target/arm/arch_dump.c - third_party/qemu - Git at Google

 /* Support for writing ELF notes for ARM architectures
  *
  * Copyright (C) 2015 Red Hat Inc.
  *
  * Author: Andrew Jones <drjones@redhat.com>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation; either version 2 of the License, or
  * (at your option) any later version.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License along
  * with this program; if not, see <http://www.gnu.org/licenses/>.
  */

 #include "qemu/osdep.h"
 #include "cpu.h"
 #include "elf.h"
 #include "sysemu/dump.h"

 /* struct user_pt_regs from arch/arm64/include/uapi/asm/ptrace.h */
 struct aarch64_user_regs {
     uint64_t regs[31];
     uint64_t sp;
     uint64_t pc;
     uint64_t pstate;
 } QEMU_PACKED;

 QEMU_BUILD_BUG_ON(sizeof(struct aarch64_user_regs) != 272);

 /* struct elf_prstatus from include/uapi/linux/elfcore.h */
 struct aarch64_elf_prstatus {
     char pad1[32]; /* 32 == offsetof(struct elf_prstatus, pr_pid) */
     uint32_t pr_pid;
     char pad2[76]; /* 76 == offsetof(struct elf_prstatus, pr_reg) -
                             offsetof(struct elf_prstatus, pr_ppid) */
     struct aarch64_user_regs pr_reg;
     uint32_t pr_fpvalid;
     char pad3[4];
 } QEMU_PACKED;

 QEMU_BUILD_BUG_ON(sizeof(struct aarch64_elf_prstatus) != 392);

 /* struct user_fpsimd_state from arch/arm64/include/uapi/asm/ptrace.h
  *
  * While the vregs member of user_fpsimd_state is of type __uint128_t,
  * QEMU uses an array of uint64_t, where the high half of the 128-bit
  * value is always in the 2n+1'th index. Thus we also break the 128-
  * bit values into two halves in this reproduction of user_fpsimd_state.
  */
 struct aarch64_user_vfp_state {
     uint64_t vregs[64];
     uint32_t fpsr;
     uint32_t fpcr;
     char pad[8];
 } QEMU_PACKED;

 QEMU_BUILD_BUG_ON(sizeof(struct aarch64_user_vfp_state) != 528);

 /* struct user_sve_header from arch/arm64/include/uapi/asm/ptrace.h */
 struct aarch64_user_sve_header {
     uint32_t size;
     uint32_t max_size;
     uint16_t vl;
     uint16_t max_vl;
     uint16_t flags;
     uint16_t reserved;
 } QEMU_PACKED;

 struct aarch64_note {
     Elf64_Nhdr hdr;
     char name[8]; /* align_up(sizeof("CORE"), 4) */
     union {
         struct aarch64_elf_prstatus prstatus;
         struct aarch64_user_vfp_state vfp;
         struct aarch64_user_sve_header sve;
     };
 } QEMU_PACKED;

 #define AARCH64_NOTE_HEADER_SIZE offsetof(struct aarch64_note, prstatus)
 #define AARCH64_PRSTATUS_NOTE_SIZE \
             (AARCH64_NOTE_HEADER_SIZE + sizeof(struct aarch64_elf_prstatus))
 #define AARCH64_PRFPREG_NOTE_SIZE \
             (AARCH64_NOTE_HEADER_SIZE + sizeof(struct aarch64_user_vfp_state))
 #define AARCH64_SVE_NOTE_SIZE(env) \
             (AARCH64_NOTE_HEADER_SIZE + sve_size(env))

 static void aarch64_note_init(struct aarch64_note *note, DumpState *s,
                               const char *name, Elf64_Word namesz,
                               Elf64_Word type, Elf64_Word descsz)
 {
     memset(note, 0, sizeof(*note));

     note->hdr.n_namesz = cpu_to_dump32(s, namesz);
     note->hdr.n_descsz = cpu_to_dump32(s, descsz);
     note->hdr.n_type = cpu_to_dump32(s, type);

     memcpy(note->name, name, namesz);
 }

 static int aarch64_write_elf64_prfpreg(WriteCoreDumpFunction f,
                                        CPUARMState *env, int cpuid,
                                        DumpState *s)
 {
     struct aarch64_note note;
     int ret, i;

     aarch64_note_init(&note, s, "CORE", 5, NT_PRFPREG, sizeof(note.vfp));

