Commit c8992cffbe74 ("Bluetooth: hci_event: Use of a function table to
handle Command Complete") was (presumably) meant to only refactor things
without any functional changes.
But it does have one undesirable side-effect, before *status would always
be set to skb->data[0] and it might be overridden by some of the opcode
specific handling. While now it always set by the opcode specific handlers.
This means that if the opcode is not known *status does not get set any
more at all!
This behavior change has broken bluetooth support for BCM4343A0 HCIs,
the hci_bcm.c code tries to configure UART attached HCIs at a higher
baudraute using vendor specific opcodes. The BCM4343A0 does not
support this and this used to simply fail:
[ 25.646442] Bluetooth: hci0: BCM: failed to write clock (-56)
[ 25.646481] Bluetooth: hci0: Failed to set baudrate
After which things would continue with the initial baudraute. But now
that hci_cmd_complete_evt() no longer sets status for unknown opcodes
*status is left at 0. This causes the hci_bcm.c code to think the baudraute
has been changed on the HCI side and to also adjust the UART baudrate,
after which communication with the HCI is broken, leading to:
[ 28.579042] Bluetooth: hci0: command 0x0c03 tx timeout
[ 36.961601] Bluetooth: hci0: BCM: Reset failed (-110)
And non working bluetooth. Fix this by restoring the previous
default "*status = skb->data[0]" handling for unknown opcodes.
Fixes: c8992cffbe74 ("Bluetooth: hci_event: Use of a function table to handle Command Complete")
Cc: Luiz Augusto von Dentz <[email protected]>
Signed-off-by: Hans de Goede <[email protected]>
---
Changes in v2:
- Add a comment that byte 0 containing the status is not guaranteed
by the Bluetooth specification
---
net/bluetooth/hci_event.c | 20 ++++++++++++++++++++
1 file changed, 20 insertions(+)
diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
index af17dfb20e01..eb43afd5549a 100644
--- a/net/bluetooth/hci_event.c
+++ b/net/bluetooth/hci_event.c
@@ -3996,6 +3996,26 @@ static void hci_cmd_complete_evt(struct hci_dev *hdev, void *data,
break;
}
}
+ if (i == ARRAY_SIZE(hci_cc_table)) {
+ /* Unknown opcode, assume byte 0 contains the status, so
+ * that e.g. __hci_cmd_sync() properly returns errors
+ * for vendor specific commands send by HCI drivers.
+ *
+ * Note that the specification does not specify that
+ * byte 0 is the status:
+ *
+ * BLUETOOTH CORE SPECIFICATION Version 5.3 | Vol 4, Part E
+ * page 2189:
+ *
+ * Return_Parameters:
+ * Size: Depends on command
+ *
+ * For now using byte 0 seems to work fine, but in the future
+ * this may need to be updated so that drivers using vendor
+ * commands can specify their own completion handler.
+ */
+ *status = skb->data[0];
+ }
handle_cmd_cnt_and_timer(hdev, ev->ncmd);
--
2.37.1
This is automated email and please do not reply to this email!
Dear submitter,
Thank you for submitting the patches to the linux bluetooth mailing list.
This is a CI test results with your patch series:
PW Link:https://patchwork.kernel.org/project/bluetooth/list/?series=666875
---Test result---
Test Summary:
CheckPatch FAIL 1.29 seconds
GitLint PASS 0.79 seconds
SubjectPrefix PASS 0.66 seconds
BuildKernel PASS 35.33 seconds
BuildKernel32 PASS 30.56 seconds
Incremental Build with patchesPASS 43.89 seconds
TestRunner: Setup PASS 506.66 seconds
TestRunner: l2cap-tester PASS 17.73 seconds
TestRunner: bnep-tester PASS 6.90 seconds
TestRunner: mgmt-tester PASS 106.74 seconds
TestRunner: rfcomm-tester PASS 10.39 seconds
TestRunner: sco-tester PASS 10.24 seconds
TestRunner: smp-tester PASS 10.17 seconds
TestRunner: userchan-tester PASS 7.09 seconds
Details
##############################
Test: CheckPatch - FAIL - 1.29 seconds
Run checkpatch.pl script with rule in .checkpatch.conf
[v2] Bluetooth: hci_event: Fix vendor (unknown) opcode status handling\ERROR:GIT_COMMIT_ID: Please use git commit description style 'commit <12+ chars of sha1> ("<title line>")' - ie: 'Commit fatal: unsaf ("ace/src' is owned by someone else)")'
#68:
Commit c8992cffbe74 ("Bluetooth: hci_event: Use of a function table to
handle Command Complete") was (presumably) meant to only refactor things
total: 1 errors, 0 warnings, 0 checks, 26 lines checked
NOTE: For some of the reported defects, checkpatch may be able to
mechanically convert to the typical style using --fix or --fix-inplace.
