linux-kernel - Re: [PATCH v4] rtw88: Disable PCIe ASPM while doing NAPI poll on 8821CE

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <CAPpJ_ecgPDniiBWnZLfDuQSiW4rvHJ1f4++SsZ3=aTjy_B0Fjg@mail.gmail.com>
Date:   Thu, 16 Dec 2021 10:46:16 +0800
From:   Jian-Hong Pan <jhp@...lessos.org>
To:     Pkshih <pkshih@...ltek.com>
Cc:     "kai.heng.feng@...onical.com" <kai.heng.feng@...onical.com>,
        "tony0620emma@...il.com" <tony0620emma@...il.com>,
        "davem@...emloft.net" <davem@...emloft.net>,
        "jian-hong@...lessm.com" <jian-hong@...lessm.com>,
        "kvalo@...eaurora.org" <kvalo@...eaurora.org>,
        Bernie Huang <phhuang@...ltek.com>,
        "linux-wireless@...r.kernel.org" <linux-wireless@...r.kernel.org>,
        "netdev@...r.kernel.org" <netdev@...r.kernel.org>,
        "kuba@...nel.org" <kuba@...nel.org>,
        "briannorris@...omium.org" <briannorris@...omium.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        linux@...lessos.org
Subject: Re: [PATCH v4] rtw88: Disable PCIe ASPM while doing NAPI poll on 8821CE

Pkshih <pkshih@...ltek.com> 於 2021年12月15日 週三 下午8:23寫道：
>
> On Wed, 2021-12-15 at 19:46 +0800, Kai-Heng Feng wrote:
> > Many Intel based platforms face system random freeze after commit
> > 9e2fd29864c5 ("rtw88: add napi support").
> >
> > The commit itself shouldn't be the culprit. My guess is that the 8821CE
> > only leaves ASPM L1 for a short period when IRQ is raised. Since IRQ is
> > masked during NAPI polling, the PCIe link stays at L1 and makes RX DMA
> > extremely slow. Eventually the RX ring becomes messed up:
> > [ 1133.194697] rtw_8821ce 0000:02:00.0: pci bus timeout, check dma status
> >
> > Since the 8821CE hardware may fail to leave ASPM L1, manually do it in
> > the driver to resolve the issue.
> >
> > Fixes: 9e2fd29864c5 ("rtw88: add napi support")
> > Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=215131
> > BugLink: https://bugs.launchpad.net/bugs/1927808
> > Signed-off-by: Kai-Heng Feng <kai.heng.feng@...onical.com>
>
> Reviewed-and-Tested-by: Ping-Ke Shih <pkshih@...ltek.com>

Acked-by: Jian-Hong Pan <jhp@...lessos.org>

> > ---
> > v4:
> >  - Rebase to the right tree.
> >
> > v3:
> >  - Move the module parameter to be part of private struct.
> >  - Ensure link_usage never goes below zero.
> >
> > v2:
> >  - Add default value for module parameter.
> >
> >  drivers/net/wireless/realtek/rtw88/pci.c | 70 +++++++-----------------
> >  drivers/net/wireless/realtek/rtw88/pci.h |  2 +
> >  2 files changed, 21 insertions(+), 51 deletions(-)
> >
> >
>
> [...]
>
>