qemu/block
Stefan Hajnoczi cf4fbc3030 block/nvme: fix infinite loop in nvme_free_req_queue_cb()
When the request free list is exhausted the coroutine waits on
q->free_req_queue for the next free request. Whenever a request is
completed a BH is scheduled to invoke nvme_free_req_queue_cb() and wake
up waiting coroutines.

1. nvme_get_free_req() waits for a free request:

    while (q->free_req_head == -1) {
        ...
            trace_nvme_free_req_queue_wait(q->s, q->index);
            qemu_co_queue_wait(&q->free_req_queue, &q->lock);
        ...
    }

2. nvme_free_req_queue_cb() wakes up the coroutine:

    while (qemu_co_enter_next(&q->free_req_queue, &q->lock)) {
       ^--- infinite loop when free_req_head == -1
    }

nvme_free_req_queue_cb() and the coroutine form an infinite loop when
q->free_req_head == -1. Fix this by checking q->free_req_head in
nvme_free_req_queue_cb(). If the free request list is exhausted, don't
wake waiting coroutines. Eventually an in-flight request will complete
and the BH will be scheduled again, guaranteeing forward progress.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20211208152246.244585-1-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2021-12-09 09:19:49 +00:00
..
export block/export/fuse.c: fix musl build 2021-11-02 13:02:46 +01:00
monitor block/monitor: Consolidate hmp_handle_error calls to reduce redundant code 2021-09-01 12:57:31 +02:00
accounting.c block/accounting: Use lock guard macros 2020-12-11 17:52:39 +01:00
aio_task.c block/aio_task: assert max_busy_tasks is greater than 0 2021-10-05 18:56:41 +02:00
amend.c block/amend: Check whether the node exists 2020-07-27 12:37:25 +02:00
backup.c jobs: Give Job.force_cancel more meaning 2021-10-07 10:42:34 +02:00
blkdebug.c block: use int64_t instead of int in driver discard handlers 2021-09-29 13:46:32 -05:00
blklogwrites.c block: use int64_t instead of int in driver discard handlers 2021-09-29 13:46:32 -05:00
blkreplay.c block: use int64_t instead of int in driver discard handlers 2021-09-29 13:46:32 -05:00
blkverify.c block: use int64_t instead of uint64_t in driver write handlers 2021-09-29 13:46:31 -05:00
block-backend.c block-backend: Silence clang -m32 compiler warning 2021-11-02 13:22:09 +01:00
block-copy.c block/block-copy: block_copy_state_new(): drop extra arguments 2021-09-01 14:38:08 +02:00
block-gen.h scripts: add block-coroutine-wrapper.py 2020-10-05 10:59:06 +01:00
bochs.c block: use int64_t instead of uint64_t in driver read handlers 2021-09-29 13:46:31 -05:00
cloop.c block: use int64_t instead of uint64_t in driver read handlers 2021-09-29 13:46:31 -05:00
commit.c block: use int64_t instead of uint64_t in driver read handlers 2021-09-29 13:46:31 -05:00
copy-before-write.c block: use int64_t instead of int in driver discard handlers 2021-09-29 13:46:32 -05:00
copy-before-write.h block/copy-before-write: bdrv_cbw_append(): drop unused compress arg 2021-09-01 14:03:47 +02:00
copy-on-read.c block: use int64_t instead of int in driver discard handlers 2021-09-29 13:46:32 -05:00
copy-on-read.h copy-on-read: add filter drop function 2021-01-26 11:26:54 +01:00
coroutines.h block-backend: drop blk_prw, use block-coroutine-wrapper 2021-10-15 15:53:24 -05:00
create.c
crypto.c block: use int64_t instead of uint64_t in driver write handlers 2021-09-29 13:46:31 -05:00
crypto.h nomaintainer: Fix Lesser GPL version number 2020-11-15 17:04:40 +01:00
curl.c block: use int64_t instead of uint64_t in driver read handlers 2021-09-29 13:46:31 -05:00
dirty-bitmap.c iotests: Improve and rename test 291 to qemu-img-bitmap 2021-07-21 14:14:41 -05:00
dmg-bz2.c
dmg-lzfse.c block: Remove unused include 2020-11-09 15:44:21 +01:00
dmg.c block: use int64_t instead of uint64_t in driver read handlers 2021-09-29 13:46:31 -05:00
dmg.h
file-posix.c file-posix: Fix alignment after reopen changing O_DIRECT 2021-11-16 11:30:29 +01:00
file-win32.c block: use int64_t instead of uint64_t in driver write handlers 2021-09-29 13:46:31 -05:00
filter-compress.c block: use int64_t instead of int in driver discard handlers 2021-09-29 13:46:32 -05:00
gluster.c block: use int64_t instead of int in driver discard handlers 2021-09-29 13:46:32 -05:00
