HardenedBSD/lib/libkvm/kvm_minidump_powerpc64.c
D Scott Phillips 00e6614750 Sparsify the vm_page_dump bitmap
On Ampere Altra systems, the sparse population of RAM within the
physical address space causes the vm_page_dump bitmap to be much
larger than necessary, increasing the size from ~8 Mib to > 2 Gib
(and overflowing `int` for the size).

Changing the page dump bitmap also changes the minidump file
format, so changes are also necessary in libkvm.

Reviewed by:	jhb
Approved by:	scottl (implicit)
MFC after:	1 week
Sponsored by:	Ampere Computing, Inc.
Differential Revision:	https://reviews.freebsd.org/D26131
2020-09-21 22:21:59 +00:00

214 lines
6.4 KiB
C

/*-
* Copyright (c) 2006 Peter Wemm
* Copyright (c) 2019 Leandro Lupori
*
* 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.
*
* From: FreeBSD: src/lib/libkvm/kvm_minidump_riscv.c
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <kvm.h>
#include <limits.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "../../sys/powerpc/include/minidump.h"
#include "kvm_private.h"
#include "kvm_powerpc64.h"
static int
_powerpc64_minidump_probe(kvm_t *kd)
{
return (_kvm_probe_elf_kernel(kd, ELFCLASS64, EM_PPC64) &&
_kvm_is_minidump(kd));
}
static void
_powerpc64_minidump_freevtop(kvm_t *kd)
{
struct vmstate *vm = kd->vmst;
if (vm == NULL)
return;
if (PPC64_MMU_OPS(kd))
PPC64_MMU_OP(kd, cleanup);
free(vm);
kd->vmst = NULL;
}
static int
_powerpc64_minidump_initvtop(kvm_t *kd)
{
struct vmstate *vmst;
struct minidumphdr *hdr;
off_t dump_avail_off, bitmap_off, pmap_off, sparse_off;
const char *mmu_name;
/* Alloc VM */
vmst = _kvm_malloc(kd, sizeof(*vmst));
if (vmst == NULL) {
_kvm_err(kd, kd->program, "cannot allocate vm");
return (-1);
}
hdr = &vmst->hdr;
kd->vmst = vmst;
PPC64_MMU_OPS(kd) = NULL;
/* Read minidump header */
if (pread(kd->pmfd, hdr, sizeof(*hdr), 0) != sizeof(*hdr)) {
_kvm_err(kd, kd->program, "cannot read minidump header");
goto failed;
}
/* Check magic */
if (strncmp(MINIDUMP_MAGIC, hdr->magic, sizeof(hdr->magic)) != 0) {
_kvm_err(kd, kd->program, "not a minidump for this platform");
goto failed;
}
/* Check version */
hdr->version = be32toh(hdr->version);
if (hdr->version != MINIDUMP_VERSION && hdr->version != 1) {
_kvm_err(kd, kd->program, "wrong minidump version. "
"Expected %d got %d", MINIDUMP_VERSION, hdr->version);
goto failed;
}
/* Convert header fields to host endian */
hdr->msgbufsize = be32toh(hdr->msgbufsize);
hdr->bitmapsize = be32toh(hdr->bitmapsize);
hdr->pmapsize = be32toh(hdr->pmapsize);
hdr->kernbase = be64toh(hdr->kernbase);
hdr->kernend = be64toh(hdr->kernend);
hdr->dmapbase = be64toh(hdr->dmapbase);
hdr->dmapend = be64toh(hdr->dmapend);
hdr->hw_direct_map = be32toh(hdr->hw_direct_map);
hdr->startkernel = be64toh(hdr->startkernel);
hdr->endkernel = be64toh(hdr->endkernel);
hdr->dumpavailsize = hdr->version == MINIDUMP_VERSION ?