     for (i = 0; i < 32; ++i) {
         uint64_t *q = aa64_vfp_qreg(env, i);
         note.vfp.vregs[2*i + 0] = cpu_to_dump64(s, q[0]);
         note.vfp.vregs[2*i + 1] = cpu_to_dump64(s, q[1]);
     }

     if (s->dump_info.d_endian == ELFDATA2MSB) {
         /* For AArch64 we must always swap the vfp.regs's 2n and 2n+1
          * entries when generating BE notes, because even big endian
          * hosts use 2n+1 for the high half.
          */
         for (i = 0; i < 32; ++i) {
             uint64_t tmp = note.vfp.vregs[2*i];
             note.vfp.vregs[2*i] = note.vfp.vregs[2*i+1];
             note.vfp.vregs[2*i+1] = tmp;
         }
     }

     note.vfp.fpsr = cpu_to_dump32(s, vfp_get_fpsr(env));
     note.vfp.fpcr = cpu_to_dump32(s, vfp_get_fpcr(env));

     ret = f(&note, AARCH64_PRFPREG_NOTE_SIZE, s);
     if (ret < 0) {
         return -1;
     }

     return 0;
 }

 #ifdef TARGET_AARCH64
 static off_t sve_zreg_offset(uint32_t vq, int n)
 {
     off_t off = sizeof(struct aarch64_user_sve_header);
     return ROUND_UP(off, 16) + vq * 16 * n;
 }

 static off_t sve_preg_offset(uint32_t vq, int n)
 {
     return sve_zreg_offset(vq, 32) + vq * 16 / 8 * n;
 }

 static off_t sve_fpsr_offset(uint32_t vq)
 {
     off_t off = sve_preg_offset(vq, 17);
     return ROUND_UP(off, 16);
 }

 static off_t sve_fpcr_offset(uint32_t vq)
 {
     return sve_fpsr_offset(vq) + sizeof(uint32_t);
 }

 static uint32_t sve_current_vq(CPUARMState *env)
 {
     return sve_zcr_len_for_el(env, arm_current_el(env)) + 1;
 }

 static size_t sve_size_vq(uint32_t vq)
 {
     off_t off = sve_fpcr_offset(vq) + sizeof(uint32_t);
     return ROUND_UP(off, 16);
 }

 static size_t sve_size(CPUARMState *env)
 {
     return sve_size_vq(sve_current_vq(env));
 }

 static int aarch64_write_elf64_sve(WriteCoreDumpFunction f,
                                    CPUARMState *env, int cpuid,
                                    DumpState *s)
 {
     struct aarch64_note *note;
     ARMCPU *cpu = env_archcpu(env);
     uint32_t vq = sve_current_vq(env);
     uint64_t tmp[ARM_MAX_VQ * 2], *r;
     uint32_t fpr;
     uint8_t *buf;
     int ret, i;

     note = g_malloc0(AARCH64_SVE_NOTE_SIZE(env));
     buf = (uint8_t *)&note->sve;

     aarch64_note_init(note, s, "LINUX", 6, NT_ARM_SVE, sve_size_vq(vq));

     note->sve.size = cpu_to_dump32(s, sve_size_vq(vq));
     note->sve.max_size = cpu_to_dump32(s, sve_size_vq(cpu->sve_max_vq));
     note->sve.vl = cpu_to_dump16(s, vq * 16);
     note->sve.max_vl = cpu_to_dump16(s, cpu->sve_max_vq * 16);
     note->sve.flags = cpu_to_dump16(s, 1);

     for (i = 0; i < 32; ++i) {
         r = sve_bswap64(tmp, &env->vfp.zregs[i].d[0], vq * 2);
         memcpy(&buf[sve_zreg_offset(vq, i)], r, vq * 16);
     }

     for (i = 0; i < 17; ++i) {
         r = sve_bswap64(tmp, r = &env->vfp.pregs[i].p[0],
                         DIV_ROUND_UP(vq * 2, 8));
         memcpy(&buf[sve_preg_offset(vq, i)], r, vq * 16 / 8);
     }

     fpr = cpu_to_dump32(s, vfp_get_fpsr(env));
     memcpy(&buf[sve_fpsr_offset(vq)], &fpr, sizeof(uint32_t));

     fpr = cpu_to_dump32(s, vfp_get_fpcr(env));
     memcpy(&buf[sve_fpcr_offset(vq)], &fpr, sizeof(uint32_t));

     ret = f(note, AARCH64_SVE_NOTE_SIZE(env), s);
     g_free(note);

