13 files changed, 449 insertions, 454 deletions

diff --git a/arch/x86/um/Makefile b/arch/x86/um/Makefile
index 36e67fc97c22..b42c31cd2390 100644
--- a/arch/x86/um/Makefile
+++ b/arch/x86/um/Makefile
@@ -10,7 +10,7 @@ else
 endif
 
 obj-y = bugs_$(BITS).o delay.o fault.o \
-	ptrace_$(BITS).o ptrace_user.o setjmp_$(BITS).o signal.o \
+	ptrace.o ptrace_$(BITS).o ptrace_user.o setjmp_$(BITS).o signal.o \
 	stub_segv.o \
 	sys_call_table_$(BITS).o sysrq_$(BITS).o tls_$(BITS).o \
 	mem_$(BITS).o subarch.o os-Linux/
diff --git a/arch/x86/um/asm/elf.h b/arch/x86/um/asm/elf.h
index 6052200fe925..62ed5d68a978 100644
--- a/arch/x86/um/asm/elf.h
+++ b/arch/x86/um/asm/elf.h
@@ -8,6 +8,8 @@
 #include <asm/user.h>
 #include <skas.h>
 
+#define CORE_DUMP_USE_REGSET
+
 #ifdef CONFIG_X86_32
 
 #define R_386_NONE	0
diff --git a/arch/x86/um/asm/ptrace.h b/arch/x86/um/asm/ptrace.h
index 2fef3da55533..2641d28d115c 100644
--- a/arch/x86/um/asm/ptrace.h
+++ b/arch/x86/um/asm/ptrace.h
@@ -2,6 +2,16 @@
 #ifndef __UM_X86_PTRACE_H
 #define __UM_X86_PTRACE_H
 
+/* This is here because signal.c needs the REGSET_FP_LEGACY definition */
+enum {
+	REGSET_GENERAL,
+#ifdef CONFIG_X86_32
+	REGSET_FP_LEGACY,
+#endif
+	REGSET_FP,
+	REGSET_XSTATE,
+};
+
 #include <linux/compiler.h>
 #ifndef CONFIG_X86_32
 #define __FRAME_OFFSETS /* Needed to get the R* macros */
diff --git a/arch/x86/um/os-Linux/registers.c b/arch/x86/um/os-Linux/registers.c
index f8e5516d9708..76eaeb93928c 100644
--- a/arch/x86/um/os-Linux/registers.c
+++ b/arch/x86/um/os-Linux/registers.c
@@ -16,133 +16,58 @@
 #include <asm/sigcontext.h>
 #include <linux/elf.h>
 #include <registers.h>
+#include <sys/mman.h>
 
-static int have_xstate_support;
+unsigned long host_fp_size;
 
-static int save_i387_registers(int pid, unsigned long *fp_regs)
-{
-	if (ptrace(PTRACE_GETFPREGS, pid, 0, fp_regs) < 0)
-		return -errno;
-	return 0;
-}
-
-static int save_fp_registers(int pid, unsigned long *fp_regs)
+int get_fp_registers(int pid, unsigned long *regs)
 {
-#ifdef PTRACE_GETREGSET
-	struct iovec iov;
+	struct iovec iov = {
+		.iov_base = regs,
+		.iov_len = host_fp_size,
+	};
 
-	if (have_xstate_support) {
-		iov.iov_base = fp_regs;
-		iov.iov_len = FP_SIZE * sizeof(unsigned long);
-		if (ptrace(PTRACE_GETREGSET, pid, NT_X86_XSTATE, &iov) < 0)
-			return -errno;
-		return 0;
-	} else
-#endif
-		return save_i387_registers(pid, fp_regs);
-}
-
-static int restore_i387_registers(int pid, unsigned long *fp_regs)
-{
-	if (ptrace(PTRACE_SETFPREGS, pid, 0, fp_regs) < 0)
+	if (ptrace(PTRACE_GETREGSET, pid, NT_X86_XSTATE, &iov) < 0)
 		return -errno;
 	return 0;
 }
 
-static int restore_fp_registers(int pid, unsigned long *fp_regs)
-{
-#ifdef PTRACE_SETREGSET
-	struct iovec iov;
-	if (have_xstate_support) {
-		iov.iov_base = fp_regs;
-		iov.iov_len = FP_SIZE * sizeof(unsigned long);
-		if (ptrace(PTRACE_SETREGSET, pid, NT_X86_XSTATE, &iov) < 0)
-			return -errno;
-		return 0;
-	} else
-#endif
-		return restore_i387_registers(pid, fp_regs);
-}
-
-#ifdef __i386__
-int have_fpx_regs = 1;
-static int save_fpx_registers(int pid, unsigned long *fp_regs)
+int put_fp_registers(int pid, unsigned long *regs)
 {
-	if (ptrace(PTRACE_GETFPXREGS, pid, 0, fp_regs) < 0)
-		return -errno;
-	return 0;
-}
+	struct iovec iov = {
+		.iov_base = regs,
+		.iov_len = host_fp_size,
+	};
 
-static int restore_fpx_registers(int pid, unsigned long *fp_regs)
-{
-	if (ptrace(PTRACE_SETFPXREGS, pid, 0, fp_regs) < 0)
+	if (ptrace(PTRACE_SETREGSET, pid, NT_X86_XSTATE, &iov) < 0)
 		return -errno;
 	return 0;
 }
 
