freebsd-nq/lib/libkvm/kvm_amd64.c
John Baldwin ad3ecc2025 Fix parsing of a 1GB page table entry.
Use 'pdpe' to extract the PA of the 1GB page instead of 'pde' (which was
a copy and paste bug from the 2MB page case further down).

CID:		1341467
Reported by:	pfg
2016-03-28 18:41:48 +00:00

333 lines
8.4 KiB
C

/*-
* Copyright (c) 1989, 1992, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software developed by the Computer Systems
* Engineering group at Lawrence Berkeley Laboratory under DARPA contract
* BG 91-66 and contributed to Berkeley.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#if defined(LIBC_SCCS) && !defined(lint)
#if 0
static char sccsid[] = "@(#)kvm_hp300.c 8.1 (Berkeley) 6/4/93";
#endif
#endif /* LIBC_SCCS and not lint */
/*
* AMD64 machine dependent routines for kvm. Hopefully, the forthcoming
* vm code will one day obsolete this module.
*/
#include <sys/param.h>
#include <sys/endian.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <kvm.h>
#include <limits.h>
#include "kvm_private.h"
#include "kvm_amd64.h"
struct vmstate {
size_t phnum;
GElf_Phdr *phdr;
amd64_pml4e_t *PML4;
};
/*
* Translate a physical memory address to a file-offset in the crash-dump.
*/
static size_t
_kvm_pa2off(kvm_t *kd, uint64_t pa, off_t *ofs)
{
struct vmstate *vm = kd->vmst;
GElf_Phdr *p;
size_t n;
if (kd->rawdump) {
*ofs = pa;
return (AMD64_PAGE_SIZE - (pa & AMD64_PAGE_MASK));
}
p = vm->phdr;
n = vm->phnum;
while (n && (pa < p->p_paddr || pa >= p->p_paddr + p->p_memsz))
p++, n--;
if (n == 0)
return (0);
*ofs = (pa - p->p_paddr) + p->p_offset;
return (AMD64_PAGE_SIZE - (pa & AMD64_PAGE_MASK));
}
static void
_amd64_freevtop(kvm_t *kd)
{
struct vmstate *vm = kd->vmst;
if (vm->PML4)
free(vm->PML4);
free(vm->phdr);
free(vm);
kd->vmst = NULL;
}
static int
_amd64_probe(kvm_t *kd)
{
return (_kvm_probe_elf_kernel(kd, ELFCLASS64, EM_X86_64) &&
!_kvm_is_minidump(kd));
}
static int
_amd64_initvtop(kvm_t *kd)
{
struct kvm_nlist nl[2];
amd64_physaddr_t pa;
kvaddr_t kernbase;
amd64_pml4e_t *PML4;
kd->vmst = (struct vmstate *)_kvm_malloc(kd, sizeof(*kd->vmst));
if (kd->vmst == 0) {
_kvm_err(kd, kd->program, "cannot allocate vm");
return (-1);
}
kd->vmst->PML4 = 0;
if (kd->rawdump == 0) {
if (_kvm_read_core_phdrs(kd, &kd->vmst->phnum,
&kd->vmst->phdr) == -1)
return (-1);
}
nl[0].n_name = "kernbase";
nl[1].n_name = 0;
if (kvm_nlist2(kd, nl) != 0) {
_kvm_err(kd, kd->program, "bad namelist - no kernbase");
return (-1);
}
kernbase = nl[0].n_value;
nl[0].n_name = "KPML4phys";
nl[1].n_name = 0;
if (kvm_nlist2(kd, nl) != 0) {
_kvm_err(kd, kd->program, "bad namelist - no KPML4phys");
return (-1);
}
if (kvm_read2(kd, (nl[0].n_value - kernbase), &pa, sizeof(pa)) !=
sizeof(pa)) {
_kvm_err(kd, kd->program, "cannot read KPML4phys");
return (-1);
}
pa = le64toh(pa);
PML4 = _kvm_malloc(kd, AMD64_PAGE_SIZE);
if (kvm_read2(kd, pa, PML4, AMD64_PAGE_SIZE) != AMD64_PAGE_SIZE) {
_kvm_err(kd, kd->program, "cannot read KPML4phys");
return (-1);
}
kd->vmst->PML4 = PML4;
return (0);
}
static int
_amd64_vatop(kvm_t *kd, kvaddr_t va, off_t *pa)
{
struct vmstate *vm;
amd64_physaddr_t offset;
amd64_physaddr_t pdpe_pa;
amd64_physaddr_t pde_pa;
amd64_physaddr_t pte_pa;
amd64_pml4e_t pml4e;
amd64_pdpe_t pdpe;
amd64_pde_t pde;
amd64_pte_t pte;
kvaddr_t pml4eindex;
kvaddr_t pdpeindex;
kvaddr_t pdeindex;
kvaddr_t pteindex;
amd64_physaddr_t a;
off_t ofs;
size_t s;
vm = kd->vmst;
offset = va & AMD64_PAGE_MASK;
/*
* If we are initializing (kernel page table descriptor pointer
