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>

7 files changed, 11 insertions, 11 deletions

diff --git a/hw/display/cg3.c b/hw/display/cg3.c
index 34dcbc3..d2a0d97 100644
--- a/hw/display/cg3.c
+++ b/hw/display/cg3.c
@@ -281,7 +281,7 @@ static void cg3_initfn(Object *obj)
     CG3State *s = CG3(obj);
 
     memory_region_init_ram(&s->rom, NULL, "cg3.prom", FCODE_MAX_ROM_SIZE,
-                           &error_abort);
+                           &error_fatal);
     memory_region_set_readonly(&s->rom, true);
     sysbus_init_mmio(sbd, &s->rom);
 
@@ -310,7 +310,7 @@ static void cg3_realizefn(DeviceState *dev, Error **errp)
     }
 
     memory_region_init_ram(&s->vram_mem, NULL, "cg3.vram", s->vram_size,
-                           &error_abort);
+                           &error_fatal);
     memory_region_set_log(&s->vram_mem, true, DIRTY_MEMORY_VGA);
     vmstate_register_ram_global(&s->vram_mem);
     sysbus_init_mmio(sbd, &s->vram_mem);
diff --git a/hw/display/qxl.c b/hw/display/qxl.c
index 2288238..9c961da 100644
--- a/hw/display/qxl.c
+++ b/hw/display/qxl.c
@@ -1970,14 +1970,14 @@ static void qxl_realize_common(PCIQXLDevice *qxl, Error **errp)
 
     qxl->rom_size = qxl_rom_size();
     memory_region_init_ram(&qxl->rom_bar, OBJECT(qxl), "qxl.vrom",
-                           qxl->rom_size, &error_abort);
+                           qxl->rom_size, &error_fatal);
     vmstate_register_ram(&qxl->rom_bar, &qxl->pci.qdev);
     init_qxl_rom(qxl);
     init_qxl_ram(qxl);
 
     qxl->guest_surfaces.cmds = g_new0(QXLPHYSICAL, qxl->ssd.num_surfaces);
     memory_region_init_ram(&qxl->vram_bar, OBJECT(qxl), "qxl.vram",
-                           qxl->vram_size, &error_abort);
+                           qxl->vram_size, &error_fatal);
     vmstate_register_ram(&qxl->vram_bar, &qxl->pci.qdev);
     memory_region_init_alias(&qxl->vram32_bar, OBJECT(qxl), "qxl.vram32",
                              &qxl->vram_bar, 0, qxl->vram32_size);
@@ -2079,7 +2079,7 @@ static void qxl_realize_secondary(PCIDevice *dev, Error **errp)
     qxl->id = device_id++;
     qxl_init_ramsize(qxl);
     memory_region_init_ram(&qxl->vga.vram, OBJECT(dev), "qxl.vgavram",
-                           qxl->vga.vram_size, &error_abort);
+                           qxl->vga.vram_size, &error_fatal);
     vmstate_register_ram(&qxl->vga.vram, &qxl->pci.qdev);
     qxl->vga.vram_ptr = memory_region_get_ram_ptr(&qxl->vga.vram);
     qxl->vga.con = graphic_console_init(DEVICE(dev), 0, &qxl_ops, qxl);
diff --git a/hw/display/sm501.c b/hw/display/sm501.c
index 15a5ba8..3c3f978 100644
--- a/hw/display/sm501.c
+++ b/hw/display/sm501.c
@@ -1411,7 +1411,7 @@ void sm501_init(MemoryRegion *address_space_mem, uint32_t base,
 
     /* allocate local memory */
     memory_region_init_ram(&s->local_mem_region, NULL, "sm501.local",
-                           local_mem_bytes, &error_abort);
+                           local_mem_bytes, &error_fatal);
     vmstate_register_ram_global(&s->local_mem_region);
     memory_region_set_log(&s->local_mem_region, true, DIRTY_MEMORY_VGA);
     s->local_mem = memory_region_get_ram_ptr(&s->local_mem_region);
diff --git a/hw/display/tc6393xb.c b/hw/display/tc6393xb.c
index f5f3f3e..516af1a 100644
--- a/hw/display/tc6393xb.c
+++ b/hw/display/tc6393xb.c
@@ -584,7 +584,7 @@ TC6393xbState *tc6393xb_init(MemoryRegion *sysmem, uint32_t base, qemu_irq irq)
     memory_region_add_subregion(sysmem, base, &s->iomem);
 
     memory_region_init_ram(&s->vram, NULL, "tc6393xb.vram", 0x100000,
-                           &error_abort);
+                           &error_fatal);
     vmstate_register_ram_global(&s->vram);
     s->vram_ptr = memory_region_get_ram_ptr(&s->vram);
     memory_region_add_subregion(sysmem, base + 0x100000, &s->vram);
diff --git a/hw/display/tcx.c b/hw/display/tcx.c
index 6acdc2d..4635800 100644
--- a/hw/display/tcx.c
+++ b/hw/display/tcx.c
@@ -945,7 +945,7 @@ static void tcx_initfn(Object *obj)
     TCXState *s = TCX(obj);
 
     memory_region_init_ram(&s->rom, NULL, "tcx.prom", FCODE_MAX_ROM_SIZE,
-                           &error_abort);
+                           &error_fatal);
     memory_region_set_readonly(&s->rom, true);
     sysbus_init_mmio(sbd, &s->rom);
 
@@ -1007,7 +1007,7 @@ static void tcx_realizefn(DeviceState *dev, Error **errp)
     char *fcode_filename;
 
     memory_region_init_ram(&s->vram_mem, OBJECT(s), "tcx.vram",
-                           s->vram_size * (1 + 4 + 4), &error_abort);
+                           s->vram_size * (1 + 4 + 4), &error_fatal);
     vmstate_register_ram_global(&s->vram_mem);
     memory_region_set_log(&s->vram_mem, true, DIRTY_MEMORY_VGA);
     vram_base = memory_region_get_ram_ptr(&s->vram_mem);
diff --git a/hw/display/vga.c b/hw/display/vga.c
index b35d523..9f68394 100644
--- a/hw/display/vga.c
+++ b/hw/display/vga.c
@@ -2139,7 +2139,7 @@ void vga_common_init(VGACommonState *s, Object *obj, bool global_vmstate)
 
     s->is_vbe_vmstate = 1;
     memory_region_init_ram(&s->vram, obj, "vga.vram", s->vram_size,
-                           &error_abort);
+                           &error_fatal);
     vmstate_register_ram(&s->vram, global_vmstate ? NULL : DEVICE(obj));
     xen_register_framebuffer(&s->vram);
     s->vram_ptr = memory_region_get_ram_ptr(&s->vram);
diff --git a/hw/display/vmware_vga.c b/hw/display/vmware_vga.c
index 7f397d3..8e93509 100644
--- a/hw/display/vmware_vga.c
+++ b/hw/display/vmware_vga.c
@@ -1244,7 +1244,7 @@ static void vmsvga_init(DeviceState *dev, struct vmsvga_state_s *s,
 
     s->fifo_size = SVGA_FIFO_SIZE;
     memory_region_init_ram(&s->fifo_ram, NULL, "vmsvga.fifo", s->fifo_size,
-                           &error_abort);
+                           &error_fatal);
     vmstate_register_ram_global(&s->fifo_ram);
     s->fifo_ptr = memory_region_get_ram_ptr(&s->fifo_ram);