-int get_fp_registers(int pid, unsigned long *regs)
-{
-	if (have_fpx_regs)
-		return save_fpx_registers(pid, regs);
-	else
-		return save_fp_registers(pid, regs);
-}
-
-int put_fp_registers(int pid, unsigned long *regs)
-{
-	if (have_fpx_regs)
-		return restore_fpx_registers(pid, regs);
-	else
-		return restore_fp_registers(pid, regs);
-}
-
-void arch_init_registers(int pid)
-{
-	struct user_fpxregs_struct fpx_regs;
-	int err;
-
-	err = ptrace(PTRACE_GETFPXREGS, pid, 0, &fpx_regs);
-	if (!err)
-		return;
-
-	if (errno != EIO)
-		panic("check_ptrace : PTRACE_GETFPXREGS failed, errno = %d",
-		      errno);
-
-	have_fpx_regs = 0;
-}
-#else
-
-int get_fp_registers(int pid, unsigned long *regs)
+int arch_init_registers(int pid)
 {
-	return save_fp_registers(pid, regs);
+	struct iovec iov = {
+		/* Just use plenty of space, it does not cost us anything */
+		.iov_len = 2 * 1024 * 1024,
+	};
+	int ret;
+
+	iov.iov_base = mmap(NULL, iov.iov_len, PROT_WRITE | PROT_READ,
+			    MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
+	if (iov.iov_base == MAP_FAILED)
+		return -ENOMEM;
+
+	/* GDB has x86_xsave_length, which uses x86_cpuid_count */
+	ret = ptrace(PTRACE_GETREGSET, pid, NT_X86_XSTATE, &iov);
+	if (ret)
+		ret = -errno;
+	munmap(iov.iov_base, 2 * 1024 * 1024);
+
+	host_fp_size = iov.iov_len;
+
+	return ret;
 }
 
