| Message ID | 1383881209-24318-1-git-send-email-famz@redhat.com |
|---|---|
| State | New |
| Headers | show |
On 11/07/2013 08:26 PM, Fam Zheng wrote: > If backing file doesn't exist, the error message is confusing and > misleading: > > $ qemu /tmp/a.qcow2 > qemu: could not open disk image /tmp/a.qcow2: Could not open file: No > such file or directory > > This is not intuitive. It's better to have the missing file's name in > the error message. With this patch: > > $ qemu-io -c 'read 0 512' /tmp/a.qcow2 > qemu-io: can't open device /tmp/a.qcow2: Could not open backing > file: Could not open '/stor/vm/arch.raw': No such file or directory > no file open, try 'help open' > > Which is a little bit better. > > Signed-off-by: Fam Zheng <famz@redhat.com> > > --- > v2: Don't leak local_err (Eric). Thanks. Reviewed-by: Eric Blake <eblake@redhat.com>
On Fri, Nov 08, 2013 at 11:26:49AM +0800, Fam Zheng wrote: > If backing file doesn't exist, the error message is confusing and > misleading: > > $ qemu /tmp/a.qcow2 > qemu: could not open disk image /tmp/a.qcow2: Could not open file: No > such file or directory > > But... > > $ ls /tmp/a.qcow2 > /tmp/a.qcow2 > > $ qemu-img info /tmp/a.qcow2 > image: /tmp/a.qcow2 > file format: qcow2 > virtual size: 8.0G (8589934592 bytes) > disk size: 196K > cluster_size: 65536 > backing file: /tmp/b.qcow2 > > Because... > > $ ls /tmp/b.qcow2 > ls: cannot access /tmp/b.qcow2: No such file or directory > > This is not intuitive. It's better to have the missing file's name in > the error message. With this patch: > > $ qemu-io -c 'read 0 512' /tmp/a.qcow2 > qemu-io: can't open device /tmp/a.qcow2: Could not open backing > file: Could not open '/stor/vm/arch.raw': No such file or directory > no file open, try 'help open' > > Which is a little bit better. > > Signed-off-by: Fam Zheng <famz@redhat.com> > > --- > v2: Don't leak local_err (Eric). > > Signed-off-by: Fam Zheng <famz@redhat.com> > --- > block.c | 4 +++- > block/raw-posix.c | 1 - > block/raw-win32.c | 1 - > tests/qemu-iotests/051.out | 2 +- > tests/qemu-iotests/069.out | 2 +- > 5 files changed, 5 insertions(+), 5 deletions(-) Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Am 08.11.2013 um 04:26 hat Fam Zheng geschrieben: > If backing file doesn't exist, the error message is confusing and > misleading: > > $ qemu /tmp/a.qcow2 > qemu: could not open disk image /tmp/a.qcow2: Could not open file: No > such file or directory > > But... > > $ ls /tmp/a.qcow2 > /tmp/a.qcow2 > > $ qemu-img info /tmp/a.qcow2 > image: /tmp/a.qcow2 > file format: qcow2 > virtual size: 8.0G (8589934592 bytes) > disk size: 196K > cluster_size: 65536 > backing file: /tmp/b.qcow2 > > Because... > > $ ls /tmp/b.qcow2 > ls: cannot access /tmp/b.qcow2: No such file or directory > > This is not intuitive. It's better to have the missing file's name in > the error message. With this patch: > > $ qemu-io -c 'read 0 512' /tmp/a.qcow2 > qemu-io: can't open device /tmp/a.qcow2: Could not open backing > file: Could not open '/stor/vm/arch.raw': No such file or directory > no file open, try 'help open' > > Which is a little bit better. > > Signed-off-by: Fam Zheng <famz@redhat.com> Thanks, applied to the block branch. However, while this may be an improvement, it's certainly not what we'd want the error message to look like in the final state. Consider a chain with multiple backing files: qemu-system-x86_64: -drive file=/tmp/d.qcow2: could not open disk image /tmp/d.qcow2: Could not open backing file: Could not open backing file: Could not open backing file: Could not open backing file: Could not open '/tmp/blubber': No such file or directory Kevin
