* [PATCH] xen-front-pgdir-shbuf: don't record wrong grant handle upon error
@ 2021-02-23 16:26 Jan Beulich
2021-02-23 18:28 ` Oleksandr Andrushchenko
0 siblings, 1 reply; 3+ messages in thread
From: Jan Beulich @ 2021-02-23 16:26 UTC (permalink / raw)
To: Juergen Gross, Boris Ostrovsky; +Cc: xen-devel, oleksandr_andrushchenko
In order for subsequent unmapping to not mistakenly unmap handle 0,
record a perceived always-invalid one instead.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
---
v2: Use INVALID_GRANT_HANDLE.
--- a/drivers/xen/xen-front-pgdir-shbuf.c
+++ b/drivers/xen/xen-front-pgdir-shbuf.c
@@ -305,11 +305,18 @@ static int backend_map(struct xen_front_
/* Save handles even if error, so we can unmap. */
for (cur_page = 0; cur_page < buf->num_pages; cur_page++) {
- buf->backend_map_handles[cur_page] = map_ops[cur_page].handle;
- if (unlikely(map_ops[cur_page].status != GNTST_okay))
+ if (likely(map_ops[cur_page].status == GNTST_okay)) {
+ buf->backend_map_handles[cur_page] =
+ map_ops[cur_page].handle;
+ } else {
+ buf->backend_map_handles[cur_page] =
+ INVALID_GRANT_HANDLE;
+ if (!ret)
+ ret = -ENXIO;
dev_err(&buf->xb_dev->dev,
"Failed to map page %d: %d\n",
cur_page, map_ops[cur_page].status);
+ }
}
if (ret) {
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [PATCH] xen-front-pgdir-shbuf: don't record wrong grant handle upon error
2021-02-23 16:26 [PATCH] xen-front-pgdir-shbuf: don't record wrong grant handle upon error Jan Beulich
@ 2021-02-23 18:28 ` Oleksandr Andrushchenko
2021-02-24 0:31 ` Boris Ostrovsky
0 siblings, 1 reply; 3+ messages in thread
From: Oleksandr Andrushchenko @ 2021-02-23 18:28 UTC (permalink / raw)
To: Jan Beulich, Juergen Gross, Boris Ostrovsky; +Cc: xen-devel
Hello, Jan!
On 2/23/21 6:26 PM, Jan Beulich wrote:
> In order for subsequent unmapping to not mistakenly unmap handle 0,
> record a perceived always-invalid one instead.
>
> Signed-off-by: Jan Beulich <jbeulich@suse.com>
> Reviewed-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
> ---
> v2: Use INVALID_GRANT_HANDLE.
>
> --- a/drivers/xen/xen-front-pgdir-shbuf.c
> +++ b/drivers/xen/xen-front-pgdir-shbuf.c
> @@ -305,11 +305,18 @@ static int backend_map(struct xen_front_
>
> /* Save handles even if error, so we can unmap. */
> for (cur_page = 0; cur_page < buf->num_pages; cur_page++) {
> - buf->backend_map_handles[cur_page] = map_ops[cur_page].handle;
> - if (unlikely(map_ops[cur_page].status != GNTST_okay))
> + if (likely(map_ops[cur_page].status == GNTST_okay)) {
> + buf->backend_map_handles[cur_page] =
> + map_ops[cur_page].handle;
> + } else {
> + buf->backend_map_handles[cur_page] =
> + INVALID_GRANT_HANDLE;
> + if (!ret)
> + ret = -ENXIO;
> dev_err(&buf->xb_dev->dev,
> "Failed to map page %d: %d\n",
> cur_page, map_ops[cur_page].status);
> + }
> }
>
> if (ret) {
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [PATCH] xen-front-pgdir-shbuf: don't record wrong grant handle upon error
2021-02-23 18:28 ` Oleksandr Andrushchenko
@ 2021-02-24 0:31 ` Boris Ostrovsky
0 siblings, 0 replies; 3+ messages in thread
From: Boris Ostrovsky @ 2021-02-24 0:31 UTC (permalink / raw)
To: Oleksandr Andrushchenko, Jan Beulich, Juergen Gross; +Cc: xen-devel
On 2/23/21 1:28 PM, Oleksandr Andrushchenko wrote:
> Hello, Jan!
>
> On 2/23/21 6:26 PM, Jan Beulich wrote:
>> In order for subsequent unmapping to not mistakenly unmap handle 0,
>> record a perceived always-invalid one instead.
>>
>> Signed-off-by: Jan Beulich <jbeulich@suse.com>
>> Reviewed-by: Juergen Gross <jgross@suse.com>
> Reviewed-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Applied to for-linus-5.12b
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2021-02-24 0:32 UTC | newest]
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2021-02-23 16:26 [PATCH] xen-front-pgdir-shbuf: don't record wrong grant handle upon error Jan Beulich
2021-02-23 18:28 ` Oleksandr Andrushchenko
2021-02-24 0:31 ` Boris Ostrovsky
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