Merge tag 'uml-for-linus-6.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/uml/linux

Pull UML updates from Richard Weinberger:

 - Lots of cleanups, mostly from Benjamin Berg and Tiwei Bie

 - Removal of unused code

 - Fix for sparse warnings

 - Cleanup around stub_exe()

* tag 'uml-for-linus-6.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/uml/linux: (68 commits)
  hostfs: Fix the NULL vs IS_ERR() bug for __filemap_get_folio()
  um: move thread info into task
  um: Always dump trace for specified task in show_stack
  um: vector: Do not use drvdata in release
  um: net: Do not use drvdata in release
  um: ubd: Do not use drvdata in release
  um: ubd: Initialize ubd's disk pointer in ubd_add
  um: virtio_uml: query the number of vqs if supported
  um: virtio_uml: fix call_fd IRQ allocation
  um: virtio_uml: send SET_MEM_TABLE message with the exact size
  um: remove broken double fault detection
  um: remove duplicate UM_NSEC_PER_SEC definition
  um: remove file sync for stub data
  um: always include kconfig.h and compiler-version.h
  um: set DONTDUMP and DONTFORK flags on KASAN shadow memory
  um: fix sparse warnings in signal code
  um: fix sparse warnings from regset refactor
  um: Remove double zero check
  um: fix stub exe build with CONFIG_GCOV
  um: Use os_set_pdeathsig helper in winch thread/process
  ...

arch/um/Kconfig

@@ -5,6 +5,7 @@ menu "UML-specific options"
 config UML
 	bool
 	default y
+	select ARCH_WANTS_DYNAMIC_TASK_STRUCT
 	select ARCH_HAS_CPU_FINALIZE_INIT
 	select ARCH_HAS_FORTIFY_SOURCE
 	select ARCH_HAS_GCOV_PROFILE_ALL
@@ -32,6 +33,8 @@ config UML
 	select HAVE_ARCH_VMAP_STACK
 	select HAVE_RUST
 	select ARCH_HAS_UBSAN
+	select HAVE_ARCH_TRACEHOOK
+	select THREAD_INFO_IN_TASK
 
 config MMU
 	bool
@@ -94,7 +97,7 @@ config MAY_HAVE_RUNTIME_DEPS
 
 config STATIC_LINK
 	bool "Force a static link"
-	depends on CC_CAN_LINK_STATIC_NO_RUNTIME_DEPS || !MAY_HAVE_RUNTIME_DEPS
+	depends on !MAY_HAVE_RUNTIME_DEPS
 	help
 	  This option gives you the ability to force a static link of UML.
 	  Normally, UML is linked as a shared binary.  This is inconvenient for
@@ -209,8 +212,8 @@ config MMAPPER
 
 config PGTABLE_LEVELS
 	int
-	default 3 if 3_LEVEL_PGTABLES
-	default 2
+	default 4 if 64BIT
+	default 2 if !64BIT
 
 config UML_TIME_TRAVEL_SUPPORT
 	bool
@@ -227,6 +230,21 @@ config UML_TIME_TRAVEL_SUPPORT
 
 	  It is safe to say Y, but you probably don't need this.
 
+config UML_MAX_USERSPACE_ITERATIONS
+	int
+	prompt "Maximum number of unscheduled userspace iterations"
+	default 10000
+	depends on UML_TIME_TRAVEL_SUPPORT
+	help
+	  In UML inf-cpu and ext time-travel mode userspace can run without being
+	  interrupted. This will eventually overwhelm the kernel and create OOM
+	  situations (mainly RCU not running). This setting specifies the number
+	  of kernel/userspace switches (minor/major page fault, signal or syscall)
+	  for the same userspace thread before the sched_clock is advanced by a
+	  jiffie to trigger scheduling.
+
+	  Setting it to zero disables the feature.
+
 config KASAN_SHADOW_OFFSET
 	hex
 	depends on KASAN

arch/um/Makefile

@@ -61,7 +61,8 @@ KBUILD_CFLAGS += $(CFLAGS) $(CFLAGS-y) -D__arch_um__ \
 	$(ARCH_INCLUDE) $(MODE_INCLUDE) -Dvmap=kernel_vmap	\
 	-Dlongjmp=kernel_longjmp -Dsetjmp=kernel_setjmp \
 	-Din6addr_loopback=kernel_in6addr_loopback \
-	-Din6addr_any=kernel_in6addr_any -Dstrrchr=kernel_strrchr
+	-Din6addr_any=kernel_in6addr_any -Dstrrchr=kernel_strrchr \
+	-D__close_range=kernel__close_range
 