-int put_fp_registers(int pid, unsigned long *regs)
-{
-	return restore_fp_registers(pid, regs);
-}
-
-void arch_init_registers(int pid)
-{
-#ifdef PTRACE_GETREGSET
-	void * fp_regs;
-	struct iovec iov;
-
-	fp_regs = malloc(FP_SIZE * sizeof(unsigned long));
-	if(fp_regs == NULL)
-		return;
-
-	iov.iov_base = fp_regs;
-	iov.iov_len = FP_SIZE * sizeof(unsigned long);
-	if (ptrace(PTRACE_GETREGSET, pid, NT_X86_XSTATE, &iov) == 0)
-		have_xstate_support = 1;
-
-	free(fp_regs);
-#endif
-}
-#endif
-
 unsigned long get_thread_reg(int reg, jmp_buf *buf)
 {
 	switch (reg) {
diff --git a/arch/x86/um/ptrace.c b/arch/x86/um/ptrace.c
new file mode 100644
index 000000000000..54d924bc45ce
--- /dev/null
+++ b/arch/x86/um/ptrace.c
@@ -0,0 +1,267 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/sched.h>
+#include <linux/elf.h>
+#include <linux/regset.h>
+#include <asm/user32.h>
+#include <asm/sigcontext.h>
+
+#ifdef CONFIG_X86_32
+/*
+ * FPU tag word conversions.
+ */
+
+static inline unsigned short twd_i387_to_fxsr(unsigned short twd)
+{
+	unsigned int tmp; /* to avoid 16 bit prefixes in the code */
+
+	/* Transform each pair of bits into 01 (valid) or 00 (empty) */
+	tmp = ~twd;
+	tmp = (tmp | (tmp>>1)) & 0x5555; /* 0V0V0V0V0V0V0V0V */
+	/* and move the valid bits to the lower byte. */
+	tmp = (tmp | (tmp >> 1)) & 0x3333; /* 00VV00VV00VV00VV */
+	tmp = (tmp | (tmp >> 2)) & 0x0f0f; /* 0000VVVV0000VVVV */
+	tmp = (tmp | (tmp >> 4)) & 0x00ff; /* 00000000VVVVVVVV */
+	return tmp;
+}
+
+static inline unsigned long twd_fxsr_to_i387(struct user_fxsr_struct *fxsave)
+{
+	struct _fpxreg *st = NULL;
+	unsigned long twd = (unsigned long) fxsave->twd;
+	unsigned long tag;
+	unsigned long ret = 0xffff0000;
+	int i;
+
+#define FPREG_ADDR(f, n)	((char *)&(f)->st_space + (n) * 16)
+
+	for (i = 0; i < 8; i++) {
+		if (twd & 0x1) {
+			st = (struct _fpxreg *) FPREG_ADDR(fxsave, i);
+
+			switch (st->exponent & 0x7fff) {
+			case 0x7fff:
+				tag = 2;		/* Special */
+				break;
+			case 0x0000:
+				if (!st->significand[0] &&
+				    !st->significand[1] &&
+				    !st->significand[2] &&
+				    !st->significand[3]) {
+					tag = 1;	/* Zero */
+				} else {
+					tag = 2;	/* Special */
+				}
+				break;
+			default:
+				if (st->significand[3] & 0x8000)
+					tag = 0;	/* Valid */
+				else
+					tag = 2;	/* Special */
+				break;
+			}
+		} else {
+			tag = 3;			/* Empty */
+		}
+		ret |= (tag << (2 * i));
+		twd = twd >> 1;
+	}
+	return ret;
+}
+
+/* Get/set the old 32bit i387 registers (pre-FPX) */
+static int fpregs_legacy_get(struct task_struct *target,
+			     const struct user_regset *regset,
+			     struct membuf to)
+{
+	struct user_fxsr_struct *fxsave = (void *)target->thread.regs.regs.fp;
+	int i;
+
+	membuf_store(&to, (unsigned long)fxsave->cwd | 0xffff0000ul);
+	membuf_store(&to, (unsigned long)fxsave->swd | 0xffff0000ul);
+	membuf_store(&to, twd_fxsr_to_i387(fxsave));
+	membuf_store(&to, fxsave->fip);
+	membuf_store(&to, fxsave->fcs | ((unsigned long)fxsave->fop << 16));
+	membuf_store(&to, fxsave->foo);
+	membuf_store(&to, fxsave->fos);
+
+	for (i = 0; i < 8; i++)
+		membuf_write(&to, (void *)fxsave->st_space + i * 16, 10);
+
+	return 0;
+}
+
+static int fpregs_legacy_set(struct task_struct *target,
+			     const struct user_regset *regset,
+			     unsigned int pos, unsigned int count,
+			     const void *kbuf, const void __user *ubuf)
+{
+	struct user_fxsr_struct *fxsave = (void *)target->thread.regs.regs.fp;
+	const struct user_i387_struct *from;
+	struct user_i387_struct buf;
+	int i;
+
+	if (ubuf) {
+		if (copy_from_user(&buf, ubuf, sizeof(buf)))
+			return -EFAULT;
+		from = &buf;
+	} else {
+		from = kbuf;
+	}
+
+	fxsave->cwd = (unsigned short)(from->cwd & 0xffff);
+	fxsave->swd = (unsigned short)(from->swd & 0xffff);
+	fxsave->twd = twd_i387_to_fxsr((unsigned short)(from->twd & 0xffff));
+	fxsave->fip = from->fip;
+	fxsave->fop = (unsigned short)((from->fcs & 0xffff0000ul) >> 16);
+	fxsave->fcs = (from->fcs & 0xffff);
+	fxsave->foo = from->foo;
+	fxsave->fos = from->fos;
+
+	for (i = 0; i < 8; i++) {
+		memcpy((void *)fxsave->st_space + i * 16,
+		       (void *)from->st_space + i * 10, 10);
+	}
+
+	return 0;
+}
+#endif
+
+static int genregs_get(struct task_struct *target,
+		       const struct user_regset *regset,
+		       struct membuf to)
+{
+	int reg;
+
+	for (reg = 0; to.left; reg++)
+		membuf_store(&to, getreg(target, reg * sizeof(unsigned long)));
+	return 0;
+}
+
+static int genregs_set(struct task_struct *target,
+		       const struct user_regset *regset,
+		       unsigned int pos, unsigned int count,
+		       const void *kbuf, const void __user *ubuf)
+{
+	int ret = 0;
+
+	if (kbuf) {
+		const unsigned long *k = kbuf;
+
+		while (count >= sizeof(*k) && !ret) {
+			ret = putreg(target, pos, *k++);
+			count -= sizeof(*k);
+			pos += sizeof(*k);
+		}
+	} else {
+		const unsigned long  __user *u = ubuf;
+
+		while (count >= sizeof(*u) && !ret) {
+			unsigned long word;
+
+			ret = __get_user(word, u++);
+			if (ret)
+				break;
+			ret = putreg(target, pos, word);
+			count -= sizeof(*u);
+			pos += sizeof(*u);
+		}
+	}
+	return ret;
+}
+
+static int generic_fpregs_active(struct task_struct *target, const struct user_regset *regset)
+{
+	return regset->n;
+}
+
+static int generic_fpregs_get(struct task_struct *target,
+			      const struct user_regset *regset,
+			      struct membuf to)
+{
+	void *fpregs = task_pt_regs(target)->regs.fp;
+
+	membuf_write(&to, fpregs, regset->size * regset->n);
+	return 0;
+}
+
+static int generic_fpregs_set(struct task_struct *target,
+			      const struct user_regset *regset,
+			      unsigned int pos, unsigned int count,
+			      const void *kbuf, const void __user *ubuf)
+{
+	void *fpregs = task_pt_regs(target)->regs.fp;
+
+	return user_regset_copyin(&pos, &count, &kbuf, &ubuf,
+				  fpregs, 0, regset->size * regset->n);
+}
+
+static struct user_regset uml_regsets[] __ro_after_init = {
+	[REGSET_GENERAL] = {
+		.core_note_type	= NT_PRSTATUS,
+		.n		= sizeof(struct user_regs_struct) / sizeof(long),
+		.size		= sizeof(long),
+		.align		= sizeof(long),
+		.regset_get	= genregs_get,
+		.set		= genregs_set
+	},
+#ifdef CONFIG_X86_32
+	/* Old FP registers, they are needed in signal frames */
+	[REGSET_FP_LEGACY] = {
+		.core_note_type	= NT_PRFPREG,
+		.n		= sizeof(struct user_i387_ia32_struct) / sizeof(long),
+		.size		= sizeof(long),
+		.align		= sizeof(long),
+		.active		= generic_fpregs_active,
+		.regset_get	= fpregs_legacy_get,
+		.set		= fpregs_legacy_set,
+	},
+#endif
+	[REGSET_FP] = {
+#ifdef CONFIG_X86_32
+		.core_note_type	= NT_PRXFPREG,
+		.n		= sizeof(struct user32_fxsr_struct) / sizeof(long),
+#else
+		.core_note_type	= NT_PRFPREG,
+		.n		= sizeof(struct user_i387_struct) / sizeof(long),
+#endif
+		.size		= sizeof(long),
+		.align		= sizeof(long),
+		.active		= generic_fpregs_active,
+		.regset_get	= generic_fpregs_get,
+		.set		= generic_fpregs_set,
+	},
+	[REGSET_XSTATE] = {
+		.core_note_type	= NT_X86_XSTATE,
+		.size		= sizeof(long),
+		.align		= sizeof(long),
+		.active		= generic_fpregs_active,
+		.regset_get	= generic_fpregs_get,
+		.set		= generic_fpregs_set,
+	},
+	/* TODO: Add TLS regset for 32bit */
+};
+
+const struct user_regset_view user_uml_view = {
+#ifdef CONFIG_X86_32
+	.name = "i386", .e_machine = EM_386,
+#else
+	.name = "x86_64", .e_machine = EM_X86_64,
+#endif
+	.regsets = uml_regsets, .n = ARRAY_SIZE(uml_regsets)
+};
+
+const struct user_regset_view *
+task_user_regset_view(struct task_struct *tsk)
+{
+	return &user_uml_view;
+}
+
+static int __init init_regset_xstate_info(void)
+{
+	uml_regsets[REGSET_XSTATE].n =
+		host_fp_size / uml_regsets[REGSET_XSTATE].size;
+
+	return 0;
+}
+arch_initcall(init_regset_xstate_info);
diff --git a/arch/x86/um/ptrace_32.c b/arch/x86/um/ptrace_32.c
index b8b85a52eb6f..3af3cb821524 100644
--- a/arch/x86/um/ptrace_32.c
+++ b/arch/x86/um/ptrace_32.c
@@ -6,6 +6,7 @@
 #include <linux/mm.h>
 #include <linux/sched.h>
 #include <linux/uaccess.h>
+#include <linux/regset.h>
 #include <asm/ptrace-abi.h>
 #include <registers.h>
 #include <skas.h>
@@ -168,69 +169,6 @@ int peek_user(struct task_struct *child, long addr, long data)
 	return put_user(tmp, (unsigned long __user *) data);
 }
 