* not yet set) then return pa == va to avoid infinite recursion.
*/
if (vm->PML4 == 0) {
s = _kvm_pa2off(kd, va, pa);
if (s == 0) {
_kvm_err(kd, kd->program,
"_amd64_vatop: bootstrap data not in dump");
goto invalid;
} else
return (AMD64_PAGE_SIZE - offset);
}
pml4eindex = (va >> AMD64_PML4SHIFT) & (AMD64_NPML4EPG - 1);
pml4e = le64toh(vm->PML4[pml4eindex]);
if ((pml4e & AMD64_PG_V) == 0) {
_kvm_err(kd, kd->program, "_amd64_vatop: pml4e not valid");
goto invalid;
}
pdpeindex = (va >> AMD64_PDPSHIFT) & (AMD64_NPDPEPG - 1);
pdpe_pa = (pml4e & AMD64_PG_FRAME) + (pdpeindex * sizeof(amd64_pdpe_t));
s = _kvm_pa2off(kd, pdpe_pa, &ofs);
if (s < sizeof(pdpe)) {
_kvm_err(kd, kd->program, "_amd64_vatop: pdpe_pa not found");
goto invalid;
}
if (pread(kd->pmfd, &pdpe, sizeof(pdpe), ofs) != sizeof(pdpe)) {
_kvm_syserr(kd, kd->program, "_amd64_vatop: read pdpe");
goto invalid;
}
pdpe = le64toh(pdpe);
if ((pdpe & AMD64_PG_V) == 0) {
_kvm_err(kd, kd->program, "_amd64_vatop: pdpe not valid");
goto invalid;
}
if (pdpe & AMD64_PG_PS) {
/*
* No next-level page table; pdpe describes one 1GB page.
*/
a = (pdpe & AMD64_PG_1GB_FRAME) + (va & AMD64_PDPMASK);
s = _kvm_pa2off(kd, a, pa);
if (s == 0) {
_kvm_err(kd, kd->program,
"_amd64_vatop: 1GB page address not in dump");
goto invalid;
} else
return (AMD64_NBPDP - (va & AMD64_PDPMASK));
}
pdeindex = (va >> AMD64_PDRSHIFT) & (AMD64_NPDEPG - 1);
pde_pa = (pdpe & AMD64_PG_FRAME) + (pdeindex * sizeof(amd64_pde_t));
s = _kvm_pa2off(kd, pde_pa, &ofs);
if (s < sizeof(pde)) {
_kvm_syserr(kd, kd->program, "_amd64_vatop: pde_pa not found");
goto invalid;
}
if (pread(kd->pmfd, &pde, sizeof(pde), ofs) != sizeof(pde)) {
_kvm_syserr(kd, kd->program, "_amd64_vatop: read pde");
goto invalid;
}
pde = le64toh(pde);
if ((pde & AMD64_PG_V) == 0) {
_kvm_err(kd, kd->program, "_amd64_vatop: pde not valid");
goto invalid;
}
if (pde & AMD64_PG_PS) {
/*
* No final-level page table; pde describes one 2MB page.
*/
a = (pde & AMD64_PG_PS_FRAME) + (va & AMD64_PDRMASK);
s = _kvm_pa2off(kd, a, pa);
if (s == 0) {
_kvm_err(kd, kd->program,
"_amd64_vatop: 2MB page address not in dump");
goto invalid;
} else
return (AMD64_NBPDR - (va & AMD64_PDRMASK));
}
pteindex = (va >> AMD64_PAGE_SHIFT) & (AMD64_NPTEPG - 1);
pte_pa = (pde & AMD64_PG_FRAME) + (pteindex * sizeof(amd64_pte_t));
s = _kvm_pa2off(kd, pte_pa, &ofs);
if (s < sizeof(pte)) {
_kvm_err(kd, kd->program, "_amd64_vatop: pte_pa not found");
goto invalid;
}
if (pread(kd->pmfd, &pte, sizeof(pte), ofs) != sizeof(pte)) {
_kvm_syserr(kd, kd->program, "_amd64_vatop: read");
goto invalid;
}
if ((pte & AMD64_PG_V) == 0) {
_kvm_err(kd, kd->program, "_amd64_vatop: pte not valid");
goto invalid;
}
a = (pte & AMD64_PG_FRAME) + offset;
s = _kvm_pa2off(kd, a, pa);
if (s == 0) {
_kvm_err(kd, kd->program, "_amd64_vatop: address not in dump");
goto invalid;
} else
return (AMD64_PAGE_SIZE - offset);
invalid:
_kvm_err(kd, 0, "invalid address (0x%jx)", (uintmax_t)va);
return (0);
}
static int
_amd64_kvatop(kvm_t *kd, kvaddr_t va, off_t *pa)
{
if (ISALIVE(kd)) {
_kvm_err(kd, 0, "kvm_kvatop called in live kernel!");
return (0);
}
return (_amd64_vatop(kd, va, pa));
}
int
_amd64_native(kvm_t *kd)
{
#ifdef __amd64__
return (1);
#else
return (0);
#endif
}
struct kvm_arch kvm_amd64 = {
.ka_probe = _amd64_probe,
.ka_initvtop = _amd64_initvtop,
.ka_freevtop = _amd64_freevtop,
.ka_kvatop = _amd64_kvatop,
.ka_native = _amd64_native,
};
KVM_ARCH(kvm_amd64);