     if (ret < 0) {
         return -1;
     }

     return 0;
 }
 #endif

 int arm_cpu_write_elf64_note(WriteCoreDumpFunction f, CPUState *cs,
                              int cpuid, void *opaque)
 {
     struct aarch64_note note;
     ARMCPU *cpu = ARM_CPU(cs);
     CPUARMState *env = &cpu->env;
     DumpState *s = opaque;
     uint64_t pstate, sp;
     int ret, i;

     aarch64_note_init(&note, s, "CORE", 5, NT_PRSTATUS, sizeof(note.prstatus));

     note.prstatus.pr_pid = cpu_to_dump32(s, cpuid);
     note.prstatus.pr_fpvalid = cpu_to_dump32(s, 1);

     if (!is_a64(env)) {
         aarch64_sync_32_to_64(env);
         pstate = cpsr_read(env);
         sp = 0;
     } else {
         pstate = pstate_read(env);
         sp = env->xregs[31];
     }

     for (i = 0; i < 31; ++i) {
         note.prstatus.pr_reg.regs[i] = cpu_to_dump64(s, env->xregs[i]);
     }
     note.prstatus.pr_reg.sp = cpu_to_dump64(s, sp);
     note.prstatus.pr_reg.pc = cpu_to_dump64(s, env->pc);
     note.prstatus.pr_reg.pstate = cpu_to_dump64(s, pstate);

     ret = f(&note, AARCH64_PRSTATUS_NOTE_SIZE, s);
     if (ret < 0) {
         return -1;
     }

     ret = aarch64_write_elf64_prfpreg(f, env, cpuid, s);
     if (ret) {
         return ret;
     }

 #ifdef TARGET_AARCH64
     if (cpu_isar_feature(aa64_sve, cpu)) {
         ret = aarch64_write_elf64_sve(f, env, cpuid, s);
     }
 #endif

     return ret;
 }

 /* struct pt_regs from arch/arm/include/asm/ptrace.h */
 struct arm_user_regs {
     uint32_t regs[17];
     char pad[4];
 } QEMU_PACKED;

 QEMU_BUILD_BUG_ON(sizeof(struct arm_user_regs) != 72);

 /* struct elf_prstatus from include/uapi/linux/elfcore.h */
 struct arm_elf_prstatus {
     char pad1[24]; /* 24 == offsetof(struct elf_prstatus, pr_pid) */
     uint32_t pr_pid;
     char pad2[44]; /* 44 == offsetof(struct elf_prstatus, pr_reg) -
                             offsetof(struct elf_prstatus, pr_ppid) */
     struct arm_user_regs pr_reg;
     uint32_t pr_fpvalid;
 } QEMU_PACKED arm_elf_prstatus;

 QEMU_BUILD_BUG_ON(sizeof(struct arm_elf_prstatus) != 148);

 /* struct user_vfp from arch/arm/include/asm/user.h */
 struct arm_user_vfp_state {
     uint64_t vregs[32];
     uint32_t fpscr;
 } QEMU_PACKED;

 QEMU_BUILD_BUG_ON(sizeof(struct arm_user_vfp_state) != 260);

 struct arm_note {
     Elf32_Nhdr hdr;
     char name[8]; /* align_up(sizeof("LINUX"), 4) */
     union {
         struct arm_elf_prstatus prstatus;
         struct arm_user_vfp_state vfp;
     };
 } QEMU_PACKED;

 #define ARM_NOTE_HEADER_SIZE offsetof(struct arm_note, prstatus)
 #define ARM_PRSTATUS_NOTE_SIZE \
             (ARM_NOTE_HEADER_SIZE + sizeof(struct arm_elf_prstatus))
 #define ARM_VFP_NOTE_SIZE \
             (ARM_NOTE_HEADER_SIZE + sizeof(struct arm_user_vfp_state))

 static void arm_note_init(struct arm_note *note, DumpState *s,
                           const char *name, Elf32_Word namesz,
                           Elf32_Word type, Elf32_Word descsz)
 {
     memset(note, 0, sizeof(*note));

     note->hdr.n_namesz = cpu_to_dump32(s, namesz);
     note->hdr.n_descsz = cpu_to_dump32(s, descsz);
     note->hdr.n_type = cpu_to_dump32(s, type);

     memcpy(note->name, name, namesz);
 }

 static int arm_write_elf32_vfp(WriteCoreDumpFunction f, CPUARMState *env,
                                int cpuid, DumpState *s)
 {
     struct arm_note note;
     int ret, i;

