5 files changed, 75 insertions, 71 deletions
diff --git a/arch/um/kernel/irq.c b/arch/um/kernel/irq.c
index 338450741aac..a4991746f5ea 100644
--- a/arch/um/kernel/irq.c
+++ b/arch/um/kernel/irq.c
@@ -52,7 +52,7 @@ struct irq_entry {
 	bool sigio_workaround;
 };
 
-static DEFINE_SPINLOCK(irq_lock);
+static DEFINE_RAW_SPINLOCK(irq_lock);
 static LIST_HEAD(active_fds);
 static DECLARE_BITMAP(irqs_allocated, UM_LAST_SIGNAL_IRQ);
 static bool irqs_suspended;
@@ -257,7 +257,7 @@ static struct irq_entry *get_irq_entry_by_fd(int fd)
 	return NULL;
 }
 
-static void free_irq_entry(struct irq_entry *to_free, bool remove)
+static void remove_irq_entry(struct irq_entry *to_free, bool remove)
 {
 	if (!to_free)
 		return;
@@ -265,7 +265,6 @@ static void free_irq_entry(struct irq_entry *to_free, bool remove)
 	if (remove)
 		os_del_epoll_fd(to_free->fd);
 	list_del(&to_free->list);
-	kfree(to_free);
 }
 
 static bool update_irq_entry(struct irq_entry *entry)
@@ -286,17 +285,19 @@ static bool update_irq_entry(struct irq_entry *entry)
 	return false;
 }
 
-static void update_or_free_irq_entry(struct irq_entry *entry)
+static struct irq_entry *update_or_remove_irq_entry(struct irq_entry *entry)
 {
-	if (!update_irq_entry(entry))
-		free_irq_entry(entry, false);
+	if (update_irq_entry(entry))
+		return NULL;
+	remove_irq_entry(entry, false);
+	return entry;
 }
 
 static int activate_fd(int irq, int fd, enum um_irq_type type, void *dev_id,
 		       void (*timetravel_handler)(int, int, void *,
 						  struct time_travel_event *))
 {
-	struct irq_entry *irq_entry;
+	struct irq_entry *irq_entry, *to_free = NULL;
 	int err, events = os_event_mask(type);
 	unsigned long flags;
 
@@ -304,9 +305,10 @@ static int activate_fd(int irq, int fd, enum um_irq_type type, void *dev_id,
 	if (err < 0)
 		goto out;
 
-	spin_lock_irqsave(&irq_lock, flags);
+	raw_spin_lock_irqsave(&irq_lock, flags);
 	irq_entry = get_irq_entry_by_fd(fd);
 	if (irq_entry) {
+already:
 		/* cannot register the same FD twice with the same type */
 		if (WARN_ON(irq_entry->reg[type].events)) {
 			err = -EALREADY;
@@ -316,11 +318,22 @@ static int activate_fd(int irq, int fd, enum um_irq_type type, void *dev_id,
 		/* temporarily disable to avoid IRQ-side locking */
 		os_del_epoll_fd(fd);
 	} else {
-		irq_entry = kzalloc(sizeof(*irq_entry), GFP_ATOMIC);
-		if (!irq_entry) {
-			err = -ENOMEM;
-			goto out_unlock;
+		struct irq_entry *new;
+
+		/* don't restore interrupts */
+		raw_spin_unlock(&irq_lock);
+		new = kzalloc(sizeof(*irq_entry), GFP_ATOMIC);
+		if (!new) {
+			local_irq_restore(flags);
+			return -ENOMEM;
 		}
+		raw_spin_lock(&irq_lock);
+		irq_entry = get_irq_entry_by_fd(fd);
+		if (irq_entry) {
+			to_free = new;
+			goto already;
+		}
+		irq_entry = new;
 		irq_entry->fd = fd;
 		list_add_tail(&irq_entry->list, &active_fds);
 		maybe_sigio_broken(fd);
@@ -339,12 +352,11 @@ static int activate_fd(int irq, int fd, enum um_irq_type type, void *dev_id,
 #endif
 
 	WARN_ON(!update_irq_entry(irq_entry));
-	spin_unlock_irqrestore(&irq_lock, flags);
-
-	return 0;
+	err = 0;
 out_unlock:
-	spin_unlock_irqrestore(&irq_lock, flags);
+	raw_spin_unlock_irqrestore(&irq_lock, flags);
 out:
+	kfree(to_free);
 	return err;
 }
 