-/* FIXME: Do the required conversions instead of erroring out */
-extern int have_fpx_regs;
-
-static int get_fpregs(struct user_i387_struct __user *buf, struct task_struct *child)
-{
-	int n;
-
-	if (have_fpx_regs)
-		return -EINVAL;
-
-	n = copy_to_user(buf, &child->thread.regs.regs.fp,
-			 sizeof(struct user_i387_struct));
-	if(n > 0)
-		return -EFAULT;
-
-	return n;
-}
-
-static int set_fpregs(struct user_i387_struct __user *buf, struct task_struct *child)
-{
-	int n;
-
-	if (have_fpx_regs)
-		return -EINVAL;
-
-	n = copy_from_user(&child->thread.regs.regs.fp, buf,
-			   sizeof(struct user_i387_struct));
-	if (n > 0)
-		return -EFAULT;
-
-	return 0;
-}
-
-static int get_fpxregs(struct user_fxsr_struct __user *buf, struct task_struct *child)
-{
-	int n;
-
-	if (!have_fpx_regs)
-		return -EINVAL;
-
-	n = copy_to_user(buf, &child->thread.regs.regs.fp,
-			 sizeof(struct user_fxsr_struct));
-	if(n > 0)
-		return -EFAULT;
-
-	return n;
-}
-
-static int set_fpxregs(struct user_fxsr_struct __user *buf, struct task_struct *child)
-{
-	int n;
-
-	if (!have_fpx_regs)
-		return -EINVAL;
-
-	n = copy_from_user(&child->thread.regs.regs.fp, buf,
-			   sizeof(struct user_fxsr_struct));
-	if (n > 0)
-		return -EFAULT;
-
-	return 0;
-}
-
 long subarch_ptrace(struct task_struct *child, long request,
 		    unsigned long addr, unsigned long data)
 {
@@ -238,17 +176,25 @@ long subarch_ptrace(struct task_struct *child, long request,
 	void __user *datap = (void __user *) data;
 	switch (request) {
 	case PTRACE_GETFPREGS: /* Get the child FPU state. */
-		ret = get_fpregs(datap, child);
-		break;
+		return copy_regset_to_user(child, task_user_regset_view(child),
+					   REGSET_FP_LEGACY,
+					   0, sizeof(struct user_i387_struct),
+					   datap);
 	case PTRACE_SETFPREGS: /* Set the child FPU state. */
-		ret = set_fpregs(datap, child);
-		break;
+		return copy_regset_from_user(child, task_user_regset_view(child),
+					     REGSET_FP_LEGACY,
+					     0, sizeof(struct user_i387_struct),
+					     datap);
 	case PTRACE_GETFPXREGS: /* Get the child FPU state. */
-		ret = get_fpxregs(datap, child);
-		break;
+		return copy_regset_to_user(child, task_user_regset_view(child),
+					   REGSET_FP,
+					   0, sizeof(struct user_fxsr_struct),
+					   datap);
 	case PTRACE_SETFPXREGS: /* Set the child FPU state. */
-		ret = set_fpxregs(datap, child);
-		break;
+		return copy_regset_from_user(child, task_user_regset_view(child),
+					     REGSET_FP,
+					     0, sizeof(struct user_fxsr_struct),
+					     datap);
 	default:
 		ret = -EIO;
 	}
diff --git a/arch/x86/um/ptrace_64.c b/arch/x86/um/ptrace_64.c
index f8bbad29cd0b..e0d4120a45c8 100644
--- a/arch/x86/um/ptrace_64.c
+++ b/arch/x86/um/ptrace_64.c
@@ -8,6 +8,7 @@
 #include <linux/mm.h>
 #include <linux/sched.h>
 #include <linux/errno.h>
+#include <linux/regset.h>
 #define __FRAME_OFFSETS
 #include <asm/ptrace.h>
 #include <linux/uaccess.h>
@@ -188,30 +189,6 @@ int peek_user(struct task_struct *child, long addr, long data)
 	return put_user(tmp, (unsigned long *) data);
 }
 
-static int get_fpregs(struct user_i387_struct __user *buf, struct task_struct *child)
-{
-	int n;
-
-	n = copy_to_user(buf, &child->thread.regs.regs.fp,
-			 sizeof(struct user_i387_struct));
-	if (n > 0)
-		return -EFAULT;
-
-	return n;
-}
-
-static int set_fpregs(struct user_i387_struct __user *buf, struct task_struct *child)
-{
-	int n;
-
-	n = copy_from_user(&child->thread.regs.regs.fp, buf,
-			   sizeof(struct user_i387_struct));
-	if (n > 0)
-		return -EFAULT;
-
-	return 0;
-}
-
 long subarch_ptrace(struct task_struct *child, long request,
 		    unsigned long addr, unsigned long data)
 {
@@ -220,11 +197,15 @@ long subarch_ptrace(struct task_struct *child, long request,
 
 	switch (request) {
 	case PTRACE_GETFPREGS: /* Get the child FPU state. */
-		ret = get_fpregs(datap, child);
-		break;
+		return copy_regset_to_user(child, task_user_regset_view(child),
+					   REGSET_FP,
+					   0, sizeof(struct user_i387_struct),
+					   datap);
 	case PTRACE_SETFPREGS: /* Set the child FPU state. */
-		ret = set_fpregs(datap, child);
-		break;
+		return copy_regset_from_user(child, task_user_regset_view(child),
+					     REGSET_FP,
+					     0, sizeof(struct user_i387_struct),
+					     datap);
 	case PTRACE_ARCH_PRCTL:
 		/* XXX Calls ptrace on the host - needs some SMP thinking */
 		ret = arch_prctl(child, data, (void __user *) addr);
diff --git a/arch/x86/um/shared/sysdep/ptrace.h b/arch/x86/um/shared/sysdep/ptrace.h
index 6ca4ecabc55b..2dd4ca6713f8 100644
--- a/arch/x86/um/shared/sysdep/ptrace.h
+++ b/arch/x86/um/shared/sysdep/ptrace.h
@@ -56,12 +56,16 @@ struct syscall_args {
 				     UPT_SYSCALL_ARG5(r),	 \
 				     UPT_SYSCALL_ARG6(r) } } )
 
