diff --git a/Documentation/ABI/testing/sysfs-power b/Documentation/ABI/testing/sysfs-power index 2f813d644c69..18b7dc929234 100644 --- a/Documentation/ABI/testing/sysfs-power +++ b/Documentation/ABI/testing/sysfs-power @@ -99,7 +99,7 @@ Description: this file, the suspend image will be as small as possible. Reading from this file will display the current image size - limit, which is set to 500 MB by default. + limit, which is set to around 2/5 of available RAM by default. What: /sys/power/pm_trace Date: August 2006 diff --git a/Documentation/power/swsusp.txt b/Documentation/power/swsusp.txt index cc87adf44c0a..236d1fb13640 100644 --- a/Documentation/power/swsusp.txt +++ b/Documentation/power/swsusp.txt @@ -56,7 +56,7 @@ If you want to limit the suspend image size to N bytes, do echo N > /sys/power/image_size -before suspend (it is limited to 500 MB by default). +before suspend (it is limited to around 2/5 of available RAM by default). . The resume process checks for the presence of the resume device, if found, it then checks the contents for the hibernation image signature. diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 1a0be022f91d..e8de5de1057f 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -2422,7 +2422,7 @@ menu "Power management and ACPI options" config ARCH_HIBERNATION_HEADER def_bool y - depends on X86_64 && HIBERNATION + depends on HIBERNATION source "kernel/power/Kconfig" diff --git a/arch/x86/include/asm/suspend.h b/arch/x86/include/asm/suspend.h index ecffe81ff65c..a892494ca5e4 100644 --- a/arch/x86/include/asm/suspend.h +++ b/arch/x86/include/asm/suspend.h @@ -4,3 +4,11 @@ #else # include #endif +extern unsigned long restore_jump_address __visible; +extern unsigned long jump_address_phys; +extern unsigned long restore_cr3 __visible; +extern unsigned long temp_pgt __visible; +extern unsigned long relocated_restore_code __visible; +extern int relocate_restore_code(void); +/* Defined in hibernate_asm_32/64.S */ +extern asmlinkage __visible int restore_image(void); diff --git a/arch/x86/include/asm/suspend_32.h b/arch/x86/include/asm/suspend_32.h index 8be6afb58471..fdbd9d7b7bca 100644 --- a/arch/x86/include/asm/suspend_32.h +++ b/arch/x86/include/asm/suspend_32.h @@ -32,4 +32,8 @@ struct saved_context { unsigned long return_address; } __attribute__((packed)); +/* routines for saving/restoring kernel state */ +extern char core_restore_code[]; +extern char restore_registers[]; + #endif /* _ASM_X86_SUSPEND_32_H */ diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index b4866badb235..90ecc108bc8a 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -1251,7 +1251,7 @@ void __init setup_arch(char **cmdline_p) x86_init.hyper.guest_late_init(); e820__reserve_resources(); - e820__register_nosave_regions(max_low_pfn); + e820__register_nosave_regions(max_pfn); x86_init.resources.reserve_resources(); diff --git a/arch/x86/power/Makefile b/arch/x86/power/Makefile index a4701389562c..37923d715741 100644 --- a/arch/x86/power/Makefile +++ b/arch/x86/power/Makefile @@ -7,4 +7,4 @@ nostackp := $(call cc-option, -fno-stack-protector) CFLAGS_cpu.o := $(nostackp) obj-$(CONFIG_PM_SLEEP) += cpu.o -obj-$(CONFIG_HIBERNATION) += hibernate_$(BITS).o hibernate_asm_$(BITS).o +obj-$(CONFIG_HIBERNATION) += hibernate_$(BITS).o hibernate_asm_$(BITS).o hibernate.o diff --git a/arch/x86/power/hibernate.c b/arch/x86/power/hibernate.c new file mode 100644 index 000000000000..bcddf09b5aa3 --- /dev/null +++ b/arch/x86/power/hibernate.c @@ -0,0 +1,248 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Hibernation support for x86 + * + * Copyright (c) 2007 Rafael J. Wysocki + * Copyright (c) 2002 Pavel Machek + * Copyright (c) 2001 Patrick Mochel + */ +#include +#include +#include +#include +#include + +#include + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +/* + * Address to jump to in the last phase of restore in order to get to the image + * kernel's text (this value is passed in the image header). + */ +unsigned long restore_jump_address __visible; +unsigned long jump_address_phys; + +/* + * Value of the cr3 register from before the hibernation (this value is passed + * in the image header). + */ +unsigned long restore_cr3 __visible; +unsigned long temp_pgt __visible; +unsigned long relocated_restore_code __visible; + +/** + * pfn_is_nosave - check if given pfn is in the 'nosave' section + */ +int pfn_is_nosave(unsigned long pfn) +{ + unsigned long nosave_begin_pfn; + unsigned long nosave_end_pfn; + + nosave_begin_pfn = __pa_symbol(&__nosave_begin) >> PAGE_SHIFT; + nosave_end_pfn = PAGE_ALIGN(__pa_symbol(&__nosave_end)) >> PAGE_SHIFT; + + return pfn >= nosave_begin_pfn && pfn < nosave_end_pfn; +} + + +#define MD5_DIGEST_SIZE 16 + +struct restore_data_record { + unsigned long jump_address; + unsigned long jump_address_phys; + unsigned long cr3; + unsigned long magic; + u8 e820_digest[MD5_DIGEST_SIZE]; +}; + +#if IS_BUILTIN(CONFIG_CRYPTO_MD5) +/** + * get_e820_md5 - calculate md5 according to given e820 table + * + * @table: the e820 table to be calculated + * @buf: the md5 result to be stored to + */ +static int get_e820_md5(struct e820_table *table, void *buf) +{ + struct crypto_shash *tfm; + struct shash_desc *desc; + int size; + int ret = 0; + + tfm = crypto_alloc_shash("md5", 0, 0); + if (IS_ERR(tfm)) + return -ENOMEM; + + desc = kmalloc(sizeof(struct shash_desc) + crypto_shash_descsize(tfm), + GFP_KERNEL); + if (!desc) { + ret = -ENOMEM; + goto free_tfm; + } + + desc->tfm = tfm; + desc->flags = 0; + + size = offsetof(struct e820_table, entries) + + sizeof(struct e820_entry) * table->nr_entries; + + if (crypto_shash_digest(desc, (u8 *)table, size, buf)) + ret = -EINVAL; + + kzfree(desc); + +free_tfm: + crypto_free_shash(tfm); + return ret; +} + +static int hibernation_e820_save(void *buf) +{ + return get_e820_md5(e820_table_firmware, buf); +} + +static bool hibernation_e820_mismatch(void *buf) +{ + int ret; + u8 result[MD5_DIGEST_SIZE]; + + memset(result, 0, MD5_DIGEST_SIZE); + /* If there is no digest in suspend kernel, let it go. */ + if (!memcmp(result, buf, MD5_DIGEST_SIZE)) + return false; + + ret = get_e820_md5(e820_table_firmware, result); + if (ret) + return true; + + return memcmp(result, buf, MD5_DIGEST_SIZE) ? true : false; +} +#else +static int hibernation_e820_save(void *buf) +{ + return 0; +} + +static bool hibernation_e820_mismatch(void *buf) +{ + /* If md5 is not builtin for restore kernel, let it go. */ + return false; +} +#endif + +#ifdef CONFIG_X86_64 +#define RESTORE_MAGIC 0x23456789ABCDEF01UL +#else +#define RESTORE_MAGIC 0x12345678UL +#endif + +/** + * arch_hibernation_header_save - populate the architecture specific part + * of a hibernation image header + * @addr: address to save the data at + */ +int arch_hibernation_header_save(void *addr, unsigned int max_size) +{ + struct restore_data_record *rdr = addr; + + if (max_size < sizeof(struct restore_data_record)) + return -EOVERFLOW; + rdr->magic = RESTORE_MAGIC; + rdr->jump_address = (unsigned long)restore_registers; + rdr->jump_address_phys = __pa_symbol(restore_registers); + + /* + * The restore code fixes up CR3 and CR4 in the following sequence: + * + * [in hibernation asm] + * 1. CR3 <= temporary page tables + * 2. CR4 <= mmu_cr4_features (from the kernel that restores us) + * 3. CR3 <= rdr->cr3 + * 4. CR4 <= mmu_cr4_features (from us, i.e. the image kernel) + * [in restore_processor_state()] + * 5. CR4 <= saved CR4 + * 6. CR3 <= saved CR3 + * + * Our mmu_cr4_features has CR4.PCIDE=0, and toggling + * CR4.PCIDE while CR3's PCID bits are nonzero is illegal, so + * rdr->cr3 needs to point to valid page tables but must not + * have any of the PCID bits set. + */ + rdr->cr3 = restore_cr3 & ~CR3_PCID_MASK; + + return hibernation_e820_save(rdr->e820_digest); +} + +/** + * arch_hibernation_header_restore - read the architecture specific data + * from the hibernation image header + * @addr: address to read the data from + */ +int arch_hibernation_header_restore(void *addr) +{ + struct restore_data_record *rdr = addr; + + if (rdr->magic != RESTORE_MAGIC) { + pr_crit("Unrecognized hibernate image header format!\n"); + return -EINVAL; + } + + restore_jump_address = rdr->jump_address; + jump_address_phys = rdr->jump_address_phys; + restore_cr3 = rdr->cr3; + + if (hibernation_e820_mismatch(rdr->e820_digest)) { + pr_crit("Hibernate inconsistent memory map detected!\n"); + return -ENODEV; + } + + return 0; +} + +int relocate_restore_code(void) +{ + pgd_t *pgd; + p4d_t *p4d; + pud_t *pud; + pmd_t *pmd; + pte_t *pte; + + relocated_restore_code = get_safe_page(GFP_ATOMIC); + if (!relocated_restore_code) + return -ENOMEM; + + memcpy((void *)relocated_restore_code, core_restore_code, PAGE_SIZE); + + /* Make the page containing the relocated code executable */ + pgd = (pgd_t *)__va(read_cr3_pa()) + + pgd_index(relocated_restore_code); + p4d = p4d_offset(pgd, relocated_restore_code); + if (p4d_large(*p4d)) { + set_p4d(p4d, __p4d(p4d_val(*p4d) & ~_PAGE_NX)); + goto out; + } + pud = pud_offset(p4d, relocated_restore_code); + if (pud_large(*pud)) { + set_pud(pud, __pud(pud_val(*pud) & ~_PAGE_NX)); + goto out; + } + pmd = pmd_offset(pud, relocated_restore_code); + if (pmd_large(*pmd)) { + set_pmd(pmd, __pmd(pmd_val(*pmd) & ~_PAGE_NX)); + goto out; + } + pte = pte_offset_kernel(pmd, relocated_restore_code); + set_pte(pte, __pte(pte_val(*pte) & ~_PAGE_NX)); +out: + __flush_tlb_all(); + return 0; +} diff --git a/arch/x86/power/hibernate_32.c b/arch/x86/power/hibernate_32.c index afc4ed7b1578..15695e30f982 100644 --- a/arch/x86/power/hibernate_32.c +++ b/arch/x86/power/hibernate_32.c @@ -14,9 +14,7 @@ #include #include #include - -/* Defined in hibernate_asm_32.S */ -extern int restore_image(void); +#include /* Pointer to the temporary resume page tables */ pgd_t *resume_pg_dir; @@ -145,6 +143,32 @@ static inline void resume_init_first_level_page_table(pgd_t *pg_dir) #endif } +static int set_up_temporary_text_mapping(pgd_t *pgd_base) +{ + pgd_t *pgd; + pmd_t *pmd; + pte_t *pte; + + pgd = pgd_base + pgd_index(restore_jump_address); + + pmd = resume_one_md_table_init(pgd); + if (!pmd) + return -ENOMEM; + + if (boot_cpu_has(X86_FEATURE_PSE)) { + set_pmd(pmd + pmd_index(restore_jump_address), + __pmd((jump_address_phys & PMD_MASK) | pgprot_val(PAGE_KERNEL_LARGE_EXEC))); + } else { + pte = resume_one_page_table_init(pmd); + if (!pte) + return -ENOMEM; + set_pte(pte + pte_index(restore_jump_address), + __pte((jump_address_phys & PAGE_MASK) | pgprot_val(PAGE_KERNEL_EXEC))); + } + + return 0; +} + asmlinkage int swsusp_arch_resume(void) { int error; @@ -154,22 +178,22 @@ asmlinkage int swsusp_arch_resume(void) return -ENOMEM; resume_init_first_level_page_table(resume_pg_dir); + + error = set_up_temporary_text_mapping(resume_pg_dir); + if (error) + return error; + error = resume_physical_mapping_init(resume_pg_dir); if (error) return error; + temp_pgt = __pa(resume_pg_dir); + + error = relocate_restore_code(); + if (error) + return error; + /* We have got enough memory and from now on we cannot recover */ restore_image(); return 0; } - -/* - * pfn_is_nosave - check if given pfn is in the 'nosave' section - */ - -int pfn_is_nosave(unsigned long pfn) -{ - unsigned long nosave_begin_pfn = __pa_symbol(&__nosave_begin) >> PAGE_SHIFT; - unsigned long nosave_end_pfn = PAGE_ALIGN(__pa_symbol(&__nosave_end)) >> PAGE_SHIFT; - return (pfn >= nosave_begin_pfn) && (pfn < nosave_end_pfn); -} diff --git a/arch/x86/power/hibernate_64.c b/arch/x86/power/hibernate_64.c index f8e3b668d20b..239f424ccb29 100644 --- a/arch/x86/power/hibernate_64.c +++ b/arch/x86/power/hibernate_64.c @@ -26,26 +26,6 @@ #include #include -/* Defined in hibernate_asm_64.S */ -extern asmlinkage __visible int restore_image(void); - -/* - * Address to jump to in the last phase of restore in order to get to the image - * kernel's text (this value is passed in the image header). - */ -unsigned long restore_jump_address __visible; -unsigned long jump_address_phys; - -/* - * Value of the cr3 register from before the hibernation (this value is passed - * in the image header). - */ -unsigned long restore_cr3 __visible; - -unsigned long temp_level4_pgt __visible; - -unsigned long relocated_restore_code __visible; - static int set_up_temporary_text_mapping(pgd_t *pgd) { pmd_t *pmd; @@ -141,46 +121,7 @@ static int set_up_temporary_mappings(void) return result; } - temp_level4_pgt = __pa(pgd); - return 0; -} - -static int relocate_restore_code(void) -{ - pgd_t *pgd; - p4d_t *p4d; - pud_t *pud; - pmd_t *pmd; - pte_t *pte; - - relocated_restore_code = get_safe_page(GFP_ATOMIC); - if (!relocated_restore_code) - return -ENOMEM; - - memcpy((void *)relocated_restore_code, core_restore_code, PAGE_SIZE); - - /* Make the page containing the relocated code executable */ - pgd = (pgd_t *)__va(read_cr3_pa()) + - pgd_index(relocated_restore_code); - p4d = p4d_offset(pgd, relocated_restore_code); - if (p4d_large(*p4d)) { - set_p4d(p4d, __p4d(p4d_val(*p4d) & ~_PAGE_NX)); - goto out; - } - pud = pud_offset(p4d, relocated_restore_code); - if (pud_large(*pud)) { - set_pud(pud, __pud(pud_val(*pud) & ~_PAGE_NX)); - goto out; - } - pmd = pmd_offset(pud, relocated_restore_code); - if (pmd_large(*pmd)) { - set_pmd(pmd, __pmd(pmd_val(*pmd) & ~_PAGE_NX)); - goto out; - } - pte = pte_offset_kernel(pmd, relocated_restore_code); - set_pte(pte, __pte(pte_val(*pte) & ~_PAGE_NX)); -out: - __flush_tlb_all(); + temp_pgt = __pa(pgd); return 0; } @@ -200,166 +141,3 @@ asmlinkage int swsusp_arch_resume(void) restore_image(); return 0; } - -/* - * pfn_is_nosave - check if given pfn is in the 'nosave' section - */ - -int pfn_is_nosave(unsigned long pfn) -{ - unsigned long nosave_begin_pfn = __pa_symbol(&__nosave_begin) >> PAGE_SHIFT; - unsigned long nosave_end_pfn = PAGE_ALIGN(__pa_symbol(&__nosave_end)) >> PAGE_SHIFT; - return (pfn >= nosave_begin_pfn) && (pfn < nosave_end_pfn); -} - -#define MD5_DIGEST_SIZE 16 - -struct restore_data_record { - unsigned long