This breaks qemu-io test for me.
#0 0x000003ff98f3e2d4 in raise () at /lib64/libc.so.6
#1 0x000003ff98f239a8 in abort () at /lib64/libc.so.6
#2 0x000003ff98f3632e in __assert_fail_base () at /lib64/libc.so.6
#3 0x000003ff98f363ac in () at /lib64/libc.so.6
#4 0x000000000108301a in qemu_balloon_inhibit (state=state@entry=false) at
/home/cborntra/REPOS/qemu/balloon.c:56
#5 0x00000000012026f2 in postcopy_ram_incoming_cleanup
(mis=mis@entry=0x163bc5c0) at
/home/cborntra/REPOS/qemu/migration/postcopy-ram.c:542
#6 0x00000000011eed5e in process_incoming_migration_co (opaque=<optimized
out>) at /home/cborntra/REPOS/qemu/migration/migration.c:407
#7 0x0000000001374000 in coroutine_trampoline (i0=<optimized out>,
i1=<optimized out>) at /home/cborntra/REPOS/qemu/util/coroutine-ucontext.c:116
#8 0x000003ff98f53c02 in __makecontext_ret () at /lib64/libc.so.6
Cant see right now whats wrong.
On 08/17/2018 07:08 PM, Alex Williamson wrote:
> A simple true/false internal state does not allow multiple users. Fix
> this within the existing interface by converting to a counter, so long
> as the counter is elevated, ballooning is inhibited.
>
> Reviewed-by: David Hildenbrand <da...@redhat.com>
> Reviewed-by: Peter Xu <pet...@redhat.com>
> Reviewed-by: Cornelia Huck <coh...@redhat.com>
> Signed-off-by: Alex Williamson <alex.william...@redhat.com>
> ---
> balloon.c | 13 ++++++++++---
> 1 file changed, 10 insertions(+), 3 deletions(-)
>
> diff --git a/balloon.c b/balloon.c
> index 6bf0a9681377..931987983858 100644
> --- a/balloon.c
> +++ b/balloon.c
> @@ -26,6 +26,7 @@
>
> #include "qemu/osdep.h"
> #include "qemu-common.h"
> +#include "qemu/atomic.h"
> #include "exec/cpu-common.h"
> #include "sysemu/kvm.h"
> #include "sysemu/balloon.h"
> @@ -37,16 +38,22 @@
> static QEMUBalloonEvent *balloon_event_fn;
> static QEMUBalloonStatus *balloon_stat_fn;
> static void *balloon_opaque;
> -static bool balloon_inhibited;
> +static int balloon_inhibit_count;
>
> bool qemu_balloon_is_inhibited(void)
> {
> - return balloon_inhibited;
> + return atomic_read(&balloon_inhibit_count) > 0;
> }
>
> void qemu_balloon_inhibit(bool state)
> {
> - balloon_inhibited = state;
> + if (state) {
> + atomic_inc(&balloon_inhibit_count);
> + } else {
> + atomic_dec(&balloon_inhibit_count);
> + }
> +
> + assert(atomic_read(&balloon_inhibit_count) >= 0);
> }
>
> static bool have_balloon(Error **errp)
>
>
