aboutsummaryrefslogtreecommitdiff
path: root/lib/libkvm/kvm_minidump_amd64.c
diff options
context:
space:
mode:
Diffstat (limited to 'lib/libkvm/kvm_minidump_amd64.c')
-rw-r--r--lib/libkvm/kvm_minidump_amd64.c440
1 files changed, 440 insertions, 0 deletions
diff --git a/lib/libkvm/kvm_minidump_amd64.c b/lib/libkvm/kvm_minidump_amd64.c
new file mode 100644
index 000000000000..e121208a628a
--- /dev/null
+++ b/lib/libkvm/kvm_minidump_amd64.c
@@ -0,0 +1,440 @@
+/*-
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Copyright (c) 2006 Peter Wemm
+ *
+ * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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>
+/*
+ * AMD64 machine dependent routines for kvm and minidumps.
+ */
+
+#include <sys/param.h>
+#include <sys/endian.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <vm/vm.h>
+#include <kvm.h>
+
+#include "../../sys/amd64/include/minidump.h"
+
+#include <limits.h>
+
+#include "kvm_private.h"
+#include "kvm_amd64.h"
+
+#define amd64_round_page(x) roundup2((kvaddr_t)(x), AMD64_PAGE_SIZE)
+#define VM_IS_V1(vm) (vm->hdr.version == 1)
+#define VA_OFF(vm, va) \
+ (VM_IS_V1(vm) ? ((va) & (AMD64_PAGE_SIZE - 1)) : ((va) & AMD64_PAGE_MASK))
+
+struct vmstate {
+ struct minidumphdr hdr;
+};
+
+static vm_prot_t
+_amd64_entry_to_prot(uint64_t entry)
+{
+ vm_prot_t prot = VM_PROT_READ;
+
+ if ((entry & AMD64_PG_RW) != 0)
+ prot |= VM_PROT_WRITE;
+ if ((entry & AMD64_PG_NX) == 0)
+ prot |= VM_PROT_EXECUTE;
+ return prot;
+}
+
+/*
+ * Version 2 minidumps use page directory entries, while version 1 use page
+ * table entries.
+ */
+
+static amd64_pde_t
+_amd64_pde_get(kvm_t *kd, u_long pdeindex)
+{
+ amd64_pde_t *pde = _kvm_pmap_get(kd, pdeindex, sizeof(*pde));
+
+ return le64toh(*pde);
+}
+
+static amd64_pte_t
+_amd64_pte_get(kvm_t *kd, u_long pteindex)
+{
+ amd64_pte_t *pte = _kvm_pmap_get(kd, pteindex, sizeof(*pte));
+
+ return le64toh(*pte);
+}
+
+/* Get the first page table entry for a given page directory index. */
+static amd64_pte_t *
+_amd64_pde_first_pte(kvm_t *kd, u_long pdeindex)
+{
+ u_long *pa;
+
+ pa = _kvm_pmap_get(kd, pdeindex, sizeof(amd64_pde_t));
+ if (pa == NULL)
+ return NULL;
+ return _kvm_map_get(kd, *pa & AMD64_PG_FRAME, AMD64_PAGE_SIZE);
+}
+
+static int
+_amd64_minidump_probe(kvm_t *kd)
+{
+
+ return (_kvm_probe_elf_kernel(kd, ELFCLASS64, EM_X86_64) &&
+ _kvm_is_minidump(kd));
+}
+
+static void
+_amd64_minidump_freevtop(kvm_t *kd)
+{
+ struct vmstate *vm = kd->vmst;
+
+ free(vm);
+ kd->vmst = NULL;
+}
+
+static int
+_amd64_minidump_initvtop(kvm_t *kd)
+{
+ struct vmstate *vmst;
+ off_t off, dump_avail_off, sparse_off;
+
+ vmst = _kvm_malloc(kd, sizeof(*vmst));
+ if (vmst == NULL) {
+ _kvm_err(kd, kd->program, "cannot allocate vm");
+ return (-1);
+ }
+ kd->vmst = vmst;
+ if (pread(kd->pmfd, &vmst->hdr, sizeof(vmst->hdr), 0) !=
+ sizeof(vmst->hdr)) {
+ _kvm_err(kd, kd->program, "cannot read dump header");
+ return (-1);
+ }
+ if (strncmp(MINIDUMP_MAGIC, vmst->hdr.magic, sizeof(vmst->hdr.magic)) != 0) {
+ _kvm_err(kd, kd->program, "not a minidump for this platform");
+ return (-1);
+ }
+
+ /*
+ * NB: amd64 minidump header is binary compatible between version 1
+ * and version 2; version 3 adds the dumpavailsize field
+ */
+ vmst->hdr.version = le32toh(vmst->hdr.version);
+ if (vmst->hdr.version > MINIDUMP_VERSION || vmst->hdr.version < 1) {
+ _kvm_err(kd, kd->program, "wrong minidump version. expected %d got %d",
+ MINIDUMP_VERSION, vmst->hdr.version);
+ return (-1);
+ }
+ vmst->hdr.msgbufsize = le32toh(vmst->hdr.msgbufsize);
+ vmst->hdr.bitmapsize = le32toh(vmst->hdr.bitmapsize);
+ vmst->hdr.pmapsize = le32toh(vmst->hdr.pmapsize);
+ vmst->hdr.kernbase = le64toh(vmst->hdr.kernbase);
+ vmst->hdr.dmapbase = le64toh(vmst->hdr.dmapbase);
+ vmst->hdr.dmapend = le64toh(vmst->hdr.dmapend);
+ vmst->hdr.dumpavailsize = vmst->hdr.version == MINIDUMP_VERSION ?
