riscv/qemu - qemu - Gitea: Git with a cup of tea

Author	SHA1	Message	Date
Fiona Ebner	6475155d51	block/reqlist: allow adding overlapping requests Allow overlapping request by removing the assert that made it impossible. There are only two callers: 1. block_copy_task_create() It already asserts the very same condition before calling reqlist_init_req(). 2. cbw_snapshot_read_lock() There is no need to have read requests be non-overlapping in copy-before-write when used for snapshot-access. In fact, there was no protection against two callers of cbw_snapshot_read_lock() calling reqlist_init_req() with overlapping ranges and this could lead to an assertion failure [1]. In particular, with the reproducer script below [0], two cbw_co_snapshot_block_status() callers could race, with the second calling reqlist_init_req() before the first one finishes and removes its conflicting request. [0]: > #!/bin/bash -e > dd if=/dev/urandom of=/tmp/disk.raw bs=1M count=1024 > ./qemu-img create /tmp/fleecing.raw -f raw 1G > ( > ./qemu-system-x86_64 --qmp stdio \ > --blockdev raw,node-name=node0,file.driver=file,file.filename=/tmp/disk.raw \ > --blockdev raw,node-name=node1,file.driver=file,file.filename=/tmp/fleecing.raw \ > <<EOF > {"execute": "qmp_capabilities"} > {"execute": "blockdev-add", "arguments": { "driver": "copy-before-write", "file": "node0", "target": "node1", "node-name": "node3" } } > {"execute": "blockdev-add", "arguments": { "driver": "snapshot-access", "file": "node3", "node-name": "snap0" } } > {"execute": "nbd-server-start", "arguments": {"addr": { "type": "unix", "data": { "path": "/tmp/nbd.socket" } } } } > {"execute": "block-export-add", "arguments": {"id": "exp0", "node-name": "snap0", "type": "nbd", "name": "exp0"}} > EOF > ) & > sleep 5 > while true; do > ./qemu-nbd -d /dev/nbd0 > ./qemu-nbd -c /dev/nbd0 nbd:unix:/tmp/nbd.socket:exportname=exp0 -f raw -r > nbdinfo --map 'nbd+unix:///exp0?socket=/tmp/nbd.socket' > done [1]: > #5 0x000071e5f0088eb2 in __GI___assert_fail (...) at ./assert/assert.c:101 > #6 0x0000615285438017 in reqlist_init_req (...) at ../block/reqlist.c:23 > #7 0x00006152853e2d98 in cbw_snapshot_read_lock (...) at ../block/copy-before-write.c:237 > #8 0x00006152853e3068 in cbw_co_snapshot_block_status (...) at ../block/copy-before-write.c:304 > #9 0x00006152853f4d22 in bdrv_co_snapshot_block_status (...) at ../block/io.c:3726 > #10 0x000061528543a63e in snapshot_access_co_block_status (...) at ../block/snapshot-access.c:48 > #11 0x00006152853f1a0a in bdrv_co_do_block_status (...) at ../block/io.c:2474 > #12 0x00006152853f2016 in bdrv_co_common_block_status_above (...) at ../block/io.c:2652 > #13 0x00006152853f22cf in bdrv_co_block_status_above (...) at ../block/io.c:2732 > #14 0x00006152853d9a86 in blk_co_block_status_above (...) at ../block/block-backend.c:1473 > #15 0x000061528538da6c in blockstatus_to_extents (...) at ../nbd/server.c:2374 > #16 0x000061528538deb1 in nbd_co_send_block_status (...) at ../nbd/server.c:2481 > #17 0x000061528538f424 in nbd_handle_request (...) at ../nbd/server.c:2978 > #18 0x000061528538f906 in nbd_trip (...) at ../nbd/server.c:3121 > #19 0x00006152855a7caf in coroutine_trampoline (...) at ../util/coroutine-ucontext.c:175 Cc: qemu-stable@nongnu.org Suggested-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Signed-off-by: Fiona Ebner <f.ebner@proxmox.com> Message-Id: <20240712140716.517911-1-f.ebner@proxmox.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>	2 years ago
Vladimir Sementsov-Ogievskiy	3b7ca26bdf	block/reqlist: add reqlist_wait_all() Add function to wait for all intersecting requests. To be used in the further commit. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Nikita Lapshin <nikita.lapshin@virtuozzo.com> Reviewed-by: Hanna Reitz <hreitz@redhat.com> Message-Id: <20220303194349.2304213-10-vsementsov@virtuozzo.com> Signed-off-by: Hanna Reitz <hreitz@redhat.com>	5 years ago
Vladimir Sementsov-Ogievskiy	84b1e80f67	block/reqlist: reqlist_find_conflict(): use ranges_overlap() Let's reuse convenient helper. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Hanna Reitz <hreitz@redhat.com> Message-Id: <20220303194349.2304213-8-vsementsov@virtuozzo.com> Signed-off-by: Hanna Reitz <hreitz@redhat.com>	5 years ago
Vladimir Sementsov-Ogievskiy	d088e6a48a	block: intoduce reqlist Split intersecting-requests functionality out of block-copy to be reused in copy-before-write filter. Note: while being here, fix tiny typo in MAINTAINERS. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Hanna Reitz <hreitz@redhat.com> Message-Id: <20220303194349.2304213-7-vsementsov@virtuozzo.com> Signed-off-by: Hanna Reitz <hreitz@redhat.com>	5 years ago