The Wednesday 28 May 2014 à 16:37:45 (+0200), Kevin Wolf wrote :
> Some code in the block layer makes potentially huge allocations. Failure
> is not completely unexpected there, so avoid aborting qemu and handle
> out-of-memory situations gracefully.
>
> This patch addresses the allocations in the qed block driver.
>
> Signed-off-by: Kevin Wolf <kw...@redhat.com>
> Reviewed-by: Stefan Hajnoczi <stefa...@redhat.com>
> ---
> block/qed-check.c | 7 +++++--
> block/qed.c | 6 +++++-
> 2 files changed, 10 insertions(+), 3 deletions(-)
>
> diff --git a/block/qed-check.c b/block/qed-check.c
> index b473dcd..40a882c 100644
> --- a/block/qed-check.c
> +++ b/block/qed-check.c
> @@ -227,8 +227,11 @@ int qed_check(BDRVQEDState *s, BdrvCheckResult *result,
> bool fix)
> };
> int ret;
>
> - check.used_clusters = g_malloc0(((check.nclusters + 31) / 32) *
> - sizeof(check.used_clusters[0]));
> + check.used_clusters = g_try_malloc0(((check.nclusters + 31) / 32) *
> + sizeof(check.used_clusters[0]));
> + if (check.nclusters && check.used_clusters == NULL) {
> + return -ENOMEM;
> + }
>
> check.result->bfi.total_clusters =
> (s->header.image_size + s->header.cluster_size - 1) /
> diff --git a/block/qed.c b/block/qed.c
> index c130e42..f0943d6 100644
> --- a/block/qed.c
> +++ b/block/qed.c
> @@ -1208,7 +1208,11 @@ static void qed_aio_write_inplace(QEDAIOCB *acb,
> uint64_t offset, size_t len)
> struct iovec *iov = acb->qiov->iov;
>
> if (!iov->iov_base) {
> - iov->iov_base = qemu_blockalign(acb->common.bs, iov->iov_len);
> + iov->iov_base = qemu_try_blockalign(acb->common.bs,
> iov->iov_len);
Perhaps a comment for the people not so knowledgable of the block layer
explaining
why a iov with iov_len == 0 can't happen would be helpfull.
> + if (iov->iov_base == NULL) {
> + qed_aio_complete(acb, -ENOMEM);
> + return;
> + }
> memset(iov->iov_base, 0, iov->iov_len);
> }
> }
> --
> 1.8.3.1
>
>