 KBUILD_RUSTFLAGS += -Crelocation-model=pie
 
@@ -70,7 +71,9 @@ KBUILD_AFLAGS += $(ARCH_INCLUDE)
 USER_CFLAGS = $(patsubst $(KERNEL_DEFINES),,$(patsubst -I%,,$(KBUILD_CFLAGS))) \
 		$(ARCH_INCLUDE) $(MODE_INCLUDE) $(filter -I%,$(CFLAGS)) \
 		-D_FILE_OFFSET_BITS=64 -idirafter $(srctree)/include \
-		-idirafter $(objtree)/include -D__KERNEL__ -D__UM_HOST__
+		-idirafter $(objtree)/include -D__KERNEL__ -D__UM_HOST__ \
+		-include $(srctree)/include/linux/compiler-version.h \
+		-include $(srctree)/include/linux/kconfig.h
 
 #This will adjust *FLAGS accordingly to the platform.
 include $(srctree)/$(ARCH_DIR)/Makefile-os-Linux

arch/um/Makefile-skas

@@ -3,15 +3,15 @@
 # Licensed under the GPL
 #
 
-GPROF_OPT += -pg
+export UM_GPROF_OPT += -pg
 
 ifdef CONFIG_CC_IS_CLANG
-GCOV_OPT += -fprofile-instr-generate -fcoverage-mapping
+export UM_GCOV_OPT += -fprofile-instr-generate -fcoverage-mapping
 else
-GCOV_OPT += -fprofile-arcs -ftest-coverage
+export UM_GCOV_OPT += -fprofile-arcs -ftest-coverage
 endif
 
-CFLAGS-$(CONFIG_GCOV) += $(GCOV_OPT)
-CFLAGS-$(CONFIG_GPROF) += $(GPROF_OPT)
-LINK-$(CONFIG_GCOV) += $(GCOV_OPT)
-LINK-$(CONFIG_GPROF) += $(GPROF_OPT)
+CFLAGS-$(CONFIG_GCOV) += $(UM_GCOV_OPT)
+CFLAGS-$(CONFIG_GPROF) += $(UM_GPROF_OPT)
+LINK-$(CONFIG_GCOV) += $(UM_GCOV_OPT)
+LINK-$(CONFIG_GPROF) += $(UM_GPROF_OPT)

arch/um/configs/i386_defconfig

@@ -1,4 +1,3 @@
-CONFIG_3_LEVEL_PGTABLES=y
 # CONFIG_COMPACTION is not set
 CONFIG_BINFMT_MISC=m
 CONFIG_HOSTFS=y

arch/um/drivers/chan_user.c

@@ -161,6 +161,8 @@ static __noreturn int winch_thread(void *arg)
 	int count;
 	char c = 1;
 
+	os_set_pdeathsig();
+
 	pty_fd = data->pty_fd;
 	pipe_fd = data->pipe_fd;
 	count = write(pipe_fd, &c, sizeof(c));

arch/um/drivers/hostaudio_kern.c

@@ -48,6 +48,7 @@ MODULE_PARM_DESC(mixer, MIXER_HELP);
 #ifndef MODULE
 static int set_dsp(char *name, int *add)
 {
+	*add = 0;
 	dsp = name;
 	return 0;
 }
@@ -56,6 +57,7 @@ __uml_setup("dsp=", set_dsp, "dsp=<dsp device>\n" DSP_HELP);
 
 static int set_mixer(char *name, int *add)
 {
+	*add = 0;
 	mixer = name;
 	return 0;
 }

arch/um/drivers/net_kern.c

@@ -336,7 +336,7 @@ static struct platform_driver uml_net_driver = {
 
 static void net_device_release(struct device *dev)
 {
-	struct uml_net *device = dev_get_drvdata(dev);
+	struct uml_net *device = container_of(dev, struct uml_net, pdev.dev);
 	struct net_device *netdev = device->dev;
 	struct uml_net_private *lp = netdev_priv(netdev);
 

arch/um/drivers/ubd_kern.c

@@ -779,7 +779,7 @@ static int ubd_open_dev(struct ubd *ubd_dev)
 
 static void ubd_device_release(struct device *dev)
 {
-	struct ubd *ubd_dev = dev_get_drvdata(dev);
+	struct ubd *ubd_dev = container_of(dev, struct ubd, pdev.dev);
 
 	blk_mq_free_tag_set(&ubd_dev->tag_set);
 	*ubd_dev = ((struct ubd) DEFAULT_UBD);
@@ -898,6 +898,8 @@ static int ubd_add(int n, char **error_out)
 	if (err)
 		goto out_cleanup_disk;
 
+	ubd_dev->disk = disk;
+
 	return 0;
 
 out_cleanup_disk:
@@ -1499,6 +1501,7 @@ int io_thread(void *arg)
 {
 	int n, count, written, res;
 
