aboutsummaryrefslogtreecommitdiff
path: root/hw/input
diff options
context:
space:
mode:
authorMarkus Armbruster <armbru@redhat.com>2015-09-11 16:51:43 +0200
committerMarkus Armbruster <armbru@redhat.com>2015-09-18 14:39:29 +0200
commitf8ed85ac992c48814d916d5df4d44f9a971c5de4 (patch)
tree125b3e69a5c5393cb0db622f7c3a7f1893f9f9ea /hw/input
parenta29a37b994ca3c5a1d39fa0e8934f7e0f2cf57ef (diff)
downloadqemu-f8ed85ac992c48814d916d5df4d44f9a971c5de4.zip
qemu-f8ed85ac992c48814d916d5df4d44f9a971c5de4.tar.gz
qemu-f8ed85ac992c48814d916d5df4d44f9a971c5de4.tar.bz2
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>
Diffstat (limited to 'hw/input')
-rw-r--r--hw/input/milkymist-softusb.c4
1 files changed, 2 insertions, 2 deletions
diff --git a/hw/input/milkymist-softusb.c b/hw/input/milkymist-softusb.c
index 7b0f4db..8a02d35 100644
--- a/hw/input/milkymist-softusb.c
+++ b/hw/input/milkymist-softusb.c
@@ -255,12 +255,12 @@ static int milkymist_softusb_init(SysBusDevice *dev)
/* register pmem and dmem */
memory_region_init_ram(&s->pmem, OBJECT(s), "milkymist-softusb.pmem",
- s->pmem_size, &error_abort);
+ s->pmem_size, &error_fatal);
vmstate_register_ram_global(&s->pmem);
s->pmem_ptr = memory_region_get_ram_ptr(&s->pmem);
sysbus_init_mmio(dev, &s->pmem);
memory_region_init_ram(&s->dmem, OBJECT(s), "milkymist-softusb.dmem",
- s->dmem_size, &error_abort);
+ s->dmem_size, &error_fatal);
vmstate_register_ram_global(&s->dmem);
s->dmem_ptr = memory_region_get_ram_ptr(&s->dmem);
sysbus_init_mmio(dev, &s->dmem);