     arm_note_init(&note, s, "LINUX", 6, NT_ARM_VFP, sizeof(note.vfp));

     for (i = 0; i < 32; ++i) {
         note.vfp.vregs[i] = cpu_to_dump64(s, *aa32_vfp_dreg(env, i));
     }

     note.vfp.fpscr = cpu_to_dump32(s, vfp_get_fpscr(env));

     ret = f(&note, ARM_VFP_NOTE_SIZE, s);
     if (ret < 0) {
         return -1;
     }

     return 0;
 }

 int arm_cpu_write_elf32_note(WriteCoreDumpFunction f, CPUState *cs,
                              int cpuid, void *opaque)
 {
     struct arm_note note;
     ARMCPU *cpu = ARM_CPU(cs);
     CPUARMState *env = &cpu->env;
     DumpState *s = opaque;
     int ret, i;
     bool fpvalid = cpu_isar_feature(aa32_vfp_simd, cpu);

     arm_note_init(&note, s, "CORE", 5, NT_PRSTATUS, sizeof(note.prstatus));

     note.prstatus.pr_pid = cpu_to_dump32(s, cpuid);
     note.prstatus.pr_fpvalid = cpu_to_dump32(s, fpvalid);

     for (i = 0; i < 16; ++i) {
         note.prstatus.pr_reg.regs[i] = cpu_to_dump32(s, env->regs[i]);
     }
     note.prstatus.pr_reg.regs[16] = cpu_to_dump32(s, cpsr_read(env));

     ret = f(&note, ARM_PRSTATUS_NOTE_SIZE, s);
     if (ret < 0) {
         return -1;
     } else if (fpvalid) {
         return arm_write_elf32_vfp(f, env, cpuid, s);
     }

     return 0;
 }

 int cpu_get_dump_info(ArchDumpInfo *info,
                       const GuestPhysBlockList *guest_phys_blocks)
 {
     ARMCPU *cpu;
     CPUARMState *env;
     GuestPhysBlock *block;
     hwaddr lowest_addr = ULLONG_MAX;

     if (first_cpu == NULL) {
         return -1;
     }

     cpu = ARM_CPU(first_cpu);
     env = &cpu->env;

     /* Take a best guess at the phys_base. If we get it wrong then crash
      * will need '--machdep phys_offset=<phys-offset>' added to its command
      * line, which isn't any worse than assuming we can use zero, but being
      * wrong. This is the same algorithm the crash utility uses when
      * attempting to guess as it loads non-dumpfile formatted files.
      */
     QTAILQ_FOREACH(block, &guest_phys_blocks->head, next) {
         if (block->target_start < lowest_addr) {
             lowest_addr = block->target_start;
         }
     }

     if (arm_feature(env, ARM_FEATURE_AARCH64)) {
         info->d_machine = EM_AARCH64;
         info->d_class = ELFCLASS64;
         info->page_size = (1 << 16); /* aarch64 max pagesize */
         if (lowest_addr != ULLONG_MAX) {
             info->phys_base = lowest_addr;
         }
     } else {
         info->d_machine = EM_ARM;
         info->d_class = ELFCLASS32;
         info->page_size = (1 << 12);
         if (lowest_addr < UINT_MAX) {
             info->phys_base = lowest_addr;
         }
     }

     /* We assume the relevant endianness is that of EL1; this is right
      * for kernels, but might give the wrong answer if you're trying to
      * dump a hypervisor that happens to be running an opposite-endian
      * kernel.
      */
     info->d_endian = (env->cp15.sctlr_el[1] & SCTLR_EE) != 0
                      ? ELFDATA2MSB : ELFDATA2LSB;

     return 0;
 }

 ssize_t cpu_get_note_size(int class, int machine, int nr_cpus)
 {
     ARMCPU *cpu = ARM_CPU(first_cpu);
     size_t note_size;

     if (class == ELFCLASS64) {
         note_size = AARCH64_PRSTATUS_NOTE_SIZE;
         note_size += AARCH64_PRFPREG_NOTE_SIZE;
 #ifdef TARGET_AARCH64
         if (cpu_isar_feature(aa64_sve, cpu)) {
             note_size += AARCH64_SVE_NOTE_SIZE(&cpu->env);
         }
 #endif
     } else {
         note_size = ARM_PRSTATUS_NOTE_SIZE;
         if (cpu_isar_feature(aa32_vfp_simd, cpu)) {
             note_size += ARM_VFP_NOTE_SIZE;
         }
     }

     return note_size * nr_cpus;
 }
	/* Support for writing ELF notes for ARM architectures
	*
	* Copyright (C) 2015 Red Hat Inc.
	*
	* Author: Andrew Jones <drjones@redhat.com>
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License as published by
	* the Free Software Foundation; either version 2 of the License, or
	* (at your option) any later version.
	*
	* This program is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	* GNU General Public License for more details.
	*
	* You should have received a copy of the GNU General Public License along
	* with this program; if not, see <http://www.gnu.org/licenses/>.
	*/