+	os_set_pdeathsig();
 	os_fix_helper_signals();
 
 	while(1){

arch/um/drivers/vector_kern.c

@@ -815,7 +815,8 @@ static struct platform_driver uml_net_driver = {
 
 static void vector_device_release(struct device *dev)
 {
-	struct vector_device *device = dev_get_drvdata(dev);
+	struct vector_device *device =
+		container_of(dev, struct vector_device, pdev.dev);
 	struct net_device *netdev = device->dev;
 
 	list_del(&device->list);

arch/um/drivers/vhost_user.h

@@ -10,6 +10,7 @@
 /* Feature bits */
 #define VHOST_USER_F_PROTOCOL_FEATURES	30
 /* Protocol feature bits */
+#define VHOST_USER_PROTOCOL_F_MQ			0
 #define VHOST_USER_PROTOCOL_F_REPLY_ACK			3
 #define VHOST_USER_PROTOCOL_F_SLAVE_REQ			5
 #define VHOST_USER_PROTOCOL_F_CONFIG			9
@@ -23,7 +24,8 @@
 /* Supported transport features */
 #define VHOST_USER_SUPPORTED_F		BIT_ULL(VHOST_USER_F_PROTOCOL_FEATURES)
 /* Supported protocol features */
-#define VHOST_USER_SUPPORTED_PROTOCOL_F	(BIT_ULL(VHOST_USER_PROTOCOL_F_REPLY_ACK) | \
+#define VHOST_USER_SUPPORTED_PROTOCOL_F	(BIT_ULL(VHOST_USER_PROTOCOL_F_MQ) | \
+					 BIT_ULL(VHOST_USER_PROTOCOL_F_REPLY_ACK) | \
 					 BIT_ULL(VHOST_USER_PROTOCOL_F_SLAVE_REQ) | \
 					 BIT_ULL(VHOST_USER_PROTOCOL_F_CONFIG) | \
 					 BIT_ULL(VHOST_USER_PROTOCOL_F_INBAND_NOTIFICATIONS))

arch/um/drivers/virtio_uml.c

@@ -56,6 +56,7 @@ struct virtio_uml_device {
 	int sock, req_fd, irq;
 	u64 features;
 	u64 protocol_features;
+	u64 max_vqs;
 	u8 status;
 	u8 registered:1;
 	u8 suspended:1;
@@ -72,8 +73,6 @@ struct virtio_uml_vq_info {
 	bool suspended;
 };
 
-extern unsigned long long physmem_size, highmem;
-
 #define vu_err(vu_dev, ...)	dev_err(&(vu_dev)->pdev->dev, ##__VA_ARGS__)
 
 /* Vhost-user protocol */
@@ -343,6 +342,17 @@ static int vhost_user_set_protocol_features(struct virtio_uml_device *vu_dev,
 				   protocol_features);
 }
 
+static int vhost_user_get_queue_num(struct virtio_uml_device *vu_dev,
+				    u64 *queue_num)
+{
+	int rc = vhost_user_send_no_payload(vu_dev, true,
+			VHOST_USER_GET_QUEUE_NUM);
+
+	if (rc)
+		return rc;
+	return vhost_user_recv_u64(vu_dev, queue_num);
+}
+
 static void vhost_user_reply(struct virtio_uml_device *vu_dev,
 			     struct vhost_user_msg *msg, int response)
 {
@@ -516,6 +526,15 @@ static int vhost_user_init(struct virtio_uml_device *vu_dev)
 			return rc;
 	}
 
+	if (vu_dev->protocol_features &
+			BIT_ULL(VHOST_USER_PROTOCOL_F_MQ)) {
+		rc = vhost_user_get_queue_num(vu_dev, &vu_dev->max_vqs);
+		if (rc)
+			return rc;
+	} else {
+		vu_dev->max_vqs = U64_MAX;
+	}
+
 	return 0;
 }
 
@@ -625,7 +644,7 @@ static int vhost_user_set_mem_table(struct virtio_uml_device *vu_dev)
 {
 	struct vhost_user_msg msg = {
 		.header.request = VHOST_USER_SET_MEM_TABLE,
-		.header.size = sizeof(msg.payload.mem_regions),
+		.header.size = offsetof(typeof(msg.payload.mem_regions), regions[1]),
 		.payload.mem_regions.num = 1,
 	};
 	unsigned long reserved = uml_reserved - uml_physmem;
@@ -673,13 +692,6 @@ static int vhost_user_set_mem_table(struct virtio_uml_device *vu_dev)
 
 	if (rc < 0)
 		return rc;
-	if (highmem) {
-		msg.payload.mem_regions.num++;
-		rc = vhost_user_init_mem_region(__pa(end_iomem), highmem,
-				&fds[1], &msg.payload.mem_regions.regions[1]);
-		if (rc < 0)
-			return rc;
-	}
 
 	return vhost_user_send(vu_dev, false, &msg, fds,
 			       msg.payload.mem_regions.num);
@@ -897,7 +909,7 @@ static int vu_setup_vq_call_fd(struct virtio_uml_device *vu_dev,
 {
 	struct virtio_uml_vq_info *info = vq->priv;
 	int call_fds[2];
-	int rc;
+	int rc, irq;
 
