Merge tag 'pm-4.8-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management fixes from Rafael Wysocki:
 "Two hibernation fixes allowing it to work with the recently added
  randomization of the kernel identity mapping base on x86-64 and one
  cpufreq driver regression fix.

  Specifics:

   - Fix the x86 identity mapping creation helpers to avoid the
     assumption that the base address of the mapping will always be
     aligned at the PGD level, as it may be aligned at the PUD level if
     address space randomization is enabled (Rafael Wysocki).

   - Fix the hibernation core to avoid executing tracing functions
     before restoring the processor state completely during resume
     (Thomas Garnier).

   - Fix a recently introduced regression in the powernv cpufreq driver
     that causes it to crash due to an out-of-bounds array access
     (Akshay Adiga)"

* tag 'pm-4.8-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  PM / hibernate: Restore processor state before using per-CPU variables
  x86/power/64: Always create temporary identity mapping correctly
  cpufreq: powernv: Fix crash in gpstate_timer_handler()

5 files changed, 36 insertions, 14 deletions

diff --git a/arch/x86/include/asm/init.h b/arch/x86/include/asm/init.h
index 223042086f4e..737da62bfeb0 100644
--- a/arch/x86/include/asm/init.h
+++ b/arch/x86/include/asm/init.h
@@ -5,10 +5,10 @@ struct x86_mapping_info {
 	void *(*alloc_pgt_page)(void *); /* allocate buf for page table */
 	void *context;			 /* context for alloc_pgt_page */
 	unsigned long pmd_flag;		 /* page flag for PMD entry */
-	bool kernel_mapping;		 /* kernel mapping or ident mapping */
+	unsigned long offset;		 /* ident mapping offset */
 };
 
 int kernel_ident_mapping_init(struct x86_mapping_info *info, pgd_t *pgd_page,
-				unsigned long addr, unsigned long end);
+				unsigned long pstart, unsigned long pend);
 
 #endif /* _ASM_X86_INIT_H */
diff --git a/arch/x86/mm/ident_map.c b/arch/x86/mm/ident_map.c
index ec21796ac5fd..4473cb4f8b90 100644
--- a/arch/x86/mm/ident_map.c
+++ b/arch/x86/mm/ident_map.c
@@ -3,15 +3,17 @@
  * included by both the compressed kernel and the regular kernel.
  */
 
-static void ident_pmd_init(unsigned long pmd_flag, pmd_t *pmd_page,
+static void ident_pmd_init(struct x86_mapping_info *info, pmd_t *pmd_page,
 			   unsigned long addr, unsigned long end)
 {
 	addr &= PMD_MASK;
 	for (; addr < end; addr += PMD_SIZE) {
 		pmd_t *pmd = pmd_page + pmd_index(addr);
 
-		if (!pmd_present(*pmd))
-			set_pmd(pmd, __pmd(addr | pmd_flag));
+		if (pmd_present(*pmd))
+			continue;
+
+		set_pmd(pmd, __pmd((addr - info->offset) | info->pmd_flag));
 	}
 }
 
@@ -30,13 +32,13 @@ static int ident_pud_init(struct x86_mapping_info *info, pud_t *pud_page,
 
 		if (pud_present(*pud)) {
 			pmd = pmd_offset(pud, 0);
-			ident_pmd_init(info->pmd_flag, pmd, addr, next);
+			ident_pmd_init(info, pmd, addr, next);
 			continue;
 		}
 		pmd = (pmd_t *)info->alloc_pgt_page(info->context);
 		if (!pmd)
 			return -ENOMEM;
-		ident_pmd_init(info->pmd_flag, pmd, addr, next);
+		ident_pmd_init(info, pmd, addr, next);
 		set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE));
 	}
 
