Re: [Qemu-devel] [PATCH] Revert "ide/ahci: Check for -ECANCELED in aio callbacks"

["Philippe Mathieu-Daudé" <philmd@redhat.com>]

Hi John,

On 7/30/19 12:36 AM, John Snow wrote:
> This reverts commit 0d910cfeaf2076b116b4517166d5deb0fea76394.
> 
> It's not correct to just ignore an error code in a callback; we need to
> handle that error and possible report failure to the guest so that they
> don't wait indefinitely for an operation that will now never finish.

Is this 4.1 material? It looks so.

> This ought to help cases reported by Nutanix where iSCSI returns a
> legitimate -ECANCELED for certain operations which should be propagated
> normally.
> 
> Reported-by: Shaju Abraham <shaju.abraham@nutanix.com>
> Signed-off-by: John Snow <jsnow@redhat.com>
> ---
>  hw/ide/ahci.c |  3 ---
>  hw/ide/core.c | 14 --------------
>  2 files changed, 17 deletions(-)
> 
> diff --git a/hw/ide/ahci.c b/hw/ide/ahci.c
> index 00ba422a48..6aaf66534a 100644
> --- a/hw/ide/ahci.c
> +++ b/hw/ide/ahci.c
> @@ -1023,9 +1023,6 @@ static void ncq_cb(void *opaque, int ret)
>      IDEState *ide_state = &ncq_tfs->drive->port.ifs[0];
>  
>      ncq_tfs->aiocb = NULL;
> -    if (ret == -ECANCELED) {
> -        return;
> -    }
>  
>      if (ret < 0) {
>          bool is_read = ncq_tfs->cmd == READ_FPDMA_QUEUED;
> diff --git a/hw/ide/core.c b/hw/ide/core.c
> index 6afadf894f..8e1624f7ce 100644
> --- a/hw/ide/core.c
> +++ b/hw/ide/core.c
> @@ -722,9 +722,6 @@ static void ide_sector_read_cb(void *opaque, int ret)
>      s->pio_aiocb = NULL;
>      s->status &= ~BUSY_STAT;
>  
> -    if (ret == -ECANCELED) {
> -        return;
> -    }
>      if (ret != 0) {
>          if (ide_handle_rw_error(s, -ret, IDE_RETRY_PIO |
>                                  IDE_RETRY_READ)) {
> @@ -840,10 +837,6 @@ static void ide_dma_cb(void *opaque, int ret)
>      uint64_t offset;
>      bool stay_active = false;
>  
> -    if (ret == -ECANCELED) {
> -        return;
> -    }
> -
>      if (ret == -EINVAL) {
>          ide_dma_error(s);
>          return;
> @@ -975,10 +968,6 @@ static void ide_sector_write_cb(void *opaque, int ret)
>      IDEState *s = opaque;
>      int n;
>  
> -    if (ret == -ECANCELED) {
> -        return;
> -    }
> -
>      s->pio_aiocb = NULL;
>      s->status &= ~BUSY_STAT;
>  
> @@ -1058,9 +1047,6 @@ static void ide_flush_cb(void *opaque, int ret)
>  
>      s->pio_aiocb = NULL;
>  
> -    if (ret == -ECANCELED) {
> -        return;
> -    }
>      if (ret < 0) {
>          /* XXX: What sector number to set here? */
>          if (ide_handle_rw_error(s, -ret, IDE_RETRY_FLUSH)) {
>