@@ -358,19 +370,20 @@ void free_irq_by_fd(int fd)
 	struct irq_entry *to_free;
 	unsigned long flags;
 
-	spin_lock_irqsave(&irq_lock, flags);
+	raw_spin_lock_irqsave(&irq_lock, flags);
 	to_free = get_irq_entry_by_fd(fd);
-	free_irq_entry(to_free, true);
-	spin_unlock_irqrestore(&irq_lock, flags);
+	remove_irq_entry(to_free, true);
+	raw_spin_unlock_irqrestore(&irq_lock, flags);
+	kfree(to_free);
 }
 EXPORT_SYMBOL(free_irq_by_fd);
 
 static void free_irq_by_irq_and_dev(unsigned int irq, void *dev)
 {
-	struct irq_entry *entry;
+	struct irq_entry *entry, *to_free = NULL;
 	unsigned long flags;
 
-	spin_lock_irqsave(&irq_lock, flags);
+	raw_spin_lock_irqsave(&irq_lock, flags);
 	list_for_each_entry(entry, &active_fds, list) {
 		enum um_irq_type i;
 
@@ -386,12 +399,13 @@ static void free_irq_by_irq_and_dev(unsigned int irq, void *dev)
 
 			os_del_epoll_fd(entry->fd);
 			reg->events = 0;
-			update_or_free_irq_entry(entry);
+			to_free = update_or_remove_irq_entry(entry);
 			goto out;
 		}
 	}
 out:
-	spin_unlock_irqrestore(&irq_lock, flags);
+	raw_spin_unlock_irqrestore(&irq_lock, flags);
+	kfree(to_free);
 }
 
 void deactivate_fd(int fd, int irqnum)
@@ -402,7 +416,7 @@ void deactivate_fd(int fd, int irqnum)
 
 	os_del_epoll_fd(fd);
 
-	spin_lock_irqsave(&irq_lock, flags);
+	raw_spin_lock_irqsave(&irq_lock, flags);
 	entry = get_irq_entry_by_fd(fd);
 	if (!entry)
 		goto out;
@@ -414,9 +428,10 @@ void deactivate_fd(int fd, int irqnum)
 			entry->reg[i].events = 0;
 	}
 
-	update_or_free_irq_entry(entry);
+	entry = update_or_remove_irq_entry(entry);
 out:
-	spin_unlock_irqrestore(&irq_lock, flags);
+	raw_spin_unlock_irqrestore(&irq_lock, flags);
+	kfree(entry);
 
 	ignore_sigio_fd(fd);
 }
@@ -546,7 +561,7 @@ void um_irqs_suspend(void)
 
 	irqs_suspended = true;
 
-	spin_lock_irqsave(&irq_lock, flags);
+	raw_spin_lock_irqsave(&irq_lock, flags);
 	list_for_each_entry(entry, &active_fds, list) {
 		enum um_irq_type t;
 		bool clear = true;
@@ -579,7 +594,7 @@ void um_irqs_suspend(void)
 				!__ignore_sigio_fd(entry->fd);
 		}
 	}
-	spin_unlock_irqrestore(&irq_lock, flags);
+	raw_spin_unlock_irqrestore(&irq_lock, flags);
 }
 
 void um_irqs_resume(void)
@@ -588,7 +603,7 @@ void um_irqs_resume(void)
 	unsigned long flags;
 
 
-	spin_lock_irqsave(&irq_lock, flags);
+	raw_spin_lock_irqsave(&irq_lock, flags);
 	list_for_each_entry(entry, &active_fds, list) {
 		if (entry->suspended) {
 			int err = os_set_fd_async(entry->fd);
@@ -602,7 +617,7 @@ void um_irqs_resume(void)
 			}
 		}
 	}
-	spin_unlock_irqrestore(&irq_lock, flags);
+	raw_spin_unlock_irqrestore(&irq_lock, flags);
 
 	irqs_suspended = false;
 	send_sigio_to_self();
@@ -613,7 +628,7 @@ static int normal_irq_set_wake(struct irq_data *d, unsigned int on)
 	struct irq_entry *entry;
 	unsigned long flags;
 
-	spin_lock_irqsave(&irq_lock, flags);
+	raw_spin_lock_irqsave(&irq_lock, flags);
 	list_for_each_entry(entry, &active_fds, list) {
 		enum um_irq_type t;
 