+extern unsigned long host_fp_size;
+
 struct uml_pt_regs {
 	unsigned long gp[MAX_REG_NR];
-	unsigned long fp[MAX_FP_NR];
 	struct faultinfo faultinfo;
 	long syscall;
 	int is_user;
+
+	/* Dynamically sized FP registers (holds an XSTATE) */
+	unsigned long fp[];
 };
 
 #define EMPTY_UML_PT_REGS { }
@@ -72,4 +76,6 @@ struct uml_pt_regs {
 
 extern int user_context(unsigned long sp);
 
+extern int arch_init_registers(int pid);
+
 #endif /* __SYSDEP_X86_PTRACE_H */
diff --git a/arch/x86/um/shared/sysdep/ptrace_32.h b/arch/x86/um/shared/sysdep/ptrace_32.h
index 0c4989842fbe..2392470cac4d 100644
--- a/arch/x86/um/shared/sysdep/ptrace_32.h
+++ b/arch/x86/um/shared/sysdep/ptrace_32.h
@@ -6,8 +6,6 @@
 #ifndef __SYSDEP_I386_PTRACE_H
 #define __SYSDEP_I386_PTRACE_H
 
-#define MAX_FP_NR HOST_FPX_SIZE
-
 #define UPT_SYSCALL_ARG1(r) UPT_BX(r)
 #define UPT_SYSCALL_ARG2(r) UPT_CX(r)
 #define UPT_SYSCALL_ARG3(r) UPT_DX(r)
@@ -15,6 +13,4 @@
 #define UPT_SYSCALL_ARG5(r) UPT_DI(r)
 #define UPT_SYSCALL_ARG6(r) UPT_BP(r)
 
-extern void arch_init_registers(int pid);
-
 #endif
diff --git a/arch/x86/um/shared/sysdep/ptrace_64.h b/arch/x86/um/shared/sysdep/ptrace_64.h
index 0dc223aa1c2d..e73573ac871f 100644
--- a/arch/x86/um/shared/sysdep/ptrace_64.h
+++ b/arch/x86/um/shared/sysdep/ptrace_64.h
@@ -8,8 +8,6 @@
 #ifndef __SYSDEP_X86_64_PTRACE_H
 #define __SYSDEP_X86_64_PTRACE_H
 
-#define MAX_FP_NR HOST_FP_SIZE
-
 #define REGS_R8(r) ((r)[HOST_R8])
 #define REGS_R9(r) ((r)[HOST_R9])
 #define REGS_R10(r) ((r)[HOST_R10])
@@ -57,6 +55,4 @@
 #define UPT_SYSCALL_ARG5(r) UPT_R8(r)
 #define UPT_SYSCALL_ARG6(r) UPT_R9(r)
 
-extern void arch_init_registers(int pid);
-
 #endif
diff --git a/arch/x86/um/shared/sysdep/ptrace_user.h b/arch/x86/um/shared/sysdep/ptrace_user.h
index 1d1a824fa652..98da23120538 100644
--- a/arch/x86/um/shared/sysdep/ptrace_user.h
+++ b/arch/x86/um/shared/sysdep/ptrace_user.h
@@ -11,12 +11,6 @@
 #define REGS_IP_INDEX HOST_IP
 #define REGS_SP_INDEX HOST_SP
 
-#ifdef __i386__
-#define FP_SIZE ((HOST_FPX_SIZE > HOST_FP_SIZE) ? HOST_FPX_SIZE : HOST_FP_SIZE)
-#else
-#define FP_SIZE HOST_FP_SIZE
-#endif
-
 /*
  * glibc before 2.27 does not include PTRACE_SYSEMU_SINGLESTEP in its enum,
  * ensure we have a definition by (re-)defining it here.
diff --git a/arch/x86/um/signal.c b/arch/x86/um/signal.c
index fa78c74e00cb..94b2b2bbae31 100644
--- a/arch/x86/um/signal.c
+++ b/arch/x86/um/signal.c
@@ -16,145 +16,24 @@
 #include <registers.h>
 #include <skas.h>
 