 	/* no call FD needed/desired in this case */
 	if (vu_dev->protocol_features &
@@ -914,19 +926,23 @@ static int vu_setup_vq_call_fd(struct virtio_uml_device *vu_dev,
 		return rc;
 
 	info->call_fd = call_fds[0];
-	rc = um_request_irq(vu_dev->irq, info->call_fd, IRQ_READ,
-			    vu_interrupt, IRQF_SHARED, info->name, vq);
-	if (rc < 0)
+	irq = um_request_irq(vu_dev->irq, info->call_fd, IRQ_READ,
+			     vu_interrupt, IRQF_SHARED, info->name, vq);
+	if (irq < 0) {
+		rc = irq;
 		goto close_both;
+	}
 
 	rc = vhost_user_set_vring_call(vu_dev, vq->index, call_fds[1]);
 	if (rc)
 		goto release_irq;
 
+	vu_dev->irq = irq;
+
 	goto out;
 
 release_irq:
-	um_free_irq(vu_dev->irq, vq);
+	um_free_irq(irq, vq);
 close_both:
 	os_close_file(call_fds[0]);
 out:
@@ -1023,7 +1039,9 @@ static int vu_find_vqs(struct virtio_device *vdev, unsigned nvqs,
 	struct virtqueue *vq;
 
 	/* not supported for now */
-	if (WARN_ON(nvqs > 64))
+	if (WARN(nvqs > 64 || nvqs > vu_dev->max_vqs,
+		 "%d VQs requested, only up to 64 or %lld supported\n",
+		 nvqs, vu_dev->max_vqs))
 		return -EINVAL;
 
 	rc = vhost_user_set_mem_table(vu_dev);
@@ -1210,6 +1228,7 @@ static int virtio_uml_probe(struct platform_device *pdev)
 	vu_dev->vdev.id.vendor = VIRTIO_DEV_ANY_ID;
 	vu_dev->pdev = pdev;
 	vu_dev->req_fd = -1;
+	vu_dev->irq = UM_IRQ_ALLOC;
 
 	time_travel_propagate_time();
 

arch/um/include/asm/Kbuild

@@ -1,7 +1,6 @@
 # SPDX-License-Identifier: GPL-2.0
 generic-y += bug.h
 generic-y += compat.h
-generic-y += current.h
 generic-y += device.h
 generic-y += dma-mapping.h
 generic-y += emergency-restart.h

arch/um/include/asm/current.h

@@ -0,0 +1,23 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __ASM_CURRENT_H
+#define __ASM_CURRENT_H
+
+#include <linux/compiler.h>
+#include <linux/threads.h>
+
+#ifndef __ASSEMBLY__
+
+struct task_struct;
+extern struct task_struct *cpu_tasks[NR_CPUS];
+
+static __always_inline struct task_struct *get_current(void)
+{
+	return cpu_tasks[0];
+}
+
+
+#define current get_current()
+
+#endif /* __ASSEMBLY__ */
+
+#endif /* __ASM_CURRENT_H */

arch/um/include/asm/page.h

@@ -29,51 +29,35 @@ struct page;
 #define clear_user_page(page, vaddr, pg)	clear_page(page)
 #define copy_user_page(to, from, vaddr, pg)	copy_page(to, from)
 
-#if defined(CONFIG_3_LEVEL_PGTABLES) && !defined(CONFIG_64BIT)
-
-typedef struct { unsigned long pte; } pte_t;
-typedef struct { unsigned long pmd; } pmd_t;
-typedef struct { unsigned long pgd; } pgd_t;
-#define pte_val(p) ((p).pte)
-
-#define pte_get_bits(p, bits) ((p).pte & (bits))
-#define pte_set_bits(p, bits) ((p).pte |= (bits))
-#define pte_clear_bits(p, bits) ((p).pte &= ~(bits))
-#define pte_copy(to, from) ({ (to).pte = (from).pte; })
-#define pte_is_zero(p) (!((p).pte & ~_PAGE_NEWPAGE))
-#define pte_set_val(p, phys, prot) \
-	({ (p).pte = (phys) | pgprot_val(prot); })
-
-#define pmd_val(x)	((x).pmd)
-#define __pmd(x) ((pmd_t) { (x) } )
-
-typedef unsigned long long phys_t;
-
-#else
-
 typedef struct { unsigned long pte; } pte_t;
 typedef struct { unsigned long pgd; } pgd_t;
 
-#ifdef CONFIG_3_LEVEL_PGTABLES
+#if CONFIG_PGTABLE_LEVELS > 2
+
 typedef struct { unsigned long pmd; } pmd_t;
 #define pmd_val(x)	((x).pmd)
 #define __pmd(x) ((pmd_t) { (x) } )
-#endif
+
+#if CONFIG_PGTABLE_LEVELS > 3
+
+typedef struct { unsigned long pud; } pud_t;
+#define pud_val(x)	((x).pud)
+#define __pud(x) ((pud_t) { (x) } )
+
+#endif /* CONFIG_PGTABLE_LEVELS > 3 */
+#endif /* CONFIG_PGTABLE_LEVELS > 2 */
 
