diff mbox series

[v2,2/2] ath10k: start recovery process when payload length exceeds max htc length for sdio

Message ID 20191225120002.11163-3-wgong@codeaurora.org (mailing list archive)
State Changes Requested
Delegated to: Kalle Valo
Headers show
Series start recovery process when payload length overflow for sdio | expand

Commit Message

Wen Gong Dec. 25, 2019, noon UTC
When simulate random transfer fail for sdio write and read, it happened
"payload length exceeds max htc length" and recovery later sometimes.

Test steps:
1. Add config and update kernel:
CONFIG_FAIL_MMC_REQUEST=y
CONFIG_FAULT_INJECTION=y
CONFIG_FAULT_INJECTION_DEBUG_FS=y

2. Run simulate fail:
cd /sys/kernel/debug/mmc1/fail_mmc_request
echo 10 > probability
echo 10 > times # repeat until hitting issues

3. It happened payload length exceeds max htc length.
[  199.935506] ath10k_sdio mmc1:0001:1: payload length 57005 exceeds max htc length: 4088
....
[  264.990191] ath10k_sdio mmc1:0001:1: payload length 57005 exceeds max htc length: 4088

4. after some time, such as 60 seconds, it start recovery which triggered
by wmi command timeout for periodic scan.
[  269.229232] ieee80211 phy0: Hardware restart was requested
[  269.734693] ath10k_sdio mmc1:0001:1: device successfully recovered

The simulate fail of sdio is not a real sdio transter fail, it only
set an error status in mmc_should_fail_request after the transfer end,
actually the transfer is success, then sdio_io_rw_ext_helper will
return error status and stop transfer the left data. For example,
the really RX len is 286 bytes, then it will split to 2 blocks in
sdio_io_rw_ext_helper, one is 256 bytes, left is 30 bytes, if the
first 256 bytes get an error status by mmc_should_fail_request,then
the left 30 bytes will not read in this RX operation. Then when the
next RX arrive, the left 30 bytes will be considered as the header
of the read, the top 4 bytes of the 30 bytes will be considered as
lookaheads, but actually the 4 bytes is not the lookaheads, so the len
from this lookaheads is not correct, it exceeds max htc length 4088
sometimes. When happened exceeds, the buffer chain is not matched between
firmware and ath10k, then it need to start recovery ASAP. Recently then
recovery will be started by wmi command timeout, but it will be long time
later, for example, it is 60+ seconds later from the periodic scan, if
it does not have periodic scan, it will be longer.

Start recovery when it happened "payload length exceeds max htc length"
will be reasonable.

This patch only effect sdio chips.

Tested with QCA6174 SDIO with firmware WLAN.RMH.4.4.1-00029.

Signed-off-by: Wen Gong <wgong@codeaurora.org>
---
 drivers/net/wireless/ath/ath10k/sdio.c | 6 ++++++
 1 file changed, 6 insertions(+)

Comments

Justin Capella Dec. 25, 2019, 10:56 p.m. UTC | #1
Does the SDIO bus require addresses to be word aligned like the PCI
bus does? I'm thinking of how netdev alloc uses skb_push to ensure
that the payload is aligned.


>> if (ar->state == ATH10K_STATE_ON)

What about the other STATEs: RESTARTED/ING

The value you mentioned 57005, is 0xDEAD is that a special case?
Perhaps a result of fw crash? Maybe a lookahead gone wong? I see its
the WMI PEER ALIVE/DEAD indicator but I'm not sure why it would be
trailer of the other