-#ifdef CONFIG_X86_32
-
-/*
- * FPU tag word conversions.
- */
-
-static inline unsigned short twd_i387_to_fxsr(unsigned short twd)
-{
-	unsigned int tmp; /* to avoid 16 bit prefixes in the code */
-
-	/* Transform each pair of bits into 01 (valid) or 00 (empty) */
-	tmp = ~twd;
-	tmp = (tmp | (tmp>>1)) & 0x5555; /* 0V0V0V0V0V0V0V0V */
-	/* and move the valid bits to the lower byte. */
-	tmp = (tmp | (tmp >> 1)) & 0x3333; /* 00VV00VV00VV00VV */
-	tmp = (tmp | (tmp >> 2)) & 0x0f0f; /* 0000VVVV0000VVVV */
-	tmp = (tmp | (tmp >> 4)) & 0x00ff; /* 00000000VVVVVVVV */
-	return tmp;
-}
-
-static inline unsigned long twd_fxsr_to_i387(struct user_fxsr_struct *fxsave)
-{
-	struct _fpxreg *st = NULL;
-	unsigned long twd = (unsigned long) fxsave->twd;
-	unsigned long tag;
-	unsigned long ret = 0xffff0000;
-	int i;
-
-#define FPREG_ADDR(f, n)	((char *)&(f)->st_space + (n) * 16)
-
-	for (i = 0; i < 8; i++) {
-		if (twd & 0x1) {
-			st = (struct _fpxreg *) FPREG_ADDR(fxsave, i);
-
-			switch (st->exponent & 0x7fff) {
-			case 0x7fff:
-				tag = 2;		/* Special */
-				break;
-			case 0x0000:
-				if ( !st->significand[0] &&
-				     !st->significand[1] &&
-				     !st->significand[2] &&
-				     !st->significand[3] ) {
-					tag = 1;	/* Zero */
-				} else {
-					tag = 2;	/* Special */
-				}
-				break;
-			default:
-				if (st->significand[3] & 0x8000) {
-					tag = 0;	/* Valid */
-				} else {
-					tag = 2;	/* Special */
-				}
-				break;
-			}
-		} else {
-			tag = 3;			/* Empty */
-		}
-		ret |= (tag << (2 * i));
-		twd = twd >> 1;
-	}
-	return ret;
-}
-
-static int convert_fxsr_to_user(struct _fpstate __user *buf,
-				struct user_fxsr_struct *fxsave)
-{
-	unsigned long env[7];
-	struct _fpreg __user *to;
-	struct _fpxreg *from;
-	int i;
-
-	env[0] = (unsigned long)fxsave->cwd | 0xffff0000ul;
-	env[1] = (unsigned long)fxsave->swd | 0xffff0000ul;
-	env[2] = twd_fxsr_to_i387(fxsave);
-	env[3] = fxsave->fip;
-	env[4] = fxsave->fcs | ((unsigned long)fxsave->fop << 16);
-	env[5] = fxsave->foo;
-	env[6] = fxsave->fos;
-
-	if (__copy_to_user(buf, env, 7 * sizeof(unsigned long)))
-		return 1;
-
-	to = &buf->_st[0];
-	from = (struct _fpxreg *) &fxsave->st_space[0];
-	for (i = 0; i < 8; i++, to++, from++) {
-		unsigned long __user *t = (unsigned long __user *)to;
-		unsigned long *f = (unsigned long *)from;
-
-		if (__put_user(*f, t) ||
-				__put_user(*(f + 1), t + 1) ||
-				__put_user(from->exponent, &to->exponent))
-			return 1;
-	}
-	return 0;
-}
-
-static int convert_fxsr_from_user(struct user_fxsr_struct *fxsave,
-				  struct _fpstate __user *buf)
-{
-	unsigned long env[7];
-	struct _fpxreg *to;
-	struct _fpreg __user *from;
-	int i;
-
-	if (copy_from_user( env, buf, 7 * sizeof(long)))
-		return 1;
-
-	fxsave->cwd = (unsigned short)(env[0] & 0xffff);
-	fxsave->swd = (unsigned short)(env[1] & 0xffff);
-	fxsave->twd = twd_i387_to_fxsr((unsigned short)(env[2] & 0xffff));
-	fxsave->fip = env[3];
-	fxsave->fop = (unsigned short)((env[4] & 0xffff0000ul) >> 16);
-	fxsave->fcs = (env[4] & 0xffff);
-	fxsave->foo = env[5];
-	fxsave->fos = env[6];
-
-	to = (struct _fpxreg *) &fxsave->st_space[0];
-	from = &buf->_st[0];
-	for (i = 0; i < 8; i++, to++, from++) {
-		unsigned long *t = (unsigned long *)to;
-		unsigned long __user *f = (unsigned long __user *)from;
-
-		if (__get_user(*t, f) ||
-		    __get_user(*(t + 1), f + 1) ||
-		    __get_user(to->exponent, &from->exponent))
-			return 1;
-	}
-	return 0;
-}
-
-extern int have_fpx_regs;
+#include <linux/regset.h>
+#include <asm/sigframe.h>
 
+#ifdef CONFIG_X86_32
+struct _xstate_64 {
+	struct _fpstate_64		fpstate;
+	struct _header			xstate_hdr;
+	struct _ymmh_state		ymmh;
+	/* New processor state extensions go here: */
+};
+#else
+#define _xstate_64 _xstate
 #endif
 
 static int copy_sc_from_user(struct pt_regs *regs,
 			     struct sigcontext __user *from)
 {
+	struct _xstate_64 __user *from_fp64;
 	struct sigcontext sc;
 	int err;
 
@@ -203,31 +82,26 @@ static int copy_sc_from_user(struct pt_regs *regs,
 #undef GETREG
 
 #ifdef CONFIG_X86_32
-	if (have_fpx_regs) {
-		struct user_fxsr_struct *fpx;
-		fpx = (void *)&regs->regs.fp;
-
-		err = convert_fxsr_from_user(fpx, (void *)sc.fpstate);
-		if (err)
-			return 1;
-	} else {
-		BUILD_BUG_ON(sizeof(regs->regs.fp) > sizeof(struct _fpstate));
-		err = copy_from_user(regs->regs.fp, (void *)sc.fpstate,
-				     sizeof(regs->regs.fp));
-		if (err)
-			return 1;
-	}
+	from_fp64 = ((void *)sc.fpstate) + offsetof(struct _fpstate_32, _fxsr_env);
 #else
-	{
-		/* FIXME: Save/restore extended state (past the 16 YMM regs) */
-		BUILD_BUG_ON(sizeof(regs->regs.fp) < sizeof(struct _xstate));
+	from_fp64 = (void *)sc.fpstate;
+#endif
 
-		err = copy_from_user(regs->regs.fp, (void *)sc.fpstate,
-				     sizeof(struct _xstate));
-		if (err)
-			return 1;
-	}
+	err = copy_from_user(regs->regs.fp, from_fp64, host_fp_size);
+	if (err)
+		return 1;
+
+#ifdef CONFIG_X86_32
+	/* Data is duplicated and this copy is the important one */
+	err = copy_regset_from_user(current,
+				    task_user_regset_view(current),
+				    REGSET_FP_LEGACY, 0,
+				    sizeof(struct user_i387_struct),
+				    (void *)sc.fpstate);
+	if (err < 0)
+		return err;
 #endif
+
 	return 0;
 }
 
