Re: [PATCH 0/4] rtw88: Four fixes found while working on SDIO support

From: Larry Finger
Date: Thu Dec 29 2022 - 12:41:26 EST


On 12/29/22 06:48, Martin Blumenstingl wrote:
This series consists of three patches which are fixing existing
behavior (meaning: it either affects PCIe or USB or both) in the rtw88
driver.

The first change adds the packed attribute to the eFuse structs. This
was spotted by Ping-Ke while reviewing the SDIO support patches from
[0].

The remaining three changes relate to locking (barrier hold) problems.
We previously had discussed patches for this for SDIO support, but the
problem never ocurred while testing USB cards. It turns out that these
are still needed and I think that they also fix the same problems for
USB users (it's not clear how often it happens there though).

The issue fixed by the second and third patches have been spotted by a
user who tested rtw88 SDIO support. Everything is working fine for him
but there are warnings [1] and [2] in the kernel log stating "Voluntary
context switch within RCU read-side critical section!".

The solution in the third and fourth patch was actually suggested by
Ping-Ke in [3]. Thanks again!

These fixes are indepdent of my other series adding SDIO support to the
rtw88 driver, meaning they can be added to the wireless driver tree on
top of Linux 6.2-rc1 or linux-next.


Changes since v1 at [4]:
- Keep the u8 bitfields in patch 1 but split the res2 field into res2_1
and res2_2 as suggested by Ping-Ke
- Added Ping-Ke's reviewed-by to patches 2-4 - thank you!
- Added a paragraph in the cover-letter to avoid confusion whether
these patches depend on the rtw88 SDIO support series


[0] https://lore.kernel.org/linux-wireless/695c976e02ed44a2b2345a3ceb226fc4@xxxxxxxxxxx/
[1] https://github.com/LibreELEC/LibreELEC.tv/pull/7301#issuecomment-1366421445
[2] https://github.com/LibreELEC/LibreELEC.tv/pull/7301#issuecomment-1366610249
[3] https://lore.kernel.org/lkml/e0aa1ba4336ab130712e1fcb425e6fd0adca4145.camel@xxxxxxxxxxx/


Martin Blumenstingl (4):
rtw88: Add packed attribute to the eFuse structs
rtw88: Configure the registers from rtw_bf_assoc() outside the RCU
lock
rtw88: Use rtw_iterate_vifs() for rtw_vif_watch_dog_iter()
rtw88: Use non-atomic rtw_iterate_stas() in rtw_ra_mask_info_update()

drivers/net/wireless/realtek/rtw88/bf.c | 13 +++++++------
drivers/net/wireless/realtek/rtw88/mac80211.c | 4 +++-
drivers/net/wireless/realtek/rtw88/main.c | 6 ++++--
drivers/net/wireless/realtek/rtw88/main.h | 6 +++---
drivers/net/wireless/realtek/rtw88/rtw8723d.h | 6 +++---
drivers/net/wireless/realtek/rtw88/rtw8821c.h | 9 +++++----
drivers/net/wireless/realtek/rtw88/rtw8822b.h | 9 +++++----
drivers/net/wireless/realtek/rtw88/rtw8822c.h | 9 +++++----
8 files changed, 35 insertions(+), 27 deletions(-)


Martin,

I do not feel qualified to review these contributions, but I have some suggestions.

The first is that the subject should start with wifi: rtw88: .... That is a fairly recent change that you likely did not catch.

My second comment is that changed patches should have a version number to identify that they are new patches. You can generate the correct form using the "-v N" option in 'git format-email'. Once you have generated the patches, you should then edit them to indicate what change was made to each patch in the various versions. Such explanations should go below the --- following the Signed-off-by line, and end with another ---. With these additions, the community, and more importantly Kalle, can keep track of the various versions, and know what reviewer's comments have been addressed.

I know of several people that have asked about SDIO versions of these drivers. They will be pleased to see them become available.

Larry