	#include "qemu/osdep.h"
	#include "cpu.h"
	#include "elf.h"
	#include "sysemu/dump.h"

	/* struct user_pt_regs from arch/arm64/include/uapi/asm/ptrace.h */
	struct aarch64_user_regs {
	uint64_t regs[31];
	uint64_t sp;
	uint64_t pc;
	uint64_t pstate;
	} QEMU_PACKED;

	QEMU_BUILD_BUG_ON(sizeof(struct aarch64_user_regs) != 272);

	/* struct elf_prstatus from include/uapi/linux/elfcore.h */
	struct aarch64_elf_prstatus {
	char pad1[32]; /* 32 == offsetof(struct elf_prstatus, pr_pid) */
	uint32_t pr_pid;
	char pad2[76]; /* 76 == offsetof(struct elf_prstatus, pr_reg) -
	offsetof(struct elf_prstatus, pr_ppid) */
	struct aarch64_user_regs pr_reg;
	uint32_t pr_fpvalid;
	char pad3[4];
	} QEMU_PACKED;

	QEMU_BUILD_BUG_ON(sizeof(struct aarch64_elf_prstatus) != 392);

	/* struct user_fpsimd_state from arch/arm64/include/uapi/asm/ptrace.h
	*
	* While the vregs member of user_fpsimd_state is of type __uint128_t,
	* QEMU uses an array of uint64_t, where the high half of the 128-bit
	* value is always in the 2n+1'th index. Thus we also break the 128-
	* bit values into two halves in this reproduction of user_fpsimd_state.
	*/
	struct aarch64_user_vfp_state {
	uint64_t vregs[64];
	uint32_t fpsr;
	uint32_t fpcr;
	char pad[8];
	} QEMU_PACKED;

	QEMU_BUILD_BUG_ON(sizeof(struct aarch64_user_vfp_state) != 528);

	/* struct user_sve_header from arch/arm64/include/uapi/asm/ptrace.h */
	struct aarch64_user_sve_header {
	uint32_t size;
	uint32_t max_size;
	uint16_t vl;
	uint16_t max_vl;
	uint16_t flags;
	uint16_t reserved;
	} QEMU_PACKED;

	struct aarch64_note {
	Elf64_Nhdr hdr;
	char name[8]; /* align_up(sizeof("CORE"), 4) */
	union {
	struct aarch64_elf_prstatus prstatus;
	struct aarch64_user_vfp_state vfp;
	struct aarch64_user_sve_header sve;
	};
	} QEMU_PACKED;

	#define AARCH64_NOTE_HEADER_SIZE offsetof(struct aarch64_note, prstatus)
	#define AARCH64_PRSTATUS_NOTE_SIZE \
	(AARCH64_NOTE_HEADER_SIZE + sizeof(struct aarch64_elf_prstatus))
	#define AARCH64_PRFPREG_NOTE_SIZE \
	(AARCH64_NOTE_HEADER_SIZE + sizeof(struct aarch64_user_vfp_state))
	#define AARCH64_SVE_NOTE_SIZE(env) \
	(AARCH64_NOTE_HEADER_SIZE + sve_size(env))

	static void aarch64_note_init(struct aarch64_note note, DumpState s,
	const char *name, Elf64_Word namesz,
	Elf64_Word type, Elf64_Word descsz)
	{
	memset(note, 0, sizeof(*note));

	note->hdr.n_namesz = cpu_to_dump32(s, namesz);
	note->hdr.n_descsz = cpu_to_dump32(s, descsz);
	note->hdr.n_type = cpu_to_dump32(s, type);

	memcpy(note->name, name, namesz);
	}

	static int aarch64_write_elf64_prfpreg(WriteCoreDumpFunction f,
	CPUARMState *env, int cpuid,
	DumpState *s)
	{
	struct aarch64_note note;
	int ret, i;

	aarch64_note_init(&note, s, "CORE", 5, NT_PRFPREG, sizeof(note.vfp));

