qemu-e2k/hw/openrisc/openrisc_sim.c
Markus Armbruster f8ed85ac99 Fix bad error handling after memory_region_init_ram()
Symptom:

    $ qemu-system-x86_64 -m 10000000
    Unexpected error in ram_block_add() at /work/armbru/qemu/exec.c:1456:
    upstream-qemu: cannot set up guest memory 'pc.ram': Cannot allocate memory
    Aborted (core dumped)

Root cause: commit ef701d7 screwed up handling of out-of-memory
conditions.  Before the commit, we report the error and exit(1), in
one place, ram_block_add().  The commit lifts the error handling up
the call chain some, to three places.  Fine.  Except it uses
&error_abort in these places, changing the behavior from exit(1) to
abort(), and thus undoing the work of commit 3922825 "exec: Don't
abort when we can't allocate guest memory".

The three places are:

* memory_region_init_ram()

  Commit 4994653 (right after commit ef701d7) lifted the error
  handling further, through memory_region_init_ram(), multiplying the
  incorrect use of &error_abort.  Later on, imitation of existing
  (bad) code may have created more.

* memory_region_init_ram_ptr()

  The &error_abort is still there.

* memory_region_init_rom_device()

  Doesn't need fixing, because commit 33e0eb5 (soon after commit
  ef701d7) lifted the error handling further, and in the process
  changed it from &error_abort to passing it up the call chain.
  Correct, because the callers are realize() methods.

Fix the error handling after memory_region_init_ram() with a
Coccinelle semantic patch:

    @r@
    expression mr, owner, name, size, err;
    position p;
    @@
            memory_region_init_ram(mr, owner, name, size,
    (
    -                              &error_abort
    +                              &error_fatal
    |
                                   err@p
    )
                                  );
    @script:python@
        p << r.p;
    @@
    print "%s:%s:%s" % (p[0].file, p[0].line, p[0].column)

When the last argument is &error_abort, it gets replaced by
&error_fatal.  This is the fix.

If the last argument is anything else, its position is reported.  This
lets us check the fix is complete.  Four positions get reported:

* ram_backend_memory_alloc()

  Error is passed up the call chain, ultimately through
  user_creatable_complete().  As far as I can tell, it's callers all
  handle the error sanely.

* fsl_imx25_realize(), fsl_imx31_realize(), dp8393x_realize()

  DeviceClass.realize() methods, errors handled sanely further up the
  call chain.

We're good.  Test case again behaves:

    $ qemu-system-x86_64 -m 10000000
    qemu-system-x86_64: cannot set up guest memory 'pc.ram': Cannot allocate memory
    [Exit 1 ]

The next commits will repair the rest of commit ef701d7's damage.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1441983105-26376-3-git-send-email-armbru@redhat.com>
Reviewed-by: Peter Crosthwaite <crosthwaite.peter@gmail.com>
2015-09-18 14:39:29 +02:00

149 lines
4.5 KiB
C

/*
* OpenRISC simulator for use as an IIS.
*
* Copyright (c) 2011-2012 Jia Liu <proljc@gmail.com>
* Feng Gao <gf91597@gmail.com>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, see <http://www.gnu.org/licenses/>.
*/
#include "hw/hw.h"
#include "hw/boards.h"
#include "elf.h"
#include "hw/char/serial.h"
#include "net/net.h"
#include "hw/loader.h"
#include "exec/address-spaces.h"
#include "sysemu/sysemu.h"
#include "hw/sysbus.h"
#include "sysemu/qtest.h"
#define KERNEL_LOAD_ADDR 0x100
static void main_cpu_reset(void *opaque)
{
OpenRISCCPU *cpu = opaque;
cpu_reset(CPU(cpu));
}
static void openrisc_sim_net_init(MemoryRegion *address_space,
hwaddr base,
hwaddr descriptors,
qemu_irq irq, NICInfo *nd)
{
DeviceState *dev;
SysBusDevice *s;
dev = qdev_create(NULL, "open_eth");
qdev_set_nic_properties(dev, nd);
qdev_init_nofail(dev);
s = SYS_BUS_DEVICE(dev);
sysbus_connect_irq(s, 0, irq);
memory_region_add_subregion(address_space, base,
sysbus_mmio_get_region(s, 0));
memory_region_add_subregion(address_space, descriptors,
sysbus_mmio_get_region(s, 1));
}
static void cpu_openrisc_load_kernel(ram_addr_t ram_size,
const char *kernel_filename,
OpenRISCCPU *cpu)
{
long kernel_size;
uint64_t elf_entry;
hwaddr entry;
if (kernel_filename && !qtest_enabled()) {
kernel_size = load_elf(kernel_filename, NULL, NULL,
&elf_entry, NULL, NULL, 1, ELF_MACHINE, 1);
entry = elf_entry;
if (kernel_size < 0) {
kernel_size = load_uimage(kernel_filename,
&entry, NULL, NULL, NULL, NULL);
}
if (kernel_size < 0) {
kernel_size = load_image_targphys(kernel_filename,
KERNEL_LOAD_ADDR,
ram_size - KERNEL_LOAD_ADDR);
entry = KERNEL_LOAD_ADDR;
}
if (kernel_size < 0) {
fprintf(stderr, "QEMU: couldn't load the kernel '%s'\n",
kernel_filename);
exit(1);
}
cpu->env.pc = entry;
}
}
static void openrisc_sim_init(MachineState *machine)
{
ram_addr_t ram_size = machine->ram_size;
const char *cpu_model = machine->cpu_model;
const char *kernel_filename = machine->kernel_filename;
OpenRISCCPU *cpu = NULL;
MemoryRegion *ram;
int n;
if (!cpu_model) {
cpu_model = "or1200";
}
for (n = 0; n < smp_cpus; n++) {
cpu = cpu_openrisc_init(cpu_model);
if (cpu == NULL) {
fprintf(stderr, "Unable to find CPU definition!\n");
exit(1);
}
qemu_register_reset(main_cpu_reset, cpu);
main_cpu_reset(cpu);
}
ram = g_malloc(sizeof(*ram));
memory_region_init_ram(ram, NULL, "openrisc.ram", ram_size, &error_fatal);
vmstate_register_ram_global(ram);
memory_region_add_subregion(get_system_memory(), 0, ram);
cpu_openrisc_pic_init(cpu);
cpu_openrisc_clock_init(cpu);
serial_mm_init(get_system_memory(), 0x90000000, 0, cpu->env.irq[2],
115200, serial_hds[0], DEVICE_NATIVE_ENDIAN);
if (nd_table[0].used) {
openrisc_sim_net_init(get_system_memory(), 0x92000000,
0x92000400, cpu->env.irq[4], nd_table);
}
cpu_openrisc_load_kernel(ram_size, kernel_filename, cpu);
}
static QEMUMachine openrisc_sim_machine = {
.name = "or32-sim",
.desc = "or32 simulation",
.init = openrisc_sim_init,
.max_cpus = 1,
.is_default = 1,
};
static void openrisc_sim_machine_init(void)
{
qemu_register_machine(&openrisc_sim_machine);
}
machine_init(openrisc_sim_machine_init);