/github/workspace/src/12941385.patch has style problems, please review.
NOTE: Ignored message types: UNKNOWN_COMMIT_ID
NOTE: If any of the errors are false positives, please report
them to the maintainer, see CHECKPATCH in MAINTAINERS.
---
Regards,
Linux Bluetooth
Hi Hans,
On Thu, Aug 11, 2022 at 5:01 AM Hans de Goede <[email protected]> wrote:
>
> Commit c8992cffbe74 ("Bluetooth: hci_event: Use of a function table to
> handle Command Complete") was (presumably) meant to only refactor things
> without any functional changes.
>
> But it does have one undesirable side-effect, before *status would always
> be set to skb->data[0] and it might be overridden by some of the opcode
> specific handling. While now it always set by the opcode specific handlers.
> This means that if the opcode is not known *status does not get set any
> more at all!
>
> This behavior change has broken bluetooth support for BCM4343A0 HCIs,
> the hci_bcm.c code tries to configure UART attached HCIs at a higher
> baudraute using vendor specific opcodes. The BCM4343A0 does not
> support this and this used to simply fail:
>
> [ 25.646442] Bluetooth: hci0: BCM: failed to write clock (-56)
> [ 25.646481] Bluetooth: hci0: Failed to set baudrate
>
> After which things would continue with the initial baudraute. But now
> that hci_cmd_complete_evt() no longer sets status for unknown opcodes
> *status is left at 0. This causes the hci_bcm.c code to think the baudraute
> has been changed on the HCI side and to also adjust the UART baudrate,
> after which communication with the HCI is broken, leading to:
>
> [ 28.579042] Bluetooth: hci0: command 0x0c03 tx timeout
> [ 36.961601] Bluetooth: hci0: BCM: Reset failed (-110)
>
> And non working bluetooth. Fix this by restoring the previous
> default "*status = skb->data[0]" handling for unknown opcodes.
>
> Fixes: c8992cffbe74 ("Bluetooth: hci_event: Use of a function table to handle Command Complete")
> Cc: Luiz Augusto von Dentz <[email protected]>
> Signed-off-by: Hans de Goede <[email protected]>
> ---
> Changes in v2:
> - Add a comment that byte 0 containing the status is not guaranteed
> by the Bluetooth specification
> ---
> net/bluetooth/hci_event.c | 20 ++++++++++++++++++++
> 1 file changed, 20 insertions(+)
>
> diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
> index af17dfb20e01..eb43afd5549a 100644
> --- a/net/bluetooth/hci_event.c
> +++ b/net/bluetooth/hci_event.c
> @@ -3996,6 +3996,26 @@ static void hci_cmd_complete_evt(struct hci_dev *hdev, void *data,
> break;
> }
> }
> + if (i == ARRAY_SIZE(hci_cc_table)) {
> + /* Unknown opcode, assume byte 0 contains the status, so
> + * that e.g. __hci_cmd_sync() properly returns errors
> + * for vendor specific commands send by HCI drivers.
> + *
> + * Note that the specification does not specify that
> + * byte 0 is the status:
> + *
> + * BLUETOOTH CORE SPECIFICATION Version 5.3 | Vol 4, Part E
> + * page 2189:
> + *
> + * Return_Parameters:
> + * Size: Depends on command
> + *
> + * For now using byte 0 seems to work fine, but in the future
> + * this may need to be updated so that drivers using vendor
> + * commands can specify their own completion handler.