	for (i = 0; i < 32; ++i) {
	uint64_t *q = aa64_vfp_qreg(env, i);
	note.vfp.vregs[2*i + 0] = cpu_to_dump64(s, q[0]);
	note.vfp.vregs[2*i + 1] = cpu_to_dump64(s, q[1]);
	}

	if (s->dump_info.d_endian == ELFDATA2MSB) {
	/* For AArch64 we must always swap the vfp.regs's 2n and 2n+1
	* entries when generating BE notes, because even big endian
	* hosts use 2n+1 for the high half.
	*/
	for (i = 0; i < 32; ++i) {
	uint64_t tmp = note.vfp.vregs[2*i];
	note.vfp.vregs[2i] = note.vfp.vregs[2i+1];
	note.vfp.vregs[2*i+1] = tmp;
	}
	}

	note.vfp.fpsr = cpu_to_dump32(s, vfp_get_fpsr(env));
	note.vfp.fpcr = cpu_to_dump32(s, vfp_get_fpcr(env));

	ret = f(&note, AARCH64_PRFPREG_NOTE_SIZE, s);
	if (ret < 0) {
	return -1;
	}

	return 0;
	}

	#ifdef TARGET_AARCH64
	static off_t sve_zreg_offset(uint32_t vq, int n)
	{
	off_t off = sizeof(struct aarch64_user_sve_header);
	return ROUND_UP(off, 16) + vq * 16 * n;
	}

	static off_t sve_preg_offset(uint32_t vq, int n)
	{
	return sve_zreg_offset(vq, 32) + vq * 16 / 8 * n;
	}

	static off_t sve_fpsr_offset(uint32_t vq)
	{
	off_t off = sve_preg_offset(vq, 17);
	return ROUND_UP(off, 16);
	}

	static off_t sve_fpcr_offset(uint32_t vq)
	{
	return sve_fpsr_offset(vq) + sizeof(uint32_t);
	}

	static uint32_t sve_current_vq(CPUARMState *env)
	{
	return sve_zcr_len_for_el(env, arm_current_el(env)) + 1;
	}

	static size_t sve_size_vq(uint32_t vq)
	{
	off_t off = sve_fpcr_offset(vq) + sizeof(uint32_t);
	return ROUND_UP(off, 16);
	}

	static size_t sve_size(CPUARMState *env)
	{
	return sve_size_vq(sve_current_vq(env));
	}

	static int aarch64_write_elf64_sve(WriteCoreDumpFunction f,
	CPUARMState *env, int cpuid,
	DumpState *s)
	{
	struct aarch64_note *note;
	ARMCPU *cpu = env_archcpu(env);
	uint32_t vq = sve_current_vq(env);
	uint64_t tmp[ARM_MAX_VQ * 2], *r;
	uint32_t fpr;
	uint8_t *buf;
	int ret, i;

	note = g_malloc0(AARCH64_SVE_NOTE_SIZE(env));
	buf = (uint8_t *)&note->sve;

	aarch64_note_init(note, s, "LINUX", 6, NT_ARM_SVE, sve_size_vq(vq));

	note->sve.size = cpu_to_dump32(s, sve_size_vq(vq));
	note->sve.max_size = cpu_to_dump32(s, sve_size_vq(cpu->sve_max_vq));
	note->sve.vl = cpu_to_dump16(s, vq * 16);
	note->sve.max_vl = cpu_to_dump16(s, cpu->sve_max_vq * 16);
	note->sve.flags = cpu_to_dump16(s, 1);

	for (i = 0; i < 32; ++i) {
	r = sve_bswap64(tmp, &env->vfp.zregs[i].d[0], vq * 2);
	memcpy(&buf[sve_zreg_offset(vq, i)], r, vq * 16);
	}

	for (i = 0; i < 17; ++i) {
	r = sve_bswap64(tmp, r = &env->vfp.pregs[i].p[0],
	DIV_ROUND_UP(vq * 2, 8));
	memcpy(&buf[sve_preg_offset(vq, i)], r, vq * 16 / 8);
	}

	fpr = cpu_to_dump32(s, vfp_get_fpsr(env));
	memcpy(&buf[sve_fpsr_offset(vq)], &fpr, sizeof(uint32_t));

	fpr = cpu_to_dump32(s, vfp_get_fpcr(env));
	memcpy(&buf[sve_fpcr_offset(vq)], &fpr, sizeof(uint32_t));

	ret = f(note, AARCH64_SVE_NOTE_SIZE(env), s);
	g_free(note);