@@ -628,7 +643,7 @@ static int normal_irq_set_wake(struct irq_data *d, unsigned int on)
 		}
 	}
 unlock:
-	spin_unlock_irqrestore(&irq_lock, flags);
+	raw_spin_unlock_irqrestore(&irq_lock, flags);
 	return 0;
 }
 #else
diff --git a/arch/um/kernel/load_file.c b/arch/um/kernel/load_file.c
index 5cecd0e291fb..cb9d178ab7d8 100644
--- a/arch/um/kernel/load_file.c
+++ b/arch/um/kernel/load_file.c
@@ -48,9 +48,7 @@ void *uml_load_file(const char *filename, unsigned long long *size)
 		return NULL;
 	}
 
-	area = memblock_alloc(*size, SMP_CACHE_BYTES);
-	if (!area)
-		panic("%s: Failed to allocate %llu bytes\n", __func__, *size);
+	area = memblock_alloc_or_panic(*size, SMP_CACHE_BYTES);
 
 	if (__uml_load_file(filename, area, *size)) {
 		memblock_free(area, *size);
diff --git a/arch/um/kernel/mem.c b/arch/um/kernel/mem.c
index 53248ed04771..befed230aac2 100644
--- a/arch/um/kernel/mem.c
+++ b/arch/um/kernel/mem.c
@@ -9,7 +9,6 @@
 #include <linux/mm.h>
 #include <linux/swap.h>
 #include <linux/slab.h>
-#include <asm/fixmap.h>
 #include <asm/page.h>
 #include <asm/pgalloc.h>
 #include <as-layout.h>
@@ -74,6 +73,7 @@ void __init mem_init(void)
 	kmalloc_ok = 1;
 }
 
+#if IS_ENABLED(CONFIG_ARCH_REUSE_HOST_VSYSCALL_AREA)
 /*
  * Create a page table and place a pointer to it in a middle page
  * directory entry.
@@ -152,7 +152,6 @@ static void __init fixrange_init(unsigned long start, unsigned long end,
 
 static void __init fixaddr_user_init( void)
 {
-#ifdef CONFIG_ARCH_REUSE_HOST_VSYSCALL_AREA
 	long size = FIXADDR_USER_END - FIXADDR_USER_START;
 	pte_t *pte;
 	phys_t p;
@@ -174,13 +173,12 @@ static void __init fixaddr_user_init( void)
 		pte = virt_to_kpte(vaddr);
 		pte_set_val(*pte, p, PAGE_READONLY);
 	}
-#endif
 }
+#endif
 
 void __init paging_init(void)
 {
 	unsigned long max_zone_pfn[MAX_NR_ZONES] = { 0 };
-	unsigned long vaddr;
 
 	empty_zero_page = (unsigned long *) memblock_alloc_low(PAGE_SIZE,
 							       PAGE_SIZE);
@@ -191,14 +189,9 @@ void __init paging_init(void)
 	max_zone_pfn[ZONE_NORMAL] = end_iomem >> PAGE_SHIFT;
 	free_area_init(max_zone_pfn);
 
-	/*
-	 * Fixed mappings, only the page table structure has to be
-	 * created - mappings will be set by set_fixmap():
-	 */
-	vaddr = __fix_to_virt(__end_of_fixed_addresses - 1) & PMD_MASK;
-	fixrange_init(vaddr, FIXADDR_TOP, swapper_pg_dir);
-
+#if IS_ENABLED(CONFIG_ARCH_REUSE_HOST_VSYSCALL_AREA)
 	fixaddr_user_init();
+#endif
 }
 
 /*
@@ -214,14 +207,13 @@ void free_initmem(void)
 
 pgd_t *pgd_alloc(struct mm_struct *mm)
 {
-	pgd_t *pgd = (pgd_t *)__get_free_page(GFP_KERNEL);
+	pgd_t *pgd = __pgd_alloc(mm, 0);
 
