* Paolo Bonzini (pbonz...@redhat.com) wrote:
> Use WITH_RCU_READ_LOCK_GUARD to avoid exiting colo_init_ram_cache
> without releasing RCU.
>
> Cc: Dr. David Alan Gilbert <dgilb...@redhat.com>
> Signed-off-by: Paolo Bonzini <pbonz...@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilb...@redhat.com>
> ---
> migration/ram.c | 33 +++++++++++++++++----------------
> 1 file changed, 17 insertions(+), 16 deletions(-)
>
> diff --git a/migration/ram.c b/migration/ram.c
> index 7dd7f81..8d7c015 100644
> --- a/migration/ram.c
> +++ b/migration/ram.c
> @@ -3891,26 +3891,27 @@ int colo_init_ram_cache(void)
> {
> RAMBlock *block;
>
> - rcu_read_lock();
> - RAMBLOCK_FOREACH_NOT_IGNORED(block) {
> - block->colo_cache = qemu_anon_ram_alloc(block->used_length,
> - NULL,
> - false);
> - if (!block->colo_cache) {
> - error_report("%s: Can't alloc memory for COLO cache of block %s,"
> - "size 0x" RAM_ADDR_FMT, __func__, block->idstr,
> - block->used_length);
> - RAMBLOCK_FOREACH_NOT_IGNORED(block) {
> - if (block->colo_cache) {
> - qemu_anon_ram_free(block->colo_cache,
> block->used_length);
> - block->colo_cache = NULL;
> + WITH_RCU_READ_LOCK_GUARD() {
> + RAMBLOCK_FOREACH_NOT_IGNORED(block) {
> + block->colo_cache = qemu_anon_ram_alloc(block->used_length,
> + NULL,
> + false);
> + if (!block->colo_cache) {
> + error_report("%s: Can't alloc memory for COLO cache of block
> %s,"
> + "size 0x" RAM_ADDR_FMT, __func__, block->idstr,
> + block->used_length);
> + RAMBLOCK_FOREACH_NOT_IGNORED(block) {
> + if (block->colo_cache) {
> + qemu_anon_ram_free(block->colo_cache,
> block->used_length);
> + block->colo_cache = NULL;
> + }
> }
> + return -errno;
> }
> - return -errno;
> + memcpy(block->colo_cache, block->host, block->used_length);
> }
> - memcpy(block->colo_cache, block->host, block->used_length);
> }
> - rcu_read_unlock();
> +
> /*
> * Record the dirty pages that sent by PVM, we use this dirty bitmap
> together
> * with to decide which page in cache should be flushed into SVM's RAM.
> Here
> --
> 1.8.3.1
>
--
Dr. David Alan Gilbert / dgilb...@redhat.com / Manchester, UK