	if (ret < 0) {
	return -1;
	}

	return 0;
	}
	#endif

	int arm_cpu_write_elf64_note(WriteCoreDumpFunction f, CPUState *cs,
	int cpuid, void *opaque)
	{
	struct aarch64_note note;
	ARMCPU *cpu = ARM_CPU(cs);
	CPUARMState *env = &cpu->env;
	DumpState *s = opaque;
	uint64_t pstate, sp;
	int ret, i;

	aarch64_note_init(&note, s, "CORE", 5, NT_PRSTATUS, sizeof(note.prstatus));

	note.prstatus.pr_pid = cpu_to_dump32(s, cpuid);
	note.prstatus.pr_fpvalid = cpu_to_dump32(s, 1);

	if (!is_a64(env)) {
	aarch64_sync_32_to_64(env);
	pstate = cpsr_read(env);
	sp = 0;
	} else {
	pstate = pstate_read(env);
	sp = env->xregs[31];
	}

	for (i = 0; i < 31; ++i) {
	note.prstatus.pr_reg.regs[i] = cpu_to_dump64(s, env->xregs[i]);
	}
	note.prstatus.pr_reg.sp = cpu_to_dump64(s, sp);
	note.prstatus.pr_reg.pc = cpu_to_dump64(s, env->pc);
	note.prstatus.pr_reg.pstate = cpu_to_dump64(s, pstate);

	ret = f(&note, AARCH64_PRSTATUS_NOTE_SIZE, s);
	if (ret < 0) {
	return -1;
	}

	ret = aarch64_write_elf64_prfpreg(f, env, cpuid, s);
	if (ret) {
	return ret;
	}

	#ifdef TARGET_AARCH64
	if (cpu_isar_feature(aa64_sve, cpu)) {
	ret = aarch64_write_elf64_sve(f, env, cpuid, s);
	}
	#endif

	return ret;
	}

	/* struct pt_regs from arch/arm/include/asm/ptrace.h */
	struct arm_user_regs {
	uint32_t regs[17];
	char pad[4];
	} QEMU_PACKED;

	QEMU_BUILD_BUG_ON(sizeof(struct arm_user_regs) != 72);

	/* struct elf_prstatus from include/uapi/linux/elfcore.h */
	struct arm_elf_prstatus {
	char pad1[24]; /* 24 == offsetof(struct elf_prstatus, pr_pid) */
	uint32_t pr_pid;
	char pad2[44]; /* 44 == offsetof(struct elf_prstatus, pr_reg) -
	offsetof(struct elf_prstatus, pr_ppid) */
	struct arm_user_regs pr_reg;
	uint32_t pr_fpvalid;
	} QEMU_PACKED arm_elf_prstatus;

	QEMU_BUILD_BUG_ON(sizeof(struct arm_elf_prstatus) != 148);

	/* struct user_vfp from arch/arm/include/asm/user.h */
	struct arm_user_vfp_state {
	uint64_t vregs[32];
	uint32_t fpscr;
	} QEMU_PACKED;

	QEMU_BUILD_BUG_ON(sizeof(struct arm_user_vfp_state) != 260);

	struct arm_note {
	Elf32_Nhdr hdr;
	char name[8]; /* align_up(sizeof("LINUX"), 4) */
	union {
	struct arm_elf_prstatus prstatus;
	struct arm_user_vfp_state vfp;
	};
	} QEMU_PACKED;

	#define ARM_NOTE_HEADER_SIZE offsetof(struct arm_note, prstatus)
	#define ARM_PRSTATUS_NOTE_SIZE \
	(ARM_NOTE_HEADER_SIZE + sizeof(struct arm_elf_prstatus))
	#define ARM_VFP_NOTE_SIZE \
	(ARM_NOTE_HEADER_SIZE + sizeof(struct arm_user_vfp_state))

	static void arm_note_init(struct arm_note note, DumpState s,
	const char *name, Elf32_Word namesz,
	Elf32_Word type, Elf32_Word descsz)
	{
	memset(note, 0, sizeof(*note));

	note->hdr.n_namesz = cpu_to_dump32(s, namesz);
	note->hdr.n_descsz = cpu_to_dump32(s, descsz);
	note->hdr.n_type = cpu_to_dump32(s, type);

	memcpy(note->name, name, namesz);
	}

	static int arm_write_elf32_vfp(WriteCoreDumpFunction f, CPUARMState *env,
	int cpuid, DumpState *s)
	{
	struct arm_note note;
	int ret, i;

