[PATCH-for-9.1 v2] hw/ide/pci.c: Remove dead code from bmdma_prepare_buf()

[PATCH-for-9.1 v2] hw/ide/pci.c: Remove dead code from bmdma_prepare_buf()

[Philippe Mathieu-Daudé]

From: Peter Maydell <peter.maydell@linaro.org>

Coverity notes that the code at the end of the loop in
bmdma_prepare_buf() is unreachable.  This is because in commit
9fbf0fa81fca8f527 ("ide: remove hardcoded 2GiB transactional limit")
we removed the only codepath in the loop which could "break" out of
it, but didn't notice that this meant we should also remove the code
at the end of the loop.

Remove the dead code.

Resolves: Coverity CID 1547772
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
---
v2: Break and return once at EOF
---
 hw/ide/pci.c | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/hw/ide/pci.c b/hw/ide/pci.c
index 4675d079a1..a008fe7316 100644
--- a/hw/ide/pci.c
+++ b/hw/ide/pci.c
@@ -237,7 +237,7 @@ static int32_t bmdma_prepare_buf(const IDEDMA *dma, int32_t limit)
             /* end of table (with a fail safe of one page) */
             if (bm->cur_prd_last ||
                 (bm->cur_addr - bm->addr) >= BMDMA_PAGE_SIZE) {
-                return s->sg.size;
+                break;
             }
             pci_dma_read(pci_dev, bm->cur_addr, &prd, 8);
             bm->cur_addr += 8;
@@ -266,10 +266,7 @@ static int32_t bmdma_prepare_buf(const IDEDMA *dma, int32_t limit)
             s->io_buffer_size += l;
         }
     }
-
-    qemu_sglist_destroy(&s->sg);
-    s->io_buffer_size = 0;
-    return -1;
+    return s->sg.size;
 }
 
 /* return 0 if buffer completed */
-- 
2.45.2

Re: [PATCH-for-9.1 v2] hw/ide/pci.c: Remove dead code from bmdma_prepare_buf()

[Richard Henderson]

On 8/6/24 04:24, Philippe Mathieu-Daudé wrote:
> From: Peter Maydell<peter.maydell@linaro.org>
> 
> Coverity notes that the code at the end of the loop in
> bmdma_prepare_buf() is unreachable.  This is because in commit
> 9fbf0fa81fca8f527 ("ide: remove hardcoded 2GiB transactional limit")
> we removed the only codepath in the loop which could "break" out of
> it, but didn't notice that this meant we should also remove the code
> at the end of the loop.
> 
> Remove the dead code.
> 
> Resolves: Coverity CID 1547772
> Signed-off-by: Peter Maydell<peter.maydell@linaro.org>
> Reviewed-by: Kevin Wolf<kwolf@redhat.com>
> Reviewed-by: Philippe Mathieu-Daudé<philmd@linaro.org>
> Signed-off-by: Philippe Mathieu-Daudé<philmd@linaro.org>
> ---
> v2: Break and return once at EOF
> ---
>   hw/ide/pci.c | 7 ++-----
>   1 file changed, 2 insertions(+), 5 deletions(-)

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>

r~

Re: [PATCH-for-9.1 v2] hw/ide/pci.c: Remove dead code from bmdma_prepare_buf()

[Philippe Mathieu-Daudé]

On 5/8/24 20:24, Philippe Mathieu-Daudé wrote:
> From: Peter Maydell <peter.maydell@linaro.org>
> 
> Coverity notes that the code at the end of the loop in
> bmdma_prepare_buf() is unreachable.  This is because in commit
> 9fbf0fa81fca8f527 ("ide: remove hardcoded 2GiB transactional limit")
> we removed the only codepath in the loop which could "break" out of
> it, but didn't notice that this meant we should also remove the code
> at the end of the loop.
> 
> Remove the dead code.
> 
> Resolves: Coverity CID 1547772
> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
> Reviewed-by: Kevin Wolf <kwolf@redhat.com>
> Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
> Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
> ---
> v2: Break and return once at EOF
> ---
>   hw/ide/pci.c | 7 ++-----
>   1 file changed, 2 insertions(+), 5 deletions(-)

Patch queued.