-	if (pgd) {
-		memset(pgd, 0, USER_PTRS_PER_PGD * sizeof(pgd_t));
+	if (pgd)
 		memcpy(pgd + USER_PTRS_PER_PGD,
 		       swapper_pg_dir + USER_PTRS_PER_PGD,
 		       (PTRS_PER_PGD - USER_PTRS_PER_PGD) * sizeof(pgd_t));
-	}
+
 	return pgd;
 }
 
diff --git a/arch/um/kernel/process.c b/arch/um/kernel/process.c
index 30bdc0a87dc8..0cd6fad3d908 100644
--- a/arch/um/kernel/process.c
+++ b/arch/um/kernel/process.c
@@ -191,7 +191,15 @@ void initial_thread_cb(void (*proc)(void *), void *arg)
 int arch_dup_task_struct(struct task_struct *dst,
 			 struct task_struct *src)
 {
-	memcpy(dst, src, arch_task_struct_size);
+	/* init_task is not dynamically sized (missing FPU state) */
+	if (unlikely(src == &init_task)) {
+		memcpy(dst, src, sizeof(init_task));
+		memset((void *)dst + sizeof(init_task), 0,
+		       arch_task_struct_size - sizeof(init_task));
+	} else {
+		memcpy(dst, src, arch_task_struct_size);
+	}
+
 	return 0;
 }
 
@@ -213,14 +221,6 @@ int __uml_cant_sleep(void) {
 	/* Is in_interrupt() really needed? */
 }
 
-int user_context(unsigned long sp)
-{
-	unsigned long stack;
-
-	stack = sp & (PAGE_MASK << CONFIG_KERNEL_STACK_ORDER);
-	return stack != (unsigned long) current_thread_info();
-}
-
 extern exitcall_t __uml_exitcall_begin, __uml_exitcall_end;
 
 void do_uml_exitcalls(void)
diff --git a/arch/um/kernel/um_arch.c b/arch/um/kernel/um_arch.c
index 8037a967225d..8be91974e786 100644
--- a/arch/um/kernel/um_arch.c
+++ b/arch/um/kernel/um_arch.c
@@ -264,7 +264,7 @@ EXPORT_SYMBOL(end_iomem);
 
 #define MIN_VMALLOC (32 * 1024 * 1024)
 
-static void parse_host_cpu_flags(char *line)
+static void __init parse_host_cpu_flags(char *line)
 {
 	int i;
 	for (i = 0; i < 32*NCAPINTS; i++) {
@@ -272,7 +272,8 @@ static void parse_host_cpu_flags(char *line)
 			set_cpu_cap(&boot_cpu_data, i);
 	}
 }
-static void parse_cache_line(char *line)
+
+static void __init parse_cache_line(char *line)
 {
 	long res;
 	char *to_parse = strstr(line, ":");
@@ -288,7 +289,7 @@ static void parse_cache_line(char *line)
 	}
 }
 
-static unsigned long get_top_address(char **envp)
+static unsigned long __init get_top_address(char **envp)
 {
 	unsigned long top_addr = (unsigned long) &top_addr;
 	int i;
@@ -376,9 +377,8 @@ int __init linux_main(int argc, char **argv, char **envp)
 	iomem_size = (iomem_size + PAGE_SIZE - 1) & PAGE_MASK;
 
 	max_physmem = TASK_SIZE - uml_physmem - iomem_size - MIN_VMALLOC;
-
-	if (physmem_size + iomem_size > max_physmem) {
-		physmem_size = max_physmem - iomem_size;
+	if (physmem_size > max_physmem) {
+		physmem_size = max_physmem;
 		os_info("Physical memory size shrunk to %llu bytes\n",
 			physmem_size);
 	}
@@ -440,25 +440,24 @@ void __init arch_cpu_finalize_init(void)
 	os_check_bugs();
 }
 
-void apply_seal_endbr(s32 *start, s32 *end, struct module *mod)
+void apply_seal_endbr(s32 *start, s32 *end)
 {
 }
 
-void apply_retpolines(s32 *start, s32 *end, struct module *mod)
+void apply_retpolines(s32 *start, s32 *end)
 {
 }
 
-void apply_returns(s32 *start, s32 *end, struct module *mod)
+void apply_returns(s32 *start, s32 *end)
 {
 }
 
 void apply_fineibt(s32 *start_retpoline, s32 *end_retpoline,
-		   s32 *start_cfi, s32 *end_cfi, struct module *mod)
+		   s32 *start_cfi, s32 *end_cfi)
 {
 }
 
-void apply_alternatives(struct alt_instr *start, struct alt_instr *end,
-			struct module *mod)
+void apply_alternatives(struct alt_instr *start, struct alt_instr *end)
 {
 }