Go to file
Vignesh Raghavendra 47bfc4d128 net: ti: am65-cpsw-nuss: fix RX IRQ state after .ndo_stop()
On TI K3 am64x platform the issue with RX IRQ is observed - it's become
disabled forever after .ndo_stop(). The K3 CPSW driver manipulates RX IRQ
by using standard Linux enable_irq()/disable_irq_nosync() API as there is
no IRQ enable/disable options in CPSW HW itself, as result during
.ndo_stop() following sequence happens

  phy_stop()
  teardown TX/RX channels
  wait for TX tdown complete
  napi_disable(TX)
  clean up TX channels

  (a)

  napi_disable(RX)

At point (a) it's not possible to predict if RX IRQ was triggered or not.
if RX IRQ was triggered then it also not possible to definitely say if RX
NAPI was run or only scheduled and immediately canceled by
napi_disable(RX). Actually the last case causes RX IRQ to be permanently
disabled.

Another observed issue is that RX IRQ enable counter become unbalanced if
(gro_flush_timeout =! 0) while (napi_defer_hard_irqs == 0):

Unbalanced enable for IRQ 44
WARNING: CPU: 0 PID: 10 at ../kernel/irq/manage.c:776 __enable_irq+0x38/0x80
__enable_irq+0x38/0x80
enable_irq+0x54/0xb0
am65_cpsw_nuss_rx_poll+0x2f4/0x368
__napi_poll+0x34/0x1b8
net_rx_action+0xe4/0x220
_stext+0x11c/0x284
run_ksoftirqd+0x4c/0x60

To avoid above issues introduce flag indicating if RX was actually disabled
before enabling it in am65_cpsw_nuss_rx_poll() and restore RX IRQ state in
.ndo_open()

Fixes: 4f7cce2724 ("net: ethernet: ti: am65-cpsw: add support for am64x cpsw3g")
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-06 11:08:57 +01:00
arch Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2021-08-05 15:08:47 -07:00
block block-5.14-2021-07-30 2021-07-30 11:08:12 -07:00
certs Kbuild updates for v5.13 (2nd) 2021-05-08 10:00:11 -07:00
crypto Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2021-07-09 11:00:44 -07:00
Documentation Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2021-08-05 15:08:47 -07:00
drivers net: ti: am65-cpsw-nuss: fix RX IRQ state after .ndo_stop() 2021-08-06 11:08:57 +01:00
fs pipe: increase minimum default pipe size to 2 pages 2021-08-05 10:30:47 -07:00
include Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2021-08-05 15:08:47 -07:00
init xsurf100: drop include of lib8390.c 2021-08-03 13:05:26 +01:00
ipc Merge branch 'akpm' (patches from Andrew) 2021-07-02 12:08:10 -07:00
kernel Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2021-08-05 15:08:47 -07:00
lib Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next 2021-07-31 11:23:26 -07:00
LICENSES LICENSES/dual/CC-BY-4.0: Git rid of "smart quotes" 2021-07-15 06:31:24 -06:00
mm Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2021-07-31 09:14:46 -07:00
net ethtool: return error from ethnl_ops_begin if dev is NULL 2021-08-06 10:39:04 +01:00
samples samples: bpf: Add the omitted xdp samples to .gitignore 2021-07-27 11:15:09 -07:00
scripts Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2021-08-05 15:08:47 -07:00
security Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2021-08-05 15:08:47 -07:00
sound sound fixes for 5.14-rc3 2021-07-23 09:58:23 -07:00
tools Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2021-08-05 15:08:47 -07:00
usr .gitignore: prefix local generated files with a slash 2021-05-02 00:43:35 +09:00
virt KVM: Do not leak memory for duplicate debugfs directories 2021-08-04 06:02:03 -04:00
.clang-format clang-format: Update with the latest for_each macro list 2021-05-12 23:32:39 +02:00
.cocciconfig
.get_maintainer.ignore Opt out of scripts/get_maintainer.pl 2019-05-16 10:53:40 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore .gitignore: ignore only top-level modules.builtin 2021-05-02 00:43:35 +09:00
.mailmap m68k updates for v5.14 2021-06-28 14:01:03 -07:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: move Murali Karicheri to credits 2021-04-29 15:47:30 -07:00
Kbuild kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2021-07-31 09:14:46 -07:00
Makefile Various tracing fixes: 2021-08-05 11:53:34 -07:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.