diff --git a/block.c b/block.c index f706634..7ffb08b 100644 --- a/block.c +++ b/block.c @@ -1009,7 +1009,9 @@ int bdrv_open_backing_file(BlockDriverState *bs, QDict *options, Error **errp) bdrv_unref(bs->backing_hd); bs->backing_hd = NULL; bs->open_flags |= BDRV_O_NO_BACKING; - error_propagate(errp, local_err); + error_setg(errp, "Could not open backing file: %s", + error_get_pretty(local_err)); + error_free(local_err); return ret; } pstrcpy(bs->backing_file, sizeof(bs->backing_file), diff --git a/block/raw-posix.c b/block/raw-posix.c index f6d48bb..e1b1ba2 100644 --- a/block/raw-posix.c +++ b/block/raw-posix.c @@ -310,7 +310,6 @@ static int raw_open_common(BlockDriverState *bs, QDict *options, if (ret == -EROFS) { ret = -EACCES; } - error_setg_errno(errp, -ret, "Could not open file"); goto fail; } s->fd = fd; diff --git a/block/raw-win32.c b/block/raw-win32.c index 2741e4d..2bad5a3 100644 --- a/block/raw-win32.c +++ b/block/raw-win32.c @@ -280,7 +280,6 @@ static int raw_open(BlockDriverState *bs, QDict *options, int flags, } else { ret = -EINVAL; } - error_setg_errno(errp, -ret, "Could not open file"); goto fail; } diff --git a/tests/qemu-iotests/051.out b/tests/qemu-iotests/051.out index 15deef6..d351935 100644 --- a/tests/qemu-iotests/051.out +++ b/tests/qemu-iotests/051.out @@ -226,6 +226,6 @@ Testing: -drive file=foo:bar QEMU_PROG: -drive file=foo:bar: could not open disk image foo:bar: Unknown protocol Testing: -drive file.filename=foo:bar -QEMU_PROG: -drive file.filename=foo:bar: could not open disk image ide0-hd0: Could not open file: No such file or directory +QEMU_PROG: -drive file.filename=foo:bar: could not open disk image ide0-hd0: Could not open 'foo:bar': No such file or directory *** done diff --git a/tests/qemu-iotests/069.out b/tests/qemu-iotests/069.out index 3648814..b48306d 100644 --- a/tests/qemu-iotests/069.out +++ b/tests/qemu-iotests/069.out @@ -4,5 +4,5 @@ QA output created by 069 Formatting 'TEST_DIR/t.IMGFMT.base', fmt=IMGFMT size=131072 Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=131072 backing_file='TEST_DIR/t.IMGFMT.base' -qemu-io: can't open device TEST_DIR/t.IMGFMT: Could not open file: No such file or directory +qemu-io: can't open device TEST_DIR/t.IMGFMT: Could not open backing file: Could not open 'TEST_DIR/t.IMGFMT.base': No such file or directory *** done
If backing file doesn't exist, the error message is confusing and misleading: $ qemu /tmp/a.qcow2 qemu: could not open disk image /tmp/a.qcow2: Could not open file: No such file or directory But... $ ls /tmp/a.qcow2 /tmp/a.qcow2 $ qemu-img info /tmp/a.qcow2 image: /tmp/a.qcow2 file format: qcow2 virtual size: 8.0G (8589934592 bytes) disk size: 196K cluster_size: 65536 backing file: /tmp/b.qcow2 Because... $ ls /tmp/b.qcow2 ls: cannot access /tmp/b.qcow2: No such file or directory This is not intuitive. It's better to have the missing file's name in the error message. With this patch: $ qemu-io -c 'read 0 512' /tmp/a.qcow2 qemu-io: can't open device /tmp/a.qcow2: Could not open backing file: Could not open '/stor/vm/arch.raw': No such file or directory no file open, try 'help open' Which is a little bit better. Signed-off-by: Fam Zheng <famz@redhat.com> --- v2: Don't leak local_err (Eric). Signed-off-by: Fam Zheng <famz@redhat.com> --- block.c | 4 +++- block/raw-posix.c | 1 - block/raw-win32.c | 1 - tests/qemu-iotests/051.out | 2 +- tests/qemu-iotests/069.out | 2 +- 5 files changed, 5 insertions(+), 5 deletions(-)