jump_address; - unsigned long jump_address_phys; - unsigned long cr3; - unsigned long magic; - u8 e820_digest[MD5_DIGEST_SIZE]; -}; - -#define RESTORE_MAGIC 0x23456789ABCDEF01UL - -#if IS_BUILTIN(CONFIG_CRYPTO_MD5) -/** - * get_e820_md5 - calculate md5 according to given e820 table - * - * @table: the e820 table to be calculated - * @buf: the md5 result to be stored to - */ -static int get_e820_md5(struct e820_table *table, void *buf) -{ - struct crypto_shash *tfm; - struct shash_desc *desc; - int size; - int ret = 0; - - tfm = crypto_alloc_shash("md5", 0, 0); - if (IS_ERR(tfm)) - return -ENOMEM; - - desc = kmalloc(sizeof(struct shash_desc) + crypto_shash_descsize(tfm), - GFP_KERNEL); - if (!desc) { - ret = -ENOMEM; - goto free_tfm; - } - - desc->tfm = tfm; - desc->flags = 0; - - size = offsetof(struct e820_table, entries) + - sizeof(struct e820_entry) * table->nr_entries; - - if (crypto_shash_digest(desc, (u8 *)table, size, buf)) - ret = -EINVAL; - - kzfree(desc); - -free_tfm: - crypto_free_shash(tfm); - return ret; -} - -static void hibernation_e820_save(void *buf) -{ - get_e820_md5(e820_table_firmware, buf); -} - -static bool hibernation_e820_mismatch(void *buf) -{ - int ret; - u8 result[MD5_DIGEST_SIZE]; - - memset(result, 0, MD5_DIGEST_SIZE); - /* If there is no digest in suspend kernel, let it go. */ - if (!memcmp(result, buf, MD5_DIGEST_SIZE)) - return false; - - ret = get_e820_md5(e820_table_firmware, result); - if (ret) - return true; - - return memcmp(result, buf, MD5_DIGEST_SIZE) ? true : false; -} -#else -static void hibernation_e820_save(void *buf) -{ -} - -static bool hibernation_e820_mismatch(void *buf) -{ - /* If md5 is not builtin for restore kernel, let it go. */ - return false; -} -#endif - -/** - * arch_hibernation_header_save - populate the architecture specific part - * of a hibernation image header - * @addr: address to save the data at - */ -int arch_hibernation_header_save(void *addr, unsigned int max_size) -{ - struct restore_data_record *rdr = addr; - - if (max_size < sizeof(struct restore_data_record)) - return -EOVERFLOW; - rdr->jump_address = (unsigned long)restore_registers; - rdr->jump_address_phys = __pa_symbol(restore_registers); - - /* - * The restore code fixes up CR3 and CR4 in the following sequence: - * - * [in hibernation asm] - * 1. CR3 <= temporary page tables - * 2. CR4 <= mmu_cr4_features (from the kernel that restores us) - * 3. CR3 <= rdr->cr3 - * 4. CR4 <= mmu_cr4_features (from us, i.e. the image kernel) - * [in restore_processor_state()] - * 5. CR4 <= saved CR4 - * 6. CR3 <= saved CR3 - * - * Our mmu_cr4_features has CR4.PCIDE=0, and toggling - * CR4.PCIDE while CR3's PCID bits are nonzero is illegal, so - * rdr->cr3 needs to point to valid page tables but must not - * have any of the PCID bits set. - */ - rdr->cr3 = restore_cr3 & ~CR3_PCID_MASK; - - rdr->magic = RESTORE_MAGIC; - - hibernation_e820_save(rdr->e820_digest); - - return 0; -} - -/** - * arch_hibernation_header_restore - read the architecture specific data - * from the hibernation image header - * @addr: address to read the data from - */ -int arch_hibernation_header_restore(void *addr) -{ - struct restore_data_record *rdr = addr; - - restore_jump_address = rdr->jump_address; - jump_address_phys = rdr->jump_address_phys; - restore_cr3 = rdr->cr3; - - if (rdr->magic != RESTORE_MAGIC) { - pr_crit("Unrecognized hibernate image header format!\n"); - return -EINVAL; - } - - if (hibernation_e820_mismatch(rdr->e820_digest)) { - pr_crit("Hibernate inconsistent memory map detected!