+ le32toh(vmst->hdr.dumpavailsize) : 0;
+
+ /* Skip header and msgbuf */
+ dump_avail_off = AMD64_PAGE_SIZE + amd64_round_page(vmst->hdr.msgbufsize);
+
+ /* Skip dump_avail */
+ off = dump_avail_off + amd64_round_page(vmst->hdr.dumpavailsize);
+
+ sparse_off = off + amd64_round_page(vmst->hdr.bitmapsize) +
+ amd64_round_page(vmst->hdr.pmapsize);
+ if (_kvm_pt_init(kd, vmst->hdr.dumpavailsize, dump_avail_off,
+ vmst->hdr.bitmapsize, off, sparse_off, AMD64_PAGE_SIZE) == -1) {
+ return (-1);
+ }
+ off += amd64_round_page(vmst->hdr.bitmapsize);
+
+ if (_kvm_pmap_init(kd, vmst->hdr.pmapsize, off) == -1) {
+ return (-1);
+ }
+ off += amd64_round_page(vmst->hdr.pmapsize);
+
+ return (0);
+}
+
+static int
+_amd64_minidump_vatop_v1(kvm_t *kd, kvaddr_t va, off_t *pa)
+{
+ struct vmstate *vm;
+ amd64_physaddr_t offset;
+ amd64_pte_t pte;
+ kvaddr_t pteindex;
+ amd64_physaddr_t a;
+ off_t ofs;
+
+ vm = kd->vmst;
+ offset = va & AMD64_PAGE_MASK;
+
+ if (va >= vm->hdr.kernbase) {
+ pteindex = (va - vm->hdr.kernbase) >> AMD64_PAGE_SHIFT;
+ if (pteindex >= vm->hdr.pmapsize / sizeof(pte))
+ goto invalid;
+ pte = _amd64_pte_get(kd, pteindex);
+ if ((pte & AMD64_PG_V) == 0) {
+ _kvm_err(kd, kd->program,
+ "_amd64_minidump_vatop_v1: pte not valid");
+ goto invalid;
+ }
+ a = pte & AMD64_PG_FRAME;
+ ofs = _kvm_pt_find(kd, a, AMD64_PAGE_SIZE);
+ if (ofs == -1) {
+ _kvm_err(kd, kd->program,
+ "_amd64_minidump_vatop_v1: physical address 0x%jx not in minidump",
+ (uintmax_t)a);
+ goto invalid;
+ }
+ *pa = ofs + offset;
+ return (AMD64_PAGE_SIZE - offset);
+ } else if (va >= vm->hdr.dmapbase && va < vm->hdr.dmapend) {
+ a = (va - vm->hdr.dmapbase) & ~AMD64_PAGE_MASK;
+ ofs = _kvm_pt_find(kd, a, AMD64_PAGE_SIZE);
+ if (ofs == -1) {
+ _kvm_err(kd, kd->program,
+ "_amd64_minidump_vatop_v1: direct map address 0x%jx not in minidump",
+ (uintmax_t)va);
+ goto invalid;
+ }
+ *pa = ofs + offset;
+ return (AMD64_PAGE_SIZE - offset);
+ } else {
+ _kvm_err(kd, kd->program,
+ "_amd64_minidump_vatop_v1: virtual address 0x%jx not minidumped",
+ (uintmax_t)va);
+ goto invalid;
+ }
+
+invalid:
+ _kvm_err(kd, 0, "invalid address (0x%jx)", (uintmax_t)va);
+ return (0);
+}
+
+static int
+_amd64_minidump_vatop(kvm_t *kd, kvaddr_t va, off_t *pa)
+{
+ amd64_pte_t pt[AMD64_NPTEPG];
+ struct vmstate *vm;
+ amd64_physaddr_t offset;
+ amd64_pde_t pde;
+ amd64_pte_t pte;
+ kvaddr_t pteindex;
+ kvaddr_t pdeindex;
+ amd64_physaddr_t a;
+ off_t ofs;
+
+ vm = kd->vmst;
+ offset = va & AMD64_PAGE_MASK;
