According to CXL 2.0 8.2.9.5.2.1 table 176, the next Persistent
Bytes should be calculated by next Persistent Capacity.
Signed-off-by: Huaisheng Ye <[email protected]>
---
drivers/cxl/core/mbox.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/cxl/core/mbox.c b/drivers/cxl/core/mbox.c
index 36270dcfb42e..7b8ec73ca37f 100644
--- a/drivers/cxl/core/mbox.c
+++ b/drivers/cxl/core/mbox.c
@@ -1069,7 +1069,7 @@ static int cxl_mem_get_partition_info(struct cxl_memdev_state *mds)
mds->next_volatile_bytes =
le64_to_cpu(pi.next_volatile_cap) * CXL_CAPACITY_MULTIPLIER;
mds->next_persistent_bytes =
- le64_to_cpu(pi.next_volatile_cap) * CXL_CAPACITY_MULTIPLIER;
+ le64_to_cpu(pi.next_persistent_cap) * CXL_CAPACITY_MULTIPLIER;
return 0;
}
--
2.39.0
Huaisheng Ye wrote:
> According to CXL 2.0 8.2.9.5.2.1 table 176, the next Persistent
> Bytes should be calculated by next Persistent Capacity.
>
> Signed-off-by: Huaisheng Ye <[email protected]>
Do we have a fixes tag for this? Was there a bug associated with this
find?
Ira
> ---
> drivers/cxl/core/mbox.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/cxl/core/mbox.c b/drivers/cxl/core/mbox.c
> index 36270dcfb42e..7b8ec73ca37f 100644
> --- a/drivers/cxl/core/mbox.c
> +++ b/drivers/cxl/core/mbox.c
> @@ -1069,7 +1069,7 @@ static int cxl_mem_get_partition_info(struct cxl_memdev_state *mds)
> mds->next_volatile_bytes =
> le64_to_cpu(pi.next_volatile_cap) * CXL_CAPACITY_MULTIPLIER;
> mds->next_persistent_bytes =
> - le64_to_cpu(pi.next_volatile_cap) * CXL_CAPACITY_MULTIPLIER;
> + le64_to_cpu(pi.next_persistent_cap) * CXL_CAPACITY_MULTIPLIER;
>
> return 0;
> }
> --
> 2.39.0
>
On 2023-12-06 05:48, Ira Weiny wrote:
> Huaisheng Ye wrote:
>> According to CXL 2.0 8.2.9.5.2.1 table 176, the next Persistent
>> Bytes should be calculated by next Persistent Capacity.
>>
>> Signed-off-by: Huaisheng Ye <[email protected]>
> Do we have a fixes tag for this? Was there a bug associated with this
> find?
>
> Ira
Hi Ira,
This bug could be found in cxl-next branch.
It looks like just cxl-pci would calculate next_persistent_bytes during
probe. Afterwards, it will no longer be accessed by current cxl drivers.
For v78 ndctl, cxl_cmd_partition_get_next_persistent_size is calculated from
next_persistent, which is correct.
May I have your Reviewed-by?
Huaisheng
Huaisheng Ye wrote:
>
>
> On 2023-12-06 05:48, Ira Weiny wrote:
> > Huaisheng Ye wrote:
> >> According to CXL 2.0 8.2.9.5.2.1 table 176, the next Persistent
> >> Bytes should be calculated by next Persistent Capacity.
> >>
> >> Signed-off-by: Huaisheng Ye <[email protected]>
> > Do we have a fixes tag for this? Was there a bug associated with this
> > find?
> >
> > Ira
>
> Hi Ira,
Hey... First off thanks for the patch. This is obviously something which
is wrong. I'm just trying to get more details about how much work should
be done to fix this.
>
> This bug could be found in cxl-next branch.
This looks like it has been a bug for a while.
59f8d1510739e (Dan Williams 2023-06-14 18:30:02 -0700 1071) mds->next_persistent_bytes =
4faf31b43468c (Dan Williams 2021-09-08 22:12:32 -0700 1072) le64_to_cpu(pi.next_volatile_cap) * CXL_CAPACITY_MULTIPLIER;
Both of those commits were refactoring so the fixes goes back a bit more.
My question is: what problem is this causing for the user and should we ID
which commit's this fixes for potential backporting to stable kernels?
Do you have that information?
> It looks like just cxl-pci would calculate next_persistent_bytes during
> probe. Afterwards, it will no longer be accessed by current cxl drivers.
>
> For v78 ndctl, cxl_cmd_partition_get_next_persistent_size is calculated from
> next_persistent, which is correct.
This too seems to be old behavior.
4f588b964dccf (Alison Schofield 2022-02-22 11:56:03 -0800 4142)cxl_cmd_partition_get_next_persistent_size(struct cxl_cmd *cmd)
>
> May I have your Reviewed-by?
Not yet. I want to know should this be backported and what problems this
causes. The next values are not going to take effect until the next
reboot/reset of the device. So they are basically informational, Right?.
Is that why you did not add a fixes to the patch? If so mention that a
fixes is not needed. If not, explain why this is something a user might
see and lets figure out what fixes tags to add so this gets backported.
Thanks,
Ira