On Wed, Dec 25, 2019 at 4:01 AM Wen Gong <wgong@codeaurora.org> wrote:
>
> When simulate random transfer fail for sdio write and read, it happened
> "payload length exceeds max htc length" and recovery later sometimes.
>
> Test steps:
> 1. Add config and update kernel:
> CONFIG_FAIL_MMC_REQUEST=y
> CONFIG_FAULT_INJECTION=y
> CONFIG_FAULT_INJECTION_DEBUG_FS=y
>
> 2. Run simulate fail:
> cd /sys/kernel/debug/mmc1/fail_mmc_request
> echo 10 > probability
> echo 10 > times # repeat until hitting issues
>
> 3. It happened payload length exceeds max htc length.
> [  199.935506] ath10k_sdio mmc1:0001:1: payload length 57005 exceeds max htc length: 4088
> ....
> [  264.990191] ath10k_sdio mmc1:0001:1: payload length 57005 exceeds max htc length: 4088
>
> 4. after some time, such as 60 seconds, it start recovery which triggered
> by wmi command timeout for periodic scan.
> [  269.229232] ieee80211 phy0: Hardware restart was requested
> [  269.734693] ath10k_sdio mmc1:0001:1: device successfully recovered
>
> The simulate fail of sdio is not a real sdio transter fail, it only
> set an error status in mmc_should_fail_request after the transfer end,
> actually the transfer is success, then sdio_io_rw_ext_helper will
> return error status and stop transfer the left data. For example,
> the really RX len is 286 bytes, then it will split to 2 blocks in
> sdio_io_rw_ext_helper, one is 256 bytes, left is 30 bytes, if the
> first 256 bytes get an error status by mmc_should_fail_request,then
> the left 30 bytes will not read in this RX operation. Then when the
> next RX arrive, the left 30 bytes will be considered as the header
> of the read, the top 4 bytes of the 30 bytes will be considered as
> lookaheads, but actually the 4 bytes is not the lookaheads, so the len
> from this lookaheads is not correct, it exceeds max htc length 4088
> sometimes. When happened exceeds, the buffer chain is not matched between
> firmware and ath10k, then it need to start recovery ASAP. Recently then
> recovery will be started by wmi command timeout, but it will be long time
> later, for example, it is 60+ seconds later from the periodic scan, if
> it does not have periodic scan, it will be longer.
>
> Start recovery when it happened "payload length exceeds max htc length"
> will be reasonable.
>
> This patch only effect sdio chips.
>
> Tested with QCA6174 SDIO with firmware WLAN.RMH.4.4.1-00029.
>
> Signed-off-by: Wen Gong <wgong@codeaurora.org>
> ---
>  drivers/net/wireless/ath/ath10k/sdio.c | 6 ++++++
>  1 file changed, 6 insertions(+)
>
> diff --git a/drivers/net/wireless/ath/ath10k/sdio.c b/drivers/net/wireless/ath/ath10k/sdio.c
> index 7b894dcaad2e..78f431609493 100644
> --- a/drivers/net/wireless/ath/ath10k/sdio.c
> +++ b/drivers/net/wireless/ath/ath10k/sdio.c
> @@ -557,6 +557,12 @@ static int ath10k_sdio_mbox_rx_alloc(struct ath10k *ar,
>                                     le16_to_cpu(htc_hdr->len),
>                                     ATH10K_HTC_MBOX_MAX_PAYLOAD_LENGTH);
>                         ret = -ENOMEM;
> +
> +                       if (ar->state == ATH10K_STATE_ON) {
> +                               queue_work(ar->workqueue, &ar->restart_work);
> +                               ath10k_warn(ar, "exceeds length, start recovery\n");
> +                       }
> +
>                         goto err;
>                 }
>
> --
> 2.23.0
Wen Gong Jan. 2, 2020, 4:50 a.m. UTC | #2
On 2019-12-25 14:56, Justin Capella wrote:
> Does the SDIO bus require addresses to be word aligned like the PCI
> bus does? I'm thinking of how netdev alloc uses skb_push to ensure
> that the payload is aligned.
> 
> 
>>> if (ar->state == ATH10K_STATE_ON)
> 
> What about the other STATEs: RESTARTED/ING
> 
> The value you mentioned 57005, is 0xDEAD is that a special case?
> Perhaps a result of fw crash? Maybe a lookahead gone wong? I see its
> the WMI PEER ALIVE/DEAD indicator but I'm not sure why it would be
> trailer of the other
> 
i have removed "if (ar->state == ATH10K_STATE_ON)"
and v3 sent:
patch v3:
https://patchwork.kernel.org/patch/11313853/
https://patchwork.kernel.org/patch/11313859/

>> 2.23.0
diff mbox series

Patch

diff --git a/drivers/net/wireless/ath/ath10k/sdio.c b/drivers/net/wireless/ath/ath10k/sdio.c
index 7b894dcaad2e..78f431609493 100644
--- a/drivers/net/wireless/ath/ath10k/sdio.c
+++ b/drivers/net/wireless/ath/ath10k/sdio.c
@@ -557,6 +557,12 @@  static int ath10k_sdio_mbox_rx_alloc(struct ath10k *ar,
 				    le16_to_cpu(htc_hdr->len),
 				    ATH10K_HTC_MBOX_MAX_PAYLOAD_LENGTH);
 			ret = -ENOMEM;
+
+			if (ar->state == ATH10K_STATE_ON) {
+				queue_work(ar->workqueue, &ar->restart_work);
+				ath10k_warn(ar, "exceeds length, start recovery\n");
+			}
+
 			goto err;
 		}