+
+ if (va >= vm->hdr.kernbase) {
+ pdeindex = (va - vm->hdr.kernbase) >> AMD64_PDRSHIFT;
+ if (pdeindex >= vm->hdr.pmapsize / sizeof(pde))
+ goto invalid;
+ pde = _amd64_pde_get(kd, pdeindex);
+ if ((pde & AMD64_PG_V) == 0) {
+ _kvm_err(kd, kd->program,
+ "_amd64_minidump_vatop: pde not valid");
+ goto invalid;
+ }
+ if ((pde & AMD64_PG_PS) == 0) {
+ a = pde & AMD64_PG_FRAME;
+ /* TODO: Just read the single PTE */
+ ofs = _kvm_pt_find(kd, a, AMD64_PAGE_SIZE);
+ if (ofs == -1) {
+ _kvm_err(kd, kd->program,
+ "cannot find page table entry for %ju",
+ (uintmax_t)a);
+ goto invalid;
+ }
+ if (pread(kd->pmfd, &pt, AMD64_PAGE_SIZE, ofs) !=
+ AMD64_PAGE_SIZE) {
+ _kvm_err(kd, kd->program,
+ "cannot read page table entry for %ju",
+ (uintmax_t)a);
+ goto invalid;
+ }
+ pteindex = (va >> AMD64_PAGE_SHIFT) &
+ (AMD64_NPTEPG - 1);
+ pte = le64toh(pt[pteindex]);
+ if ((pte & AMD64_PG_V) == 0) {
+ _kvm_err(kd, kd->program,
+ "_amd64_minidump_vatop: pte not valid");
+ goto invalid;
+ }
+ a = pte & AMD64_PG_FRAME;
+ } else {
+ a = pde & AMD64_PG_PS_FRAME;
+ a += (va & AMD64_PDRMASK) ^ offset;
+ }
+ ofs = _kvm_pt_find(kd, a, AMD64_PAGE_SIZE);
+ if (ofs == -1) {
+ _kvm_err(kd, kd->program,
+ "_amd64_minidump_vatop: physical address 0x%jx not in minidump",
+ (uintmax_t)a);
+ goto invalid;
+ }
+ *pa = ofs + offset;
+ return (AMD64_PAGE_SIZE - offset);
+ } else if (va >= vm->hdr.dmapbase && va < vm->hdr.dmapend) {
+ a = (va - vm->hdr.dmapbase) & ~AMD64_PAGE_MASK;
+ ofs = _kvm_pt_find(kd, a, AMD64_PAGE_SIZE);
+ if (ofs == -1) {
+ _kvm_err(kd, kd->program,
+ "_amd64_minidump_vatop: direct map address 0x%jx not in minidump",
+ (uintmax_t)va);
+ goto invalid;
+ }
+ *pa = ofs + offset;
+ return (AMD64_PAGE_SIZE - offset);
+ } else {
+ _kvm_err(kd, kd->program,
+ "_amd64_minidump_vatop: virtual address 0x%jx not minidumped",
+ (uintmax_t)va);
+ goto invalid;
+ }
+
+invalid:
+ _kvm_err(kd, 0, "invalid address (0x%jx)", (uintmax_t)va);
+ return (0);
+}
+
+static int
+_amd64_minidump_kvatop(kvm_t *kd, kvaddr_t va, off_t *pa)
+{
+
+ if (ISALIVE(kd)) {
+ _kvm_err(kd, 0,
+ "_amd64_minidump_kvatop called in live kernel!");
+ return (0);
+ }
+ if (((struct vmstate *)kd->vmst)->hdr.version == 1)
+ return (_amd64_minidump_vatop_v1(kd, va, pa));
+ else
+ return (_amd64_minidump_vatop(kd, va, pa));
+}
+
+static int
+_amd64_minidump_walk_pages(kvm_t *kd, kvm_walk_pages_cb_t *cb, void *arg)
+{
+ struct vmstate *vm = kd->vmst;
+ u_long npdes = vm->hdr.pmapsize / sizeof(amd64_pde_t);
