io: deal with blocking/non-blocking fds

[PATCH 10/10] migration/qemu-file: don't make incoming fds blocking again

Vladimir Sementsov-Ogievskiy posted 10 patches 3 days, 4 hours ago

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[PATCH 10/10] migration/qemu-file: don't make incoming fds blocking again

Posted by Vladimir Sementsov-Ogievskiy 3 days, 4 hours ago

In migration we want to pass fd "as is", not changing its
blocking status.

The only current user of these fds is CPR state (through VMSTATE_FD),
which of-course doesn't want to modify fds on target when source is
still running and use these fds.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
---
 migration/qemu-file.c | 6 ------
 1 file changed, 6 deletions(-)

diff --git a/migration/qemu-file.c b/migration/qemu-file.c
index b1d042e298..b6ac190034 100644
--- a/migration/qemu-file.c
+++ b/migration/qemu-file.c
@@ -361,12 +361,6 @@ static ssize_t coroutine_mixed_fn qemu_fill_buffer(QEMUFile *f)
         qemu_file_set_error_obj(f, len, local_error);
     }
 
-    /*
-     * NOTE: don't worry about error_abort, it will be removed
-     * in the next commit
-     */
-    qemu_fds_set_blockinging(fds, nfd, true, &error_abort);
-
     for (int i = 0; i < nfd; i++) {
         FdEntry *fde = g_new0(FdEntry, 1);
         fde->fd = fds[i];
-- 
2.48.1

Re: [PATCH 10/10] migration/qemu-file: don't make incoming fds blocking again

Posted by Vladimir Sementsov-Ogievskiy 3 days, 4 hours ago

CC Steve

On 03.09.25 12:44, Vladimir Sementsov-Ogievskiy wrote:
> In migration we want to pass fd "as is", not changing its
> blocking status.
> 
> The only current user of these fds is CPR state (through VMSTATE_FD),
> which of-course doesn't want to modify fds on target when source is
> still running and use these fds.
> 
> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
> ---
>   migration/qemu-file.c | 6 ------
>   1 file changed, 6 deletions(-)
> 
> diff --git a/migration/qemu-file.c b/migration/qemu-file.c
> index b1d042e298..b6ac190034 100644
> --- a/migration/qemu-file.c
> +++ b/migration/qemu-file.c
> @@ -361,12 +361,6 @@ static ssize_t coroutine_mixed_fn qemu_fill_buffer(QEMUFile *f)
>           qemu_file_set_error_obj(f, len, local_error);
>       }
>   
> -    /*
> -     * NOTE: don't worry about error_abort, it will be removed
> -     * in the next commit
> -     */
> -    qemu_fds_set_blockinging(fds, nfd, true, &error_abort);
> -
>       for (int i = 0; i < nfd; i++) {
>           FdEntry *fde = g_new0(FdEntry, 1);
>           fde->fd = fds[i];


-- 
Best regards,
Vladimir