 #define pte_val(x)	((x).pte)
 
-
 #define pte_get_bits(p, bits) ((p).pte & (bits))
 #define pte_set_bits(p, bits) ((p).pte |= (bits))
 #define pte_clear_bits(p, bits) ((p).pte &= ~(bits))
 #define pte_copy(to, from) ((to).pte = (from).pte)
-#define pte_is_zero(p) (!((p).pte & ~_PAGE_NEWPAGE))
+#define pte_is_zero(p) (!((p).pte & ~_PAGE_NEEDSYNC))
 #define pte_set_val(p, phys, prot) (p).pte = (phys | pgprot_val(prot))
 
 typedef unsigned long phys_t;
 
-#endif
-
 typedef struct { unsigned long pgprot; } pgprot_t;
 
 typedef struct page *pgtable_t;

arch/um/include/asm/pgalloc.h

@@ -31,7 +31,7 @@ do {								\
 	tlb_remove_page_ptdesc((tlb), (page_ptdesc(pte)));	\
 } while (0)
 
-#ifdef CONFIG_3_LEVEL_PGTABLES
+#if CONFIG_PGTABLE_LEVELS > 2
 
 #define __pmd_free_tlb(tlb, pmd, address)			\
 do {								\
@@ -39,6 +39,15 @@ do {								\
 	tlb_remove_page_ptdesc((tlb), virt_to_ptdesc(pmd));	\
 } while (0)
 
+#if CONFIG_PGTABLE_LEVELS > 3
+
+#define __pud_free_tlb(tlb, pud, address)			\
+do {								\
+	pagetable_pud_dtor(virt_to_ptdesc(pud));		\
+	tlb_remove_page_ptdesc((tlb), virt_to_ptdesc(pud));	\
+} while (0)
+
+#endif
 #endif
 
 #endif

arch/um/include/asm/pgtable-2level.h

@@ -31,7 +31,7 @@
         printk("%s:%d: bad pgd %p(%08lx).\n", __FILE__, __LINE__, &(e), \
 	       pgd_val(e))
 
-static inline int pgd_newpage(pgd_t pgd)	{ return 0; }
+static inline int pgd_needsync(pgd_t pgd)	{ return 0; }
 static inline void pgd_mkuptodate(pgd_t pgd)	{ }
 
 #define set_pmd(pmdptr, pmdval) (*(pmdptr) = (pmdval))

arch/um/include/asm/pgtable-4level.h

@@ -4,21 +4,25 @@
  * Derived from include/asm-i386/pgtable.h
  */
 
-#ifndef __UM_PGTABLE_3LEVEL_H
-#define __UM_PGTABLE_3LEVEL_H
+#ifndef __UM_PGTABLE_4LEVEL_H
+#define __UM_PGTABLE_4LEVEL_H
 
-#include <asm-generic/pgtable-nopud.h>
+#include <asm-generic/pgtable-nop4d.h>
 
-/* PGDIR_SHIFT determines what a third-level page table entry can map */
+/* PGDIR_SHIFT determines what a fourth-level page table entry can map */
 
-#ifdef CONFIG_64BIT
-#define PGDIR_SHIFT	30
-#else
-#define PGDIR_SHIFT	31
-#endif
+#define PGDIR_SHIFT	39
 #define PGDIR_SIZE	(1UL << PGDIR_SHIFT)
 #define PGDIR_MASK	(~(PGDIR_SIZE-1))
 
+/* PUD_SHIFT determines the size of the area a third-level page table can
+ * map
+ */
+
+#define PUD_SHIFT	30
+#define PUD_SIZE	(1UL << PUD_SHIFT)
+#define PUD_MASK	(~(PUD_SIZE-1))
+
 /* PMD_SHIFT determines the size of the area a second-level page table can
  * map
  */
@@ -32,13 +36,9 @@
  */
 
 #define PTRS_PER_PTE 512
-#ifdef CONFIG_64BIT
 #define PTRS_PER_PMD 512
+#define PTRS_PER_PUD 512
 #define PTRS_PER_PGD 512
-#else
-#define PTRS_PER_PMD 1024
-#define PTRS_PER_PGD 1024
-#endif
 
 #define USER_PTRS_PER_PGD ((TASK_SIZE + (PGDIR_SIZE - 1)) / PGDIR_SIZE)
 