+ u_long bmindex, dva, pa, pdeindex, va;
+ struct kvm_bitmap bm;
+ int ret = 0;
+ vm_prot_t prot;
+ unsigned int pgsz = AMD64_PAGE_SIZE;
+
+ if (vm->hdr.version < 2)
+ return (0);
+
+ if (!_kvm_bitmap_init(&bm, vm->hdr.bitmapsize, &bmindex))
+ return (0);
+
+ for (pdeindex = 0; pdeindex < npdes; pdeindex++) {
+ amd64_pde_t pde = _amd64_pde_get(kd, pdeindex);
+ amd64_pte_t *ptes;
+ u_long i;
+
+ va = vm->hdr.kernbase + (pdeindex << AMD64_PDRSHIFT);
+ if ((pde & AMD64_PG_V) == 0)
+ continue;
+
+ if ((pde & AMD64_PG_PS) != 0) {
+ /*
+ * Large page. Iterate on each 4K page section
+ * within this page. This differs from 4K pages in
+ * that every page here uses the same PDE to
+ * generate permissions.
+ */
+ pa = (pde & AMD64_PG_PS_FRAME) +
+ ((va & AMD64_PDRMASK) ^ VA_OFF(vm, va));
+ dva = vm->hdr.dmapbase + pa;
+ _kvm_bitmap_set(&bm, _kvm_pa_bit_id(kd, pa, AMD64_PAGE_SIZE));
+ if (!_kvm_visit_cb(kd, cb, arg, pa, va, dva,
+ _amd64_entry_to_prot(pde), AMD64_NBPDR, pgsz)) {
+ goto out;
+ }
+ continue;
+ }
+
+ /* 4K pages: pde references another page of entries. */
+ ptes = _amd64_pde_first_pte(kd, pdeindex);
+ /* Ignore page directory pages that were not dumped. */
+ if (ptes == NULL)
+ continue;
+
+ for (i = 0; i < AMD64_NPTEPG; i++) {
+ amd64_pte_t pte = (u_long)ptes[i];
+
+ pa = pte & AMD64_PG_FRAME;
+ dva = vm->hdr.dmapbase + pa;
+ if ((pte & AMD64_PG_V) != 0) {
+ _kvm_bitmap_set(&bm,
+ _kvm_pa_bit_id(kd, pa, AMD64_PAGE_SIZE));
+ if (!_kvm_visit_cb(kd, cb, arg, pa, va, dva,
+ _amd64_entry_to_prot(pte), pgsz, 0)) {
+ goto out;
+ }
+ }
+ va += AMD64_PAGE_SIZE;
+ }
+ }
+
+ while (_kvm_bitmap_next(&bm, &bmindex)) {
+ pa = _kvm_bit_id_pa(kd, bmindex, AMD64_PAGE_SIZE);
+ if (pa == _KVM_PA_INVALID)
+ break;
+ dva = vm->hdr.dmapbase + pa;
+ if (vm->hdr.dmapend < (dva + pgsz))
+ break;
+ va = 0;
+ /* amd64/pmap.c: create_pagetables(): dmap always R|W. */
+ prot = VM_PROT_READ | VM_PROT_WRITE;
+ if (!_kvm_visit_cb(kd, cb, arg, pa, va, dva, prot, pgsz, 0)) {
+ goto out;
+ }
+ }
+
+ ret = 1;
+
+out:
+ _kvm_bitmap_deinit(&bm);
+ return (ret);
+}
+
+static struct kvm_arch kvm_amd64_minidump = {
+ .ka_probe = _amd64_minidump_probe,
+ .ka_initvtop = _amd64_minidump_initvtop,
+ .ka_freevtop = _amd64_minidump_freevtop,
+ .ka_kvatop = _amd64_minidump_kvatop,
+ .ka_native = _amd64_native,
+ .ka_walk_pages = _amd64_minidump_walk_pages,
+};
+
+KVM_ARCH(kvm_amd64_minidump);
generated by cgit v1.2.3 (git 2.25.1) at 2025-10-07 11:52:15 +0000