@@ -44,14 +46,15 @@ static int ident_pud_init(struct x86_mapping_info *info, pud_t *pud_page,
 }
 
 int kernel_ident_mapping_init(struct x86_mapping_info *info, pgd_t *pgd_page,
-			      unsigned long addr, unsigned long end)
+			      unsigned long pstart, unsigned long pend)
 {
+	unsigned long addr = pstart + info->offset;
+	unsigned long end = pend + info->offset;
 	unsigned long next;
 	int result;
-	int off = info->kernel_mapping ? pgd_index(__PAGE_OFFSET) : 0;
 
 	for (; addr < end; addr = next) {
-		pgd_t *pgd = pgd_page + pgd_index(addr) + off;
+		pgd_t *pgd = pgd_page + pgd_index(addr);
 		pud_t *pud;
 
 		next = (addr & PGDIR_MASK) + PGDIR_SIZE;
diff --git a/arch/x86/power/hibernate_64.c b/arch/x86/power/hibernate_64.c
index f0b5f2d402af..a3e3ccc87138 100644
--- a/arch/x86/power/hibernate_64.c
+++ b/arch/x86/power/hibernate_64.c
@@ -87,7 +87,7 @@ static int set_up_temporary_mappings(void)
 	struct x86_mapping_info info = {
 		.alloc_pgt_page	= alloc_pgt_page,
 		.pmd_flag	= __PAGE_KERNEL_LARGE_EXEC,
-		.kernel_mapping = true,
+		.offset		= __PAGE_OFFSET,
 	};
 	unsigned long mstart, mend;
 	pgd_t *pgd;
diff --git a/drivers/cpufreq/powernv-cpufreq.c b/drivers/cpufreq/powernv-cpufreq.c
index 87796e0864e9..d3ffde806629 100644
--- a/drivers/cpufreq/powernv-cpufreq.c
+++ b/drivers/cpufreq/powernv-cpufreq.c
@@ -145,11 +145,30 @@ static struct powernv_pstate_info {
 /* Use following macros for conversions between pstate_id and index */
 static inline int idx_to_pstate(unsigned int i)
 {
+	if (unlikely(i >= powernv_pstate_info.nr_pstates)) {
+		pr_warn_once("index %u is out of bound\n", i);
+		return powernv_freqs[powernv_pstate_info.nominal].driver_data;
+	}
+
 	return powernv_freqs[i].driver_data;
 }
 
 static inline unsigned int pstate_to_idx(int pstate)
 {
+	int min = powernv_freqs[powernv_pstate_info.min].driver_data;
+	int max = powernv_freqs[powernv_pstate_info.max].driver_data;
+
+	if (min > 0) {
+		if (unlikely((pstate < max) || (pstate > min))) {
+			pr_warn_once("pstate %d is out of bound\n", pstate);
+			return powernv_pstate_info.nominal;
+		}
+	} else {
+		if (unlikely((pstate > max) || (pstate < min))) {
+			pr_warn_once("pstate %d is out of bound\n", pstate);
+			return powernv_pstate_info.nominal;
+		}
+	}
 	/*
 	 * abs() is deliberately used so that is works with
 	 * both monotonically increasing and decreasing
@@ -593,7 +612,7 @@ void gpstate_timer_handler(unsigned long data)
 	} else {
 		gpstate_idx = calc_global_pstate(gpstates->elapsed_time,
 						 gpstates->highest_lpstate_idx,
-						 freq_data.pstate_id);
+						 gpstates->last_lpstate_idx);
 	}
 
 	/*
diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c
index a881c6a7ba74..33c79b6105c5 100644
--- a/kernel/power/hibernate.c
+++ b/kernel/power/hibernate.c
@@ -300,12 +300,12 @@ static int create_image(int platform_mode)
 	save_processor_state();
 	trace_suspend_resume(TPS("machine_suspend"), PM_EVENT_HIBERNATE, true);
 	error = swsusp_arch_suspend();
+	/* Restore control flow magically appears here */
+	restore_processor_state();
 	trace_suspend_resume(TPS("machine_suspend"), PM_EVENT_HIBERNATE, false);
 	if (error)
 		printk(KERN_ERR "PM: Error %d creating hibernation image\n",
 			error);
-	/* Restore control flow magically appears here */
-	restore_processor_state();
 	if (!in_suspend)
 		events_check_enabled = false;