@@ -235,6 +109,7 @@ static int copy_sc_to_user(struct sigcontext __user *to,
 			   struct _xstate __user *to_fp, struct pt_regs *regs,
 			   unsigned long mask)
 {
+	struct _xstate_64 __user *to_fp64;
 	struct sigcontext sc;
 	struct faultinfo * fi = &current->thread.arch.faultinfo;
 	int err;
@@ -286,36 +161,44 @@ static int copy_sc_to_user(struct sigcontext __user *to,
 		return 1;
 
 #ifdef CONFIG_X86_32
-	if (have_fpx_regs) {
-		struct user_fxsr_struct *fpx;
-
-		fpx = (void *)&regs->regs.fp;
+	err = copy_regset_to_user(current,
+				  task_user_regset_view(current),
+				  REGSET_FP_LEGACY, 0,
+				  sizeof(struct _fpstate_32), to_fp);
+	if (err < 0)
+		return err;
 
-		err = convert_fxsr_to_user(&to_fp->fpstate, fpx);
-		if (err)
-			return 1;
+	__put_user(X86_FXSR_MAGIC, &to_fp->fpstate.magic);
 
-		err |= __put_user(fpx->swd, &to_fp->fpstate.status);
-		err |= __put_user(X86_FXSR_MAGIC, &to_fp->fpstate.magic);
-		if (err)
-			return 1;
-
-	} else {
-		if (copy_to_user(to_fp, regs->regs.fp, sizeof(regs->regs.fp)))
-			return 1;
-
-		/* Need to fill in the sw_reserved bits ... */
-		BUILD_BUG_ON(offsetof(typeof(*to_fp),
-				      fpstate.sw_reserved.magic1) >=
-			     sizeof(struct _fpstate));
-		__put_user(0, &to_fp->fpstate.sw_reserved.magic1);
-		__put_user(sizeof(struct _fpstate),
-			   &to_fp->fpstate.sw_reserved.extended_size);
-	}
+	BUILD_BUG_ON(offsetof(struct _xstate, xstate_hdr) !=
+		     offsetof(struct _xstate_64, xstate_hdr) +
+			offsetof(struct _fpstate_32, _fxsr_env));
+	to_fp64 = (void *)to_fp + offsetof(struct _fpstate_32, _fxsr_env);
 #else
-	if (copy_to_user(to_fp, regs->regs.fp, sizeof(struct _xstate)))
+	to_fp64 = to_fp;
+#endif /* CONFIG_X86_32 */
+
+	if (copy_to_user(to_fp64, regs->regs.fp, host_fp_size))
 		return 1;
+
+	/*
+	 * Put magic/size values for userspace. We do not bother to verify them
+	 * later on, however, userspace needs them should it try to read the
+	 * XSTATE data. And ptrace does not fill in these parts.
+	 */
+	BUILD_BUG_ON(sizeof(int) != FP_XSTATE_MAGIC2_SIZE);
+#ifdef CONFIG_X86_32
+	__put_user(offsetof(struct _fpstate_32, _fxsr_env) +
+		   host_fp_size + FP_XSTATE_MAGIC2_SIZE,
+		   &to_fp64->fpstate.sw_reserved.extended_size);
+#else
+	__put_user(host_fp_size + FP_XSTATE_MAGIC2_SIZE,
+		   &to_fp64->fpstate.sw_reserved.extended_size);
 #endif
+	__put_user(host_fp_size, &to_fp64->fpstate.sw_reserved.xstate_size);
+
+	__put_user(FP_XSTATE_MAGIC1, &to_fp64->fpstate.sw_reserved.magic1);
+	__put_user(FP_XSTATE_MAGIC2, (int *)((void *)to_fp64 + host_fp_size));
 
 	return 0;
 }
@@ -333,34 +216,15 @@ static int copy_ucontext_to_user(struct ucontext __user *uc,
 	return err;
 }
 
-struct sigframe
-{
-	char __user *pretcode;
-	int sig;
-	struct sigcontext sc;
-	struct _xstate fpstate;
-	unsigned long extramask[_NSIG_WORDS-1];
-	char retcode[8];
-};
-
-struct rt_sigframe
-{
-	char __user *pretcode;
-	int sig;
-	struct siginfo __user *pinfo;
-	void __user *puc;
-	struct siginfo info;
-	struct ucontext uc;
-	struct _xstate fpstate;
-	char retcode[8];
-};
-
 int setup_signal_stack_sc(unsigned long stack_top, struct ksignal *ksig,
 			  struct pt_regs *regs, sigset_t *mask)
 {
+	size_t math_size = offsetof(struct _fpstate_32, _fxsr_env) +
+			   host_fp_size + FP_XSTATE_MAGIC2_SIZE;
 	struct sigframe __user *frame;
 	void __user *restorer;
 	int err = 0, sig = ksig->sig;
+	unsigned long fp_to;
 
 	/* This is the same calculation as i386 - ((sp + 4) & 15) == 0 */
 	stack_top = ((stack_top + 4) & -16UL) - 4;
@@ -368,13 +232,21 @@ int setup_signal_stack_sc(unsigned long stack_top, struct ksignal *ksig,
 	if (!access_ok(frame, sizeof(*frame)))
 		return 1;
 
+	/* Add required space for math frame */
+	frame = (struct sigframe __user *)((unsigned long)frame - math_size);
+
 	restorer = frame->retcode;
 	if (ksig->ka.sa.sa_flags & SA_RESTORER)
 		restorer = ksig->ka.sa.sa_restorer;
 