@@ -48,11 +48,14 @@
 #define pmd_ERROR(e) \
         printk("%s:%d: bad pmd %p(%016lx).\n", __FILE__, __LINE__, &(e), \
 	       pmd_val(e))
+#define pud_ERROR(e) \
+        printk("%s:%d: bad pud %p(%016lx).\n", __FILE__, __LINE__, &(e), \
+	       pud_val(e))
 #define pgd_ERROR(e) \
         printk("%s:%d: bad pgd %p(%016lx).\n", __FILE__, __LINE__, &(e), \
 	       pgd_val(e))
 
-#define pud_none(x)	(!(pud_val(x) & ~_PAGE_NEWPAGE))
+#define pud_none(x)	(!(pud_val(x) & ~_PAGE_NEEDSYNC))
 #define	pud_bad(x)	((pud_val(x) & (~PAGE_MASK & ~_PAGE_USER)) != _KERNPG_TABLE)
 #define pud_present(x)	(pud_val(x) & _PAGE_PRESENT)
 #define pud_populate(mm, pud, pmd) \
@@ -60,23 +63,40 @@
 
 #define set_pud(pudptr, pudval) (*(pudptr) = (pudval))
 
-static inline int pgd_newpage(pgd_t pgd)
+#define p4d_none(x)	(!(p4d_val(x) & ~_PAGE_NEEDSYNC))
+#define	p4d_bad(x)	((p4d_val(x) & (~PAGE_MASK & ~_PAGE_USER)) != _KERNPG_TABLE)
+#define p4d_present(x)	(p4d_val(x) & _PAGE_PRESENT)
+#define p4d_populate(mm, p4d, pud) \
+	set_p4d(p4d, __p4d(_PAGE_TABLE + __pa(pud)))
+
+#define set_p4d(p4dptr, p4dval) (*(p4dptr) = (p4dval))
+
+
+static inline int pgd_needsync(pgd_t pgd)
 {
-	return(pgd_val(pgd) & _PAGE_NEWPAGE);
+	return pgd_val(pgd) & _PAGE_NEEDSYNC;
 }
 
-static inline void pgd_mkuptodate(pgd_t pgd) { pgd_val(pgd) &= ~_PAGE_NEWPAGE; }
+static inline void pgd_mkuptodate(pgd_t pgd) { pgd_val(pgd) &= ~_PAGE_NEEDSYNC; }
 
 #define set_pmd(pmdptr, pmdval) (*(pmdptr) = (pmdval))
 
 static inline void pud_clear (pud_t *pud)
 {
-	set_pud(pud, __pud(_PAGE_NEWPAGE));
+	set_pud(pud, __pud(_PAGE_NEEDSYNC));
+}
+
+static inline void p4d_clear (p4d_t *p4d)
+{
+	set_p4d(p4d, __p4d(_PAGE_NEEDSYNC));
 }
 
 #define pud_page(pud) phys_to_page(pud_val(pud) & PAGE_MASK)
 #define pud_pgtable(pud) ((pmd_t *) __va(pud_val(pud) & PAGE_MASK))
 
+#define p4d_page(p4d) phys_to_page(p4d_val(p4d) & PAGE_MASK)
+#define p4d_pgtable(p4d) ((pud_t *) __va(p4d_val(p4d) & PAGE_MASK))
+
 static inline unsigned long pte_pfn(pte_t pte)
 {
 	return phys_to_pfn(pte_val(pte));
@@ -97,4 +117,3 @@ static inline pmd_t pfn_pmd(unsigned long page_nr, pgprot_t pgprot)
 }
 
 #endif
-

arch/um/include/asm/pgtable.h

@@ -11,8 +11,7 @@
 #include <asm/fixmap.h>
 
 #define _PAGE_PRESENT	0x001
-#define _PAGE_NEWPAGE	0x002
-#define _PAGE_NEWPROT	0x004
+#define _PAGE_NEEDSYNC	0x002
 #define _PAGE_RW	0x020
 #define _PAGE_USER	0x040
 #define _PAGE_ACCESSED	0x080
@@ -24,10 +23,12 @@
 /* We borrow bit 10 to store the exclusive marker in swap PTEs. */
 #define _PAGE_SWP_EXCLUSIVE	0x400
 
-#ifdef CONFIG_3_LEVEL_PGTABLES
-#include <asm/pgtable-3level.h>
-#else
+#if CONFIG_PGTABLE_LEVELS == 4
+#include <asm/pgtable-4level.h>
+#elif CONFIG_PGTABLE_LEVELS == 2
 #include <asm/pgtable-2level.h>
+#else
+#error "Unsupported number of page table levels"
 #endif
 
 extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
@@ -78,22 +79,22 @@ extern unsigned long end_iomem;
  */
 #define ZERO_PAGE(vaddr) virt_to_page(empty_zero_page)
 
-#define pte_clear(mm,addr,xp) pte_set_val(*(xp), (phys_t) 0, __pgprot(_PAGE_NEWPAGE))
+#define pte_clear(mm, addr, xp) pte_set_val(*(xp), (phys_t) 0, __pgprot(_PAGE_NEEDSYNC))
 
