From 22dd9405446f5301f32be4f9e88db6d9b582fd03 Mon Sep 17 00:00:00 2001 From: Kevin Wolf Date: Mon, 5 Jun 2023 10:57:09 +0200 Subject: [PATCH] blockjob: Fix AioContext locking in block_job_add_bdrv() bdrv_root_attach_child() requires callers to hold the AioContext lock for child_bs. Take it in block_job_add_bdrv() before calling the function. Signed-off-by: Kevin Wolf Message-ID: <20230605085711.21261-10-kwolf@redhat.com> Reviewed-by: Stefan Hajnoczi Signed-off-by: Kevin Wolf --- blockjob.c | 17 ++++++++++++----- 1 file changed, 12 insertions(+), 5 deletions(-) diff --git a/blockjob.c b/blockjob.c index 913da3cbf7..25fe8e625d 100644 --- a/blockjob.c +++ b/blockjob.c @@ -230,20 +230,27 @@ int block_job_add_bdrv(BlockJob *job, const char *name, BlockDriverState *bs, uint64_t perm, uint64_t shared_perm, Error **errp) { BdrvChild *c; + AioContext *ctx = bdrv_get_aio_context(bs); bool need_context_ops; GLOBAL_STATE_CODE(); bdrv_ref(bs); - need_context_ops = bdrv_get_aio_context(bs) != job->job.aio_context; + need_context_ops = ctx != job->job.aio_context; - if (need_context_ops && job->job.aio_context != qemu_get_aio_context()) { - aio_context_release(job->job.aio_context); + if (need_context_ops) { + if (job->job.aio_context != qemu_get_aio_context()) { + aio_context_release(job->job.aio_context); + } + aio_context_acquire(ctx); } c = bdrv_root_attach_child(bs, name, &child_job, 0, perm, shared_perm, job, errp); - if (need_context_ops && job->job.aio_context != qemu_get_aio_context()) { - aio_context_acquire(job->job.aio_context); + if (need_context_ops) { + aio_context_release(ctx); + if (job->job.aio_context != qemu_get_aio_context()) { + aio_context_acquire(job->job.aio_context); + } } if (c == NULL) { return -EPERM;