-	err |= __put_user(restorer, &frame->pretcode);
+	err |= __put_user(restorer, (void **)&frame->pretcode);
 	err |= __put_user(sig, &frame->sig);
-	err |= copy_sc_to_user(&frame->sc, &frame->fpstate, regs, mask->sig[0]);
+
+	fp_to = (unsigned long)frame + sizeof(*frame);
+
+	err |= copy_sc_to_user(&frame->sc,
+			       (struct _xstate __user *)fp_to,
+			       regs, mask->sig[0]);
 	if (_NSIG_WORDS > 1)
 		err |= __copy_to_user(&frame->extramask, &mask->sig[1],
 				      sizeof(frame->extramask));
@@ -404,26 +276,35 @@ int setup_signal_stack_sc(unsigned long stack_top, struct ksignal *ksig,
 int setup_signal_stack_si(unsigned long stack_top, struct ksignal *ksig,
 			  struct pt_regs *regs, sigset_t *mask)
 {
+	size_t math_size = offsetof(struct _fpstate_32, _fxsr_env) +
+			   host_fp_size + FP_XSTATE_MAGIC2_SIZE;
 	struct rt_sigframe __user *frame;
 	void __user *restorer;
 	int err = 0, sig = ksig->sig;
+	unsigned long fp_to;
 
 	stack_top &= -8UL;
 	frame = (struct rt_sigframe __user *) stack_top - 1;
 	if (!access_ok(frame, sizeof(*frame)))
 		return 1;
 
+	/* Add required space for math frame */
+	frame = (struct rt_sigframe __user *)((unsigned long)frame - math_size);
+
 	restorer = frame->retcode;
 	if (ksig->ka.sa.sa_flags & SA_RESTORER)
 		restorer = ksig->ka.sa.sa_restorer;
 
-	err |= __put_user(restorer, &frame->pretcode);
+	err |= __put_user(restorer, (void **)&frame->pretcode);
 	err |= __put_user(sig, &frame->sig);
-	err |= __put_user(&frame->info, &frame->pinfo);
-	err |= __put_user(&frame->uc, &frame->puc);
+	err |= __put_user(&frame->info, (void **)&frame->pinfo);
+	err |= __put_user(&frame->uc, (void **)&frame->puc);
 	err |= copy_siginfo_to_user(&frame->info, &ksig->info);
-	err |= copy_ucontext_to_user(&frame->uc, &frame->fpstate, mask,
-					PT_REGS_SP(regs));
+
+	fp_to = (unsigned long)frame + sizeof(*frame);
+
+	err |= copy_ucontext_to_user(&frame->uc, (struct _xstate __user *)fp_to,
+				     mask, PT_REGS_SP(regs));
 
 	/*
 	 * This is movl $,%eax ; int $0x80
@@ -475,27 +356,24 @@ SYSCALL_DEFINE0(sigreturn)
 
 #else
 
-struct rt_sigframe
-{
-	char __user *pretcode;
-	struct ucontext uc;
-	struct siginfo info;
-	struct _xstate fpstate;
-};
-
 int setup_signal_stack_si(unsigned long stack_top, struct ksignal *ksig,
 			  struct pt_regs *regs, sigset_t *set)
 {
+	unsigned long math_size = host_fp_size + FP_XSTATE_MAGIC2_SIZE;
 	struct rt_sigframe __user *frame;
 	int err = 0, sig = ksig->sig;
 	unsigned long fp_to;
 
 	frame = (struct rt_sigframe __user *)
 		round_down(stack_top - sizeof(struct rt_sigframe), 16);
+
+	/* Add required space for math frame */
+	frame = (struct rt_sigframe __user *)((unsigned long)frame - math_size);
+
 	/* Subtract 128 for a red zone and 8 for proper alignment */
 	frame = (struct rt_sigframe __user *) ((unsigned long) frame - 128 - 8);
 
-	if (!access_ok(frame, sizeof(*frame)))
+	if (!access_ok(frame, sizeof(*frame) + math_size))
 		goto out;
 
 	if (ksig->ka.sa.sa_flags & SA_SIGINFO) {
@@ -508,10 +386,12 @@ int setup_signal_stack_si(unsigned long stack_top, struct ksignal *ksig,
 	err |= __put_user(0, &frame->uc.uc_flags);
 	err |= __put_user(0, &frame->uc.uc_link);
 	err |= __save_altstack(&frame->uc.uc_stack, PT_REGS_SP(regs));
-	err |= copy_sc_to_user(&frame->uc.uc_mcontext, &frame->fpstate, regs,
-			       set->sig[0]);
 
-	fp_to = (unsigned long)&frame->fpstate;
+	fp_to = (unsigned long)frame + sizeof(*frame);
+
+	err |= copy_sc_to_user(&frame->uc.uc_mcontext,
+			       (struct _xstate __user *)fp_to,
+			       regs, set->sig[0]);
 
 	err |= __put_user(fp_to, &frame->uc.uc_mcontext.fpstate);
 	if (sizeof(*set) == 16) {
diff --git a/arch/x86/um/user-offsets.c b/arch/x86/um/user-offsets.c
index 1c77d9946199..d6e1cd9956bf 100644
--- a/arch/x86/um/user-offsets.c
+++ b/arch/x86/um/user-offsets.c
@@ -20,9 +20,6 @@ void foo(void);
 void foo(void)
 {
 #ifdef __i386__
-	DEFINE_LONGS(HOST_FP_SIZE, sizeof(struct user_fpregs_struct));
-	DEFINE_LONGS(HOST_FPX_SIZE, sizeof(struct user_fpxregs_struct));
-
 	DEFINE(HOST_IP, EIP);
 	DEFINE(HOST_SP, UESP);
 	DEFINE(HOST_EFLAGS, EFL);
@@ -41,11 +38,6 @@ void foo(void)
 	DEFINE(HOST_GS, GS);
 	DEFINE(HOST_ORIG_AX, ORIG_EAX);
 #else
-#ifdef FP_XSTATE_MAGIC1
-	DEFINE_LONGS(HOST_FP_SIZE, 2696);
-#else
-	DEFINE(HOST_FP_SIZE, sizeof(struct _fpstate) / sizeof(unsigned long));
-#endif
 	DEFINE_LONGS(HOST_BX, RBX);
 	DEFINE_LONGS(HOST_CX, RCX);
 	DEFINE_LONGS(HOST_DI, RDI);