-#define pmd_none(x)	(!((unsigned long)pmd_val(x) & ~_PAGE_NEWPAGE))
+#define pmd_none(x)	(!((unsigned long)pmd_val(x) & ~_PAGE_NEEDSYNC))
 #define	pmd_bad(x)	((pmd_val(x) & (~PAGE_MASK & ~_PAGE_USER)) != _KERNPG_TABLE)
 
 #define pmd_present(x)	(pmd_val(x) & _PAGE_PRESENT)
-#define pmd_clear(xp)	do { pmd_val(*(xp)) = _PAGE_NEWPAGE; } while (0)
+#define pmd_clear(xp)	do { pmd_val(*(xp)) = _PAGE_NEEDSYNC; } while (0)
 
-#define pmd_newpage(x)  (pmd_val(x) & _PAGE_NEWPAGE)
-#define pmd_mkuptodate(x) (pmd_val(x) &= ~_PAGE_NEWPAGE)
+#define pmd_needsync(x)   (pmd_val(x) & _PAGE_NEEDSYNC)
+#define pmd_mkuptodate(x) (pmd_val(x) &= ~_PAGE_NEEDSYNC)
 
-#define pud_newpage(x)  (pud_val(x) & _PAGE_NEWPAGE)
-#define pud_mkuptodate(x) (pud_val(x) &= ~_PAGE_NEWPAGE)
+#define pud_needsync(x)   (pud_val(x) & _PAGE_NEEDSYNC)
+#define pud_mkuptodate(x) (pud_val(x) &= ~_PAGE_NEEDSYNC)
 
-#define p4d_newpage(x)  (p4d_val(x) & _PAGE_NEWPAGE)
-#define p4d_mkuptodate(x) (p4d_val(x) &= ~_PAGE_NEWPAGE)
+#define p4d_needsync(x)   (p4d_val(x) & _PAGE_NEEDSYNC)
+#define p4d_mkuptodate(x) (p4d_val(x) &= ~_PAGE_NEEDSYNC)
 
 #define pmd_pfn(pmd) (pmd_val(pmd) >> PAGE_SHIFT)
 #define pmd_page(pmd) phys_to_page(pmd_val(pmd) & PAGE_MASK)
@@ -144,14 +145,9 @@ static inline int pte_young(pte_t pte)
 	return pte_get_bits(pte, _PAGE_ACCESSED);
 }
 
-static inline int pte_newpage(pte_t pte)
+static inline int pte_needsync(pte_t pte)
 {
-	return pte_get_bits(pte, _PAGE_NEWPAGE);
-}
-
-static inline int pte_newprot(pte_t pte)
-{
-	return(pte_present(pte) && (pte_get_bits(pte, _PAGE_NEWPROT)));
+	return pte_get_bits(pte, _PAGE_NEEDSYNC);
 }
 
 /*
@@ -160,12 +156,6 @@ static inline int pte_newprot(pte_t pte)
  * =================================
  */
 
-static inline pte_t pte_mknewprot(pte_t pte)
-{
-	pte_set_bits(pte, _PAGE_NEWPROT);
-	return(pte);
-}
-
 static inline pte_t pte_mkclean(pte_t pte)
 {
 	pte_clear_bits(pte, _PAGE_DIRTY);
@@ -180,19 +170,14 @@ static inline pte_t pte_mkold(pte_t pte)
 
 static inline pte_t pte_wrprotect(pte_t pte)
 {
-	if (likely(pte_get_bits(pte, _PAGE_RW)))
-		pte_clear_bits(pte, _PAGE_RW);
-	else
-		return pte;
-	return(pte_mknewprot(pte));
+	pte_clear_bits(pte, _PAGE_RW);
+	return pte;
 }
 
 static inline pte_t pte_mkread(pte_t pte)
 {
-	if (unlikely(pte_get_bits(pte, _PAGE_USER)))
-		return pte;
 	pte_set_bits(pte, _PAGE_USER);
-	return(pte_mknewprot(pte));
+	return pte;
 }
 
 static inline pte_t pte_mkdirty(pte_t pte)
@@ -209,23 +194,19 @@ static inline pte_t pte_mkyoung(pte_t pte)
 
 static inline pte_t pte_mkwrite_novma(pte_t pte)
 {
-	if (unlikely(pte_get_bits(pte,  _PAGE_RW)))
-		return pte;
 	pte_set_bits(pte, _PAGE_RW);
-	return(pte_mknewprot(pte));
+	return pte;
 }
 
 static inline pte_t pte_mkuptodate(pte_t pte)
 {
-	pte_clear_bits(pte, _PAGE_NEWPAGE);
-	if(pte_present(pte))
-		pte_clear_bits(pte, _PAGE_NEWPROT);
-	return(pte);
+	pte_clear_bits(pte, _PAGE_NEEDSYNC);
+	return pte;
 }
 