\n"); - return -ENODEV; - } - - return 0; -} diff --git a/arch/x86/power/hibernate_asm_32.S b/arch/x86/power/hibernate_asm_32.S index 6e56815e13a0..6fe383002125 100644 --- a/arch/x86/power/hibernate_asm_32.S +++ b/arch/x86/power/hibernate_asm_32.S @@ -12,6 +12,7 @@ #include #include #include +#include .text @@ -24,13 +25,30 @@ ENTRY(swsusp_arch_suspend) pushfl popl saved_context_eflags + /* save cr3 */ + movl %cr3, %eax + movl %eax, restore_cr3 + + FRAME_BEGIN call swsusp_save + FRAME_END ret +ENDPROC(swsusp_arch_suspend) ENTRY(restore_image) + /* prepare to jump to the image kernel */ + movl restore_jump_address, %ebx + movl restore_cr3, %ebp + movl mmu_cr4_features, %ecx - movl resume_pg_dir, %eax - subl $__PAGE_OFFSET, %eax + + /* jump to relocated restore code */ + movl relocated_restore_code, %eax + jmpl *%eax + +/* code below has been relocated to a safe page */ +ENTRY(core_restore_code) + movl temp_pgt, %eax movl %eax, %cr3 jecxz 1f # cr4 Pentium and higher, skip if zero @@ -49,7 +67,7 @@ copy_loop: movl pbe_address(%edx), %esi movl pbe_orig_address(%edx), %edi - movl $1024, %ecx + movl $(PAGE_SIZE >> 2), %ecx rep movsl @@ -58,10 +76,13 @@ copy_loop: .p2align 4,,7 done: + jmpl *%ebx + + /* code below belongs to the image kernel */ + .align PAGE_SIZE +ENTRY(restore_registers) /* go back to the original page tables */ - movl $swapper_pg_dir, %eax - subl $__PAGE_OFFSET, %eax - movl %eax, %cr3 + movl %ebp, %cr3 movl mmu_cr4_features, %ecx jecxz 1f # cr4 Pentium and higher, skip if zero movl %ecx, %cr4; # turn PGE back on @@ -82,4 +103,8 @@ done: xorl %eax, %eax + /* tell the hibernation core that we've just restored the memory */ + movl %eax, in_suspend + ret +ENDPROC(restore_registers) diff --git a/arch/x86/power/hibernate_asm_64.S b/arch/x86/power/hibernate_asm_64.S index fd369a6e9ff8..3008baa2fa95 100644 --- a/arch/x86/power/hibernate_asm_64.S +++ b/arch/x86/power/hibernate_asm_64.S @@ -59,7 +59,7 @@ ENTRY(restore_image) movq restore_cr3(%rip), %r9 /* prepare to switch to temporary page tables */ - movq temp_level4_pgt(%rip), %rax + movq temp_pgt(%rip), %rax movq mmu_cr4_features(%rip), %rbx /* prepare to copy image data to their original locations */ diff --git a/drivers/acpi/acpi_lpit.c b/drivers/acpi/acpi_lpit.c index cf4fc0161164..e43cb71b6972 100644 --- a/drivers/acpi/acpi_lpit.c +++ b/drivers/acpi/acpi_lpit.c @@ -117,11 +117,17 @@ static void lpit_update_residency(struct lpit_residency_info *info, if (!info->iomem_addr) return; + if (!(acpi_gbl_FADT.flags & ACPI_FADT_LOW_POWER_S0)) + return; + /* Silently fail, if cpuidle attribute group is not present */ sysfs_add_file_to_group(&cpu_subsys.dev_root->kobj, &dev_attr_low_power_idle_system_residency_us.attr, "cpuidle"); } else if (info->gaddr.space_id == ACPI_ADR_SPACE_FIXED_HARDWARE) { + if (!(acpi_gbl_FADT.flags & ACPI_FADT_LOW_POWER_S0)) + return; + /* Silently fail, if cpuidle attribute group is not present */ sysfs_add_file_to_group(&cpu_subsys.dev_root->kobj, &dev_attr_low_power_idle_cpu_residency_us.attr, diff --git a/kernel/power/process.c b/kernel/power/process.c index 7381d49a44db..4b6a54da7e65 100644 --- a/kernel/power/process.c +++ b/kernel/power/process.c @@ -96,7 +96,7 @@ static int try_to_freeze_tasks(bool user_only) if (wq_busy) show_workqueue_state(); - if (!wakeup) { + if (!wakeup || pm_debug_messages_on) { read_lock(&tasklist_lock); for_each_process_thread(g, p) { if (p != current && !freezer_should_skip(p)