io_uring.c block/io_uring: resubmit when result is -EAGAIN 2021-07-29 17:14:55 +01:00
io.c block: introduce max_hw_iov for use in scsi-generic 2021-10-06 10:25:55 +02:00
iscsi-opts.c modules: add block module annotations 2021-07-09 18:20:27 +02:00
iscsi.c block: use int64_t instead of int in driver discard handlers 2021-09-29 13:46:32 -05:00
linux-aio.c linux-aio: add dev_max_batch parameter to laio_io_unplug() 2021-11-02 13:03:35 +01:00
meson.build configure, meson: move libaio check to meson.build 2021-10-14 09:50:57 +02:00
mirror.c mirror: Do not clear .cancelled 2021-10-07 10:42:50 +02:00
nbd.c block/nbd: check that received handle is valid 2021-09-29 13:46:33 -05:00
nfs.c block: use int64_t instead of uint64_t in driver write handlers 2021-09-29 13:46:31 -05:00
null.c block: use int64_t instead of uint64_t in driver write handlers 2021-09-29 13:46:31 -05:00
nvme.c block/nvme: fix infinite loop in nvme_free_req_queue_cb() 2021-12-09 09:19:49 +00:00
parallels-ext.c parallels: support bitmap extension for read-only mode 2021-03-08 14:56:55 +01:00
parallels.c parallels: support bitmap extension for read-only mode 2021-03-08 14:56:55 +01:00
parallels.h parallels: support bitmap extension for read-only mode 2021-03-08 14:56:55 +01:00
preallocate.c block: use int64_t instead of int in driver discard handlers 2021-09-29 13:46:32 -05:00
progress_meter.c progressmeter: protect with a mutex 2021-06-25 14:24:24 +03:00
qapi-sysemu.c
qapi.c block: use GDateTime for formatting timestamp when dumping snapshot info 2021-06-14 13:28:50 +01:00
qcow2-bitmap.c nbd patches for 2021-03-09 2021-03-11 13:57:08 +00:00
qcow2-cache.c
qcow2-cluster.c qcow2: Silence clang -m32 compiler warning 2021-10-15 15:39:38 -05:00
qcow2-refcount.c qcow2-refcount: check_refblocks(): add separate message for reserved 2021-09-15 18:42:38 +02:00
qcow2-snapshot.c block: consistently use bdrv_is_read_only() 2021-06-02 14:23:20 +02:00
qcow2-threads.c
qcow2.c block: use int64_t instead of int in driver discard handlers 2021-09-29 13:46:32 -05:00
qcow2.h qcow2-refcount: check_refblocks(): add separate message for reserved 2021-09-15 18:42:38 +02:00
qcow.c block: use int64_t instead of uint64_t in driver write handlers 2021-09-29 13:46:31 -05:00
qed-check.c
qed-cluster.c
qed-l2-cache.c
qed-table.c
qed.c block: use int64_t instead of int in driver write_zeroes handlers 2021-09-29 13:46:32 -05:00
qed.h qed: Simplify backing reads 2020-07-06 10:34:14 +02:00
quorum.c block: use int64_t instead of int in driver write_zeroes handlers 2021-09-29 13:46:32 -05:00
raw-format.c block: use int64_t instead of int in driver discard handlers 2021-09-29 13:46:32 -05:00
rbd.c block/rbd: implement bdrv_co_block_status 2021-11-02 13:02:46 +01:00
replication.c job: @force parameter for job_cancel_sync() 2021-10-07 10:42:09 +02:00
snapshot.c block/snapshot: Clarify goto fallback behavior 2021-06-24 09:49:04 +02:00
ssh.c util/uri: do not check argument of uri_free() 2021-07-09 12:26:05 +02:00
stream.c stream: Traverse graph after modification 2021-11-16 09:43:23 +01:00
throttle-groups.c block/throttle-groups: throttle_group_co_io_limits_intercept(): 64bit bytes 2021-02-03 08:14:00 -06:00
throttle.c block: use int64_t instead of int in driver discard handlers 2021-09-29 13:46:32 -05:00
trace-events block/nvme: Display CQ/SQ pointer in nvme_free_queue_pair() 2021-11-02 15:49:12 +01:00
trace.h trace: switch position of headers to what Meson requires 2020-08-21 06:18:24 -04:00
vdi.c block: use int64_t instead of uint64_t in driver write handlers 2021-09-29 13:46:31 -05:00
vhdx-endian.c
vhdx-log.c block: consistently use bdrv_is_read_only() 2021-06-02 14:23:20 +02:00
vhdx.c block/vhdx: Support vhdx image only with 512 bytes logical sector size 2020-09-15 11:05:13 +02:00
vhdx.h
vmdk.c vmdk: allow specification of tools version 2021-11-02 12:47:51 +01:00
vpc.c block/vpc: Add a sanity check that fixed-size images have the right type 2021-11-02 12:47:51 +01:00
vvfat.c block/vvfat.c fix leak when failure occurs 2021-11-23 15:39:12 +01:00
win32-aio.c
write-threshold.c write-threshold: deal with includes 2021-05-14 16:14:10 +02:00