> + */
> + *status = skb->data[0];
> + }
>
> handle_cmd_cnt_and_timer(hdev, ev->ncmd);
>
> --
> 2.37.1
Not sure why CI bot didn't respond to the list but this patch was
already applied yesterday:
https://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth-next.git/commit/?id=84a0a27ea39a9caed74d80a78666a91a9ea5e12b
--
Luiz Augusto von Dentz
Hi Luiz,
On 8/11/22 22:27, Luiz Augusto von Dentz wrote:
> Hi Hans,
>
> On Thu, Aug 11, 2022 at 5:01 AM Hans de Goede <[email protected]> wrote:
>>
>> Commit c8992cffbe74 ("Bluetooth: hci_event: Use of a function table to
>> handle Command Complete") was (presumably) meant to only refactor things
>> without any functional changes.
>>
>> But it does have one undesirable side-effect, before *status would always
>> be set to skb->data[0] and it might be overridden by some of the opcode
>> specific handling. While now it always set by the opcode specific handlers.
>> This means that if the opcode is not known *status does not get set any
>> more at all!
>>
>> This behavior change has broken bluetooth support for BCM4343A0 HCIs,
>> the hci_bcm.c code tries to configure UART attached HCIs at a higher
>> baudraute using vendor specific opcodes. The BCM4343A0 does not
>> support this and this used to simply fail:
>>
>> [ 25.646442] Bluetooth: hci0: BCM: failed to write clock (-56)
>> [ 25.646481] Bluetooth: hci0: Failed to set baudrate
>>
>> After which things would continue with the initial baudraute. But now
>> that hci_cmd_complete_evt() no longer sets status for unknown opcodes
>> *status is left at 0. This causes the hci_bcm.c code to think the baudraute
>> has been changed on the HCI side and to also adjust the UART baudrate,
>> after which communication with the HCI is broken, leading to:
>>
>> [ 28.579042] Bluetooth: hci0: command 0x0c03 tx timeout
>> [ 36.961601] Bluetooth: hci0: BCM: Reset failed (-110)
>>
>> And non working bluetooth. Fix this by restoring the previous
>> default "*status = skb->data[0]" handling for unknown opcodes.
>>
>> Fixes: c8992cffbe74 ("Bluetooth: hci_event: Use of a function table to handle Command Complete")
>> Cc: Luiz Augusto von Dentz <[email protected]>
>> Signed-off-by: Hans de Goede <[email protected]>
>> ---
>> Changes in v2:
>> - Add a comment that byte 0 containing the status is not guaranteed
>> by the Bluetooth specification
>> ---
>> net/bluetooth/hci_event.c | 20 ++++++++++++++++++++
>> 1 file changed, 20 insertions(+)
>>
>> diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
>> index af17dfb20e01..eb43afd5549a 100644
>> --- a/net/bluetooth/hci_event.c
>> +++ b/net/bluetooth/hci_event.c
>> @@ -3996,6 +3996,26 @@ static void hci_cmd_complete_evt(struct hci_dev *hdev, void *data,
>> break;
>> }
>> }
>> + if (i == ARRAY_SIZE(hci_cc_table)) {
>> + /* Unknown opcode, assume byte 0 contains the status, so
>> + * that e.g. __hci_cmd_sync() properly returns errors
>> + * for vendor specific commands send by HCI drivers.
>> + *
>> + * Note that the specification does not specify that
>> + * byte 0 is the status:
>> + *
>> + * BLUETOOTH CORE SPECIFICATION Version 5.3 | Vol 4, Part E
>> + * page 2189:
>> + *
>> + * Return_Parameters:
>> + * Size: Depends on command
>> + *
>> + * For now using byte 0 seems to work fine, but in the future
>> + * this may need to be updated so that drivers using vendor
>> + * commands can specify their own completion handler.
>> + */
>> + *status = skb->data[0];
>> + }
>>
>> handle_cmd_cnt_and_timer(hdev, ev->ncmd);
>>
>> --
>> 2.37.1
>
> Not sure why CI bot didn't respond to the list but this patch was
> already applied yesterday:
>
> https://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth-next.git/commit/?id=84a0a27ea39a9caed74d80a78666a91a9ea5e12b
Great, thank you.
Regards,
Hans