-static inline pte_t pte_mknewpage(pte_t pte)
+static inline pte_t pte_mkneedsync(pte_t pte)
 {
-	pte_set_bits(pte, _PAGE_NEWPAGE);
+	pte_set_bits(pte, _PAGE_NEEDSYNC);
 	return(pte);
 }
 
@@ -233,13 +214,11 @@ static inline void set_pte(pte_t *pteptr, pte_t pteval)
 {
 	pte_copy(*pteptr, pteval);
 
-	/* If it's a swap entry, it needs to be marked _PAGE_NEWPAGE so
-	 * fix_range knows to unmap it.  _PAGE_NEWPROT is specific to
-	 * mapped pages.
+	/* If it's a swap entry, it needs to be marked _PAGE_NEEDSYNC so
+	 * update_pte_range knows to unmap it.
 	 */
 
-	*pteptr = pte_mknewpage(*pteptr);
-	if(pte_present(*pteptr)) *pteptr = pte_mknewprot(*pteptr);
+	*pteptr = pte_mkneedsync(*pteptr);
 }
 
 #define PFN_PTE_SHIFT		PAGE_SHIFT
@@ -279,7 +258,7 @@ static inline void set_ptes(struct mm_struct *mm, unsigned long addr,
 #define __HAVE_ARCH_PTE_SAME
 static inline int pte_same(pte_t pte_a, pte_t pte_b)
 {
-	return !((pte_val(pte_a) ^ pte_val(pte_b)) & ~_PAGE_NEWPAGE);
+	return !((pte_val(pte_a) ^ pte_val(pte_b)) & ~_PAGE_NEEDSYNC);
 }
 
 /*
@@ -294,8 +273,6 @@ static inline int pte_same(pte_t pte_a, pte_t pte_b)
 	({ pte_t pte;					\
 							\
 	pte_set_val(pte, page_to_phys(page), (pgprot));	\
-	if (pte_present(pte))				\
-		pte_mknewprot(pte_mknewpage(pte));	\
 	pte;})
 
 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
@@ -329,7 +306,7 @@ extern pte_t *virt_to_pte(struct mm_struct *mm, unsigned long addr);
  *   <--------------- offset ----------------> E < type -> 0 0 0 1 0
  *
  *   E is the exclusive marker that is not stored in swap entries.
- *   _PAGE_NEWPAGE (bit 1) is always set to 1 in set_pte().
+ *   _PAGE_NEEDSYNC (bit 1) is always set to 1 in set_pte().
  */
 #define __swp_type(x)			(((x).val >> 5) & 0x1f)
 #define __swp_offset(x)			((x).val >> 11)

arch/um/include/asm/processor-generic.h

@@ -20,10 +20,7 @@ struct task_struct;
 struct mm_struct;
 
 struct thread_struct {
-	struct pt_regs regs;
 	struct pt_regs *segv_regs;
-	void *fault_addr;
-	jmp_buf *fault_catcher;
 	struct task_struct *prev_sched;
 	struct arch_thread arch;
 	jmp_buf switch_buf;
@@ -33,12 +30,14 @@ struct thread_struct {
 			void *arg;
 		} thread;
 	} request;
+
+	/* Contains variable sized FP registers */
+	struct pt_regs regs;
 };
 
 #define INIT_THREAD \
 { \
 	.regs		   	= EMPTY_REGS,	\
-	.fault_addr		= NULL, \
 	.prev_sched		= NULL, \
 	.arch			= INIT_ARCH_THREAD, \
 	.request		= { } \

arch/um/include/asm/thread_info.h

@@ -17,35 +17,17 @@
 #include <sysdep/ptrace_user.h>
 
 struct thread_info {
-	struct task_struct	*task;		/* main task structure */
 	unsigned long		flags;		/* low level flags */
 	__u32			cpu;		/* current CPU */
 	int			preempt_count;  /* 0 => preemptable,
 						   <0 => BUG */
-	struct thread_info	*real_thread;    /* Points to non-IRQ stack */
-	unsigned long aux_fp_regs[FP_SIZE];	/* auxiliary fp_regs to save/restore
-						   them out-of-band */
 };
 
 #define INIT_THREAD_INFO(tsk)			\
 {						\
-	.task =		&tsk,			\
 	.flags =		0,		\
 	.cpu =		0,			\
 	.preempt_count = INIT_PREEMPT_COUNT,	\
-	.real_thread = NULL,			\
-}
-
-/* how to get the thread information struct from C */
-static inline struct thread_info *current_thread_info(void)
-{
-	struct thread_info *ti;
-	unsigned long mask = THREAD_SIZE - 1;
-	void *p;
-
-	asm volatile ("" : "=r" (p) : "0" (&ti));
-	ti = (struct thread_info *) (((unsigned long)p) & ~mask);
-	return ti;
 }
 
 #endif