be32toh(hdr->dumpavailsize) : 0;
vmst->kimg_start = PPC64_KERNBASE;
vmst->kimg_end = PPC64_KERNBASE + hdr->endkernel - hdr->startkernel;
/* dump header */
dprintf("%s: mmu_name=%s,\n\t"
"msgbufsize=0x%jx, bitmapsize=0x%jx, pmapsize=0x%jx, "
"kernbase=0x%jx, kernend=0x%jx,\n\t"
"dmapbase=0x%jx, dmapend=0x%jx, hw_direct_map=%d, "
"startkernel=0x%jx, endkernel=0x%jx\n\t"
"kimg_start=0x%jx, kimg_end=0x%jx\n",
__func__, hdr->mmu_name,
(uintmax_t)hdr->msgbufsize,
(uintmax_t)hdr->bitmapsize, (uintmax_t)hdr->pmapsize,
(uintmax_t)hdr->kernbase, (uintmax_t)hdr->kernend,
(uintmax_t)hdr->dmapbase, (uintmax_t)hdr->dmapend,
hdr->hw_direct_map, hdr->startkernel, hdr->endkernel,
(uintmax_t)vmst->kimg_start, (uintmax_t)vmst->kimg_end);
/* Detect and initialize MMU */
mmu_name = hdr->mmu_name;
if (strcmp(mmu_name, PPC64_MMU_G5) == 0 ||
strcmp(mmu_name, PPC64_MMU_PHYP) == 0)
PPC64_MMU_OPS(kd) = ppc64_mmu_ops_hpt;
else {
_kvm_err(kd, kd->program, "unsupported MMU: %s", mmu_name);
goto failed;
}
if (PPC64_MMU_OP(kd, init) == -1)
goto failed;
/* Get dump parts' offsets */
dump_avail_off = PPC64_PAGE_SIZE + ppc64_round_page(hdr->msgbufsize);
bitmap_off = dump_avail_off + ppc64_round_page(hdr->dumpavailsize);
pmap_off = bitmap_off + ppc64_round_page(hdr->bitmapsize);
sparse_off = pmap_off + ppc64_round_page(hdr->pmapsize);
/* dump offsets */
dprintf("%s: msgbuf_off=0x%jx, bitmap_off=0x%jx, pmap_off=0x%jx, "
"sparse_off=0x%jx\n",
__func__, (uintmax_t)PPC64_PAGE_SIZE, (uintmax_t)bitmap_off,
(uintmax_t)pmap_off, (uintmax_t)sparse_off);
/* build physical address lookup table for sparse pages */
if (_kvm_pt_init(kd, hdr->dumpavailsize, dump_avail_off,
hdr->bitmapsize, bitmap_off, sparse_off, PPC64_PAGE_SIZE,
sizeof(uint64_t)) == -1)
goto failed;
if (_kvm_pmap_init(kd, hdr->pmapsize, pmap_off) == -1)
goto failed;
return (0);
failed:
_powerpc64_minidump_freevtop(kd);
return (-1);
}
static int
_powerpc64_minidump_kvatop(kvm_t *kd, kvaddr_t va, off_t *pa)
{
if (ISALIVE(kd)) {
_kvm_err(kd, 0, "%s called in live kernel!", __func__);
return (0);
}
return (PPC64_MMU_OP(kd, kvatop, va, pa));
}
static int
_powerpc64_native(kvm_t *kd __unused)
{
#ifdef __powerpc64__
return (1);
#else
return (0);
#endif
}
static kssize_t
_powerpc64_kerndisp(kvm_t *kd)
{
return (kd->vmst->hdr.startkernel - PPC64_KERNBASE);
}
static int
_powerpc64_minidump_walk_pages(kvm_t *kd, kvm_walk_pages_cb_t *cb, void *arg)
{
return (PPC64_MMU_OP(kd, walk_pages, cb, arg));
}
static struct kvm_arch kvm_powerpc64_minidump = {
.ka_probe = _powerpc64_minidump_probe,
.ka_initvtop = _powerpc64_minidump_initvtop,
.ka_freevtop = _powerpc64_minidump_freevtop,
.ka_kvatop = _powerpc64_minidump_kvatop,
.ka_walk_pages = _powerpc64_minidump_walk_pages,
.ka_native = _powerpc64_native,
.ka_kerndisp = _powerpc64_kerndisp,
};
KVM_ARCH(kvm_powerpc64_minidump);