	arm_note_init(&note, s, "LINUX", 6, NT_ARM_VFP, sizeof(note.vfp));

	for (i = 0; i < 32; ++i) {
	note.vfp.vregs[i] = cpu_to_dump64(s, *aa32_vfp_dreg(env, i));
	}

	note.vfp.fpscr = cpu_to_dump32(s, vfp_get_fpscr(env));

	ret = f(&note, ARM_VFP_NOTE_SIZE, s);
	if (ret < 0) {
	return -1;
	}

	return 0;
	}

	int arm_cpu_write_elf32_note(WriteCoreDumpFunction f, CPUState *cs,
	int cpuid, void *opaque)
	{
	struct arm_note note;
	ARMCPU *cpu = ARM_CPU(cs);
	CPUARMState *env = &cpu->env;
	DumpState *s = opaque;
	int ret, i;
	bool fpvalid = cpu_isar_feature(aa32_vfp_simd, cpu);

	arm_note_init(&note, s, "CORE", 5, NT_PRSTATUS, sizeof(note.prstatus));

	note.prstatus.pr_pid = cpu_to_dump32(s, cpuid);
	note.prstatus.pr_fpvalid = cpu_to_dump32(s, fpvalid);

	for (i = 0; i < 16; ++i) {
	note.prstatus.pr_reg.regs[i] = cpu_to_dump32(s, env->regs[i]);
	}
	note.prstatus.pr_reg.regs[16] = cpu_to_dump32(s, cpsr_read(env));

	ret = f(&note, ARM_PRSTATUS_NOTE_SIZE, s);
	if (ret < 0) {
	return -1;
	} else if (fpvalid) {
	return arm_write_elf32_vfp(f, env, cpuid, s);
	}

	return 0;
	}

	int cpu_get_dump_info(ArchDumpInfo *info,
	const GuestPhysBlockList *guest_phys_blocks)
	{
	ARMCPU *cpu;
	CPUARMState *env;
	GuestPhysBlock *block;
	hwaddr lowest_addr = ULLONG_MAX;

	if (first_cpu == NULL) {
	return -1;
	}

	cpu = ARM_CPU(first_cpu);
	env = &cpu->env;

	/* Take a best guess at the phys_base. If we get it wrong then crash
	* will need '--machdep phys_offset=<phys-offset>' added to its command
	* line, which isn't any worse than assuming we can use zero, but being
	* wrong. This is the same algorithm the crash utility uses when
	* attempting to guess as it loads non-dumpfile formatted files.
	*/
	QTAILQ_FOREACH(block, &guest_phys_blocks->head, next) {
	if (block->target_start < lowest_addr) {
	lowest_addr = block->target_start;
	}
	}

	if (arm_feature(env, ARM_FEATURE_AARCH64)) {
	info->d_machine = EM_AARCH64;
	info->d_class = ELFCLASS64;
	info->page_size = (1 << 16); /* aarch64 max pagesize */
	if (lowest_addr != ULLONG_MAX) {
	info->phys_base = lowest_addr;
	}
	} else {
	info->d_machine = EM_ARM;
	info->d_class = ELFCLASS32;
	info->page_size = (1 << 12);
	if (lowest_addr < UINT_MAX) {
	info->phys_base = lowest_addr;
	}
	}

	/* We assume the relevant endianness is that of EL1; this is right
	* for kernels, but might give the wrong answer if you're trying to
	* dump a hypervisor that happens to be running an opposite-endian
	* kernel.
	*/
	info->d_endian = (env->cp15.sctlr_el[1] & SCTLR_EE) != 0
	? ELFDATA2MSB : ELFDATA2LSB;

	return 0;
	}

	ssize_t cpu_get_note_size(int class, int machine, int nr_cpus)
	{
	ARMCPU *cpu = ARM_CPU(first_cpu);
	size_t note_size;

	if (class == ELFCLASS64) {
	note_size = AARCH64_PRSTATUS_NOTE_SIZE;
	note_size += AARCH64_PRFPREG_NOTE_SIZE;
	#ifdef TARGET_AARCH64
	if (cpu_isar_feature(aa64_sve, cpu)) {
	note_size += AARCH64_SVE_NOTE_SIZE(&cpu->env);
	}
	#endif
	} else {
	note_size = ARM_PRSTATUS_NOTE_SIZE;
	if (cpu_isar_feature(aa32_vfp_simd, cpu)) {
	note_size += ARM_VFP_NOTE_SIZE;
	}
	}

	return note_size * nr_cpus;
	}