qemu-patch-raspberry4/hw/m68k/an5206.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

104 lines
2.8 KiB
C

/*
* Arnewsh 5206 ColdFire system emulation.
*
* Copyright (c) 2007 CodeSourcery.
*
* This code is licensed under the GPL
*/
#include "hw/hw.h"
#include "hw/m68k/mcf.h"
#include "hw/boards.h"
#include "hw/loader.h"
#include "elf.h"
#include "exec/address-spaces.h"
#include "sysemu/qtest.h"
#define KERNEL_LOAD_ADDR 0x10000
#define AN5206_MBAR_ADDR 0x10000000
#define AN5206_RAMBAR_ADDR 0x20000000
/* Board init. */
static void an5206_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;
M68kCPU *cpu;
CPUM68KState *env;
int kernel_size;
uint64_t elf_entry;
hwaddr entry;
MemoryRegion *address_space_mem = get_system_memory();
MemoryRegion *ram = g_new(MemoryRegion, 1);
MemoryRegion *sram = g_new(MemoryRegion, 1);
if (!cpu_model) {
cpu_model = "m5206";
}
cpu = cpu_m68k_init(cpu_model);
if (!cpu) {
hw_error("Unable to find m68k CPU definition\n");
}
env = &cpu->env;
/* Initialize CPU registers. */
env->vbr = 0;
/* TODO: allow changing MBAR and RAMBAR. */
env->mbar = AN5206_MBAR_ADDR | 1;
env->rambar0 = AN5206_RAMBAR_ADDR | 1;
/* DRAM at address zero */
memory_region_allocate_system_memory(ram, NULL, "an5206.ram", ram_size);
memory_region_add_subregion(address_space_mem, 0, ram);
/* Internal SRAM. */
memory_region_init_ram(sram, NULL, "an5206.sram", 512, &error_fatal);
vmstate_register_ram_global(sram);
memory_region_add_subregion(address_space_mem, AN5206_RAMBAR_ADDR, sram);
mcf5206_init(address_space_mem, AN5206_MBAR_ADDR, cpu);
/* Load kernel. */
if (!kernel_filename) {
if (qtest_enabled()) {
return;
}
fprintf(stderr, "Kernel image must be specified\n");
exit(1);
}
kernel_size = load_elf(kernel_filename, NULL, NULL, &elf_entry,
NULL, NULL, 1, ELF_MACHINE, 0);
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: could not load kernel '%s'\n", kernel_filename);
exit(1);
}
env->pc = entry;
}
static QEMUMachine an5206_machine = {
.name = "an5206",
.desc = "Arnewsh 5206",
.init = an5206_init,
};
static void an5206_machine_init(void)
{
qemu_register_machine(&an5206_machine);
}
machine_init(an5206_machine_init);