a 100644 --- a/drivers/firmware/Kconfig +++ b/drivers/firmware/Kconfig @@ -53,6 +53,24 @@ config EFI_VARS Subsequent efibootmgr releases may be found at: +config EFI_VARS_PSTORE + bool "Register efivars backend for pstore" + depends on EFI_VARS && PSTORE + default y + help + Say Y here to enable use efivars as a backend to pstore. This + will allow writing console messages, crash dumps, or anything + else supported by pstore to EFI variables. + +config EFI_VARS_PSTORE_DEFAULT_DISABLE + bool "Disable using efivars as a pstore backend by default" + depends on EFI_VARS_PSTORE + default n + help + Saying Y here will disable the use of efivars as a storage + backend for pstore by default. This setting can be overridden + using the efivars module's pstore_disable parameter. + config EFI_PCDP bool "Console device selection via EFI PCDP or HCDP table" depends on ACPI && EFI && IA64 diff --git a/drivers/firmware/efivars.c b/drivers/firmware/efivars.c index fe62aa3..7acafb8 100644 --- a/drivers/firmware/efivars.c +++ b/drivers/firmware/efivars.c @@ -103,6 +103,11 @@ MODULE_VERSION(EFIVARS_VERSION); */ #define GUID_LEN 36 +static bool efivars_pstore_disable = + IS_ENABLED(CONFIG_EFI_VARS_PSTORE_DEFAULT_DISABLE); + +module_param_named(pstore_disable, efivars_pstore_disable, bool, 0644); + /* * The maximum size of VariableName + Data = 1024 * Therefore, it's reasonable to save that much @@ -165,6 +170,7 @@ efivar_create_sysfs_entry(struct efivars *efivars, static void efivar_update_sysfs_entries(struct work_struct *); static DECLARE_WORK(efivar_work, efivar_update_sysfs_entries); +static bool efivar_wq_enabled = true; /* Return the number of unicode characters in data */ static unsigned long @@ -1309,9 +1315,7 @@ static const struct inode_operations efivarfs_dir_inode_operations = { .create = efivarfs_create, }; -static struct pstore_info efi_pstore_info; - -#ifdef CONFIG_PSTORE +#ifdef CONFIG_EFI_VARS_PSTORE static int efi_pstore_open(struct pstore_info *psi) { @@ -1441,7 +1445,7 @@ static int efi_pstore_write(enum pstore_type_id type, spin_unlock_irqrestore(&efivars->lock, flags); - if (reason == KMSG_DUMP_OOPS) + if (reason == KMSG_DUMP_OOPS && efivar_wq_enabled) schedule_work(&efivar_work); *id = part; @@ -1514,38 +1518,6 @@ static int efi_pstore_erase(enum pstore_type_id type, u64 id, int count, return 0; } -#else -static int efi_pstore_open(struct pstore_info *psi) -{ - return 0; -} - -static int efi_pstore_close(struct pstore_info *psi) -{ - return 0; -} - -static ssize_t efi_pstore_read(u64 *id, enum pstore_type_id *type, int *count, - struct timespec *timespec, - char **buf, struct pstore_info *psi) -{ - return -1; -} - -static int efi_pstore_write(enum pstore_type_id type, - enum kmsg_dump_reason reason, u64 *id, - unsigned int part, int count, size_t size, - struct pstore_info *psi) -{ - return 0; -} - -static int efi_pstore_erase(enum pstore_type_id type, u64 id, int count, - struct timespec time, struct pstore_info *psi) -{ - return 0; -} -#endif static struct pstore_info efi_pstore_info = { .owner = THIS_MODULE, @@ -1557,6 +1529,24 @@ static struct pstore_info efi_pstore_info = { .erase = efi_pstore_erase, }; +static void efivar_pstore_register(struct efivars *efivars) +{ + efivars->efi_pstore_info = efi_pstore_info; + efivars->efi_pstore_info.buf = kmalloc(4096, GFP_KERNEL); + if (efivars->efi_pstore_info.buf) { + efivars->efi_pstore_info.bufsize = 1024; + efivars->efi_pstore_info.data = efivars; + spin_lock_init(&efivars->efi_pstore_info.buf_lock); + pstore_register(&efivars->efi_pstore_info); + } +} +#else +static void efivar_pstore_register(struct efivars *efivars) +{ + return; +} +#endif + static ssize_t efivar_create(struct file *filp, struct kobject *kobj, struct bin_attribute *bin_attr, char *buf, loff_t pos, size_t count) @@ -1716,6 +1706,31 @@ static bool variable_is_present(efi_char16_t *variable_name, efi_guid_t *vendor) return found; } +/* + * Returns the size of variable_name, in bytes, including the + * terminating NULL character, or variable_name_size if no NULL + * character is found among the first variable_name_size bytes. + */ +static unsigned long var_name_strnsize(efi_char16_t *variable_name, + unsigned long variable_name_size) +{ + unsigned long len; + efi_char16_t c; + + /* + * The variable name is, by definition, a NULL-terminated + * string, so make absolutely sure that variable_name_size is + * the value we expect it to be. If not, return the real size. + */ + for (len = 2; len <= variable_name_size; len += sizeof(c)) { + c = variable_name[(len / sizeof(c)) - 1]; + if (!c) + break; + } + + return min(len, variable_name_size); +} + static void efivar_update_sysfs_entries(struct work_struct *work) { struct efivars *efivars = &__efivars; @@ -1756,10 +1771,13 @@ static void efivar_update_sysfs_entries(struct work_struct *work) if (!found) { kfree(variable_name); break; - } else + } else { + variable_name_size = var_name_strnsize(variable_name, + variable_name_size); efivar_create_sysfs_entry(efivars, variable_name_size, variable_name, &vendor); + } } } @@ -1958,6 +1976,35 @@ void unregister_efivars(struct efivars *efivars) } EXPORT_SYMBOL_GPL(unregister_efivars); +/* + * Print a warning when duplicate EFI variables are encountered and + * disable the sysfs workqueue since the firmware is buggy. + */ +static void dup_variable_bug(efi_char16_t *s16, efi_guid_t *vendor_guid, + unsigned long len16) +{ + size_t i, len8 = len16 / sizeof(efi_char16_t); + char *s8; + + /* + * Disable the workqueue since the algorithm it uses for + * detecting new variables won't work with this buggy + * implementation of GetNextVariableName(). + */ + efivar_wq_enabled = false; + + s8 = kzalloc(len8, GFP_KERNEL); + if (!s8) + return; + + for (i = 0; i < len8; i++) + s8[i] = s16[i]; + + printk(KERN_WARNING "efivars: duplicate variable: %s-%pUl\n", + s8, vendor_guid); + kfree(s8); +} + int register_efivars(struct efivars *efivars, const struct efivar_operations *ops, struct kobject *parent_kobj) @@ -2006,6 +2053,24 @@ int register_efivars(struct efivars *efivars, &vendor_guid); switch (status) { case EFI_SUCCESS: + variable_name_size = var_name_strnsize(variable_name, + variable_name_size); + + /* + * Some firmware implementations return the + * same variable name on multiple calls to + * get_next_variable(). Terminate the loop + * immediately as there is no guarantee that + * we'll ever see a different variable name, + * and may end up looping here forever. + */ + if (variable_is_present(variable_name, &vendor_guid)) { + dup_variable_bug(variable_name, &vendor_guid, + variable_name_size); + status = EFI_NOT_FOUND; + break; + } + efivar_create_sysfs_entry(efivars, variable_name_size, variable_name, @@ -2025,15 +2090,8 @@ int register_efivars(struct efivars *efivars, if (error) unregister_efivars(efivars); - efivars->efi_pstore_info = efi_pstore_info; - - efivars->efi_pstore_info.buf = kmalloc(4096, GFP_KERNEL); - if (efivars->efi_pstore_info.buf) { - efivars->efi_pstore_info.bufsize = 1024; - efivars->efi_pstore_info.data = efivars; - spin_lock_init(&efivars->efi_pstore_info.buf_lock); - pstore_register(&efivars->efi_pstore_info); - } + if (!efivars_pstore_disable) + efivar_pstore_register(efivars); register_filesystem(&efivarfs_type); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/