net: stmmac: fix incorrect rxq|txq_stats reference
authorJisheng Zhang <jszhang@kernel.org>
Sun, 17 Sep 2023 16:53:28 +0000 (00:53 +0800)
committerPaolo Abeni <pabeni@redhat.com>
Tue, 19 Sep 2023 08:21:15 +0000 (10:21 +0200)
commit8070274b472e2e9f5f67a990f5e697634c415708
treec7f66a2c075114012e973fd6dfbc4884fae6f9e7
parent6dab9dd6490791b8038b0622827ecd418439c1a3
net: stmmac: fix incorrect rxq|txq_stats reference

commit 133466c3bbe1 ("net: stmmac: use per-queue 64 bit statistics
where necessary") caused one regression as found by Uwe, the backtrace
looks like:

INFO: trying to register non-static key.
The code is fine but needs lockdep annotation, or maybe
you didn't initialize this object before use?
turning off the locking correctness validator.
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 6.5.0-rc1-00449-g133466c3bbe1-dirty #21
Hardware name: STM32 (Device Tree Support)
 unwind_backtrace from show_stack+0x18/0x1c
 show_stack from dump_stack_lvl+0x60/0x90
 dump_stack_lvl from register_lock_class+0x98c/0x99c
 register_lock_class from __lock_acquire+0x74/0x293c
 __lock_acquire from lock_acquire+0x134/0x398
 lock_acquire from stmmac_get_stats64+0x2ac/0x2fc
 stmmac_get_stats64 from dev_get_stats+0x44/0x130
 dev_get_stats from rtnl_fill_stats+0x38/0x120
 rtnl_fill_stats from rtnl_fill_ifinfo+0x834/0x17f4
 rtnl_fill_ifinfo from rtmsg_ifinfo_build_skb+0xc0/0x144
 rtmsg_ifinfo_build_skb from rtmsg_ifinfo+0x50/0x88
 rtmsg_ifinfo from __dev_notify_flags+0xc0/0xec
 __dev_notify_flags from dev_change_flags+0x50/0x5c
 dev_change_flags from ip_auto_config+0x2f4/0x1260
 ip_auto_config from do_one_initcall+0x70/0x35c
 do_one_initcall from kernel_init_freeable+0x2ac/0x308
 kernel_init_freeable from kernel_init+0x1c/0x138
 kernel_init from ret_from_fork+0x14/0x2c

The reason is the rxq|txq_stats structures are not what expected
because stmmac_open() -> __stmmac_open() the structure is overwritten
by "memcpy(&priv->dma_conf, dma_conf, sizeof(*dma_conf));"
This causes the well initialized syncp member of rxq|txq_stats is
overwritten unexpectedly as pointed out by Johannes and Uwe.

Fix this issue by moving rxq|txq_stats back to stmmac_extra_stats. For
SMP cache friendly, we also mark stmmac_txq_stats and stmmac_rxq_stats
as ____cacheline_aligned_in_smp.

Fixes: 133466c3bbe1 ("net: stmmac: use per-queue 64 bit statistics where necessary")
Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
Reported-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Tested-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20230917165328.3403-1-jszhang@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
drivers/net/ethernet/stmicro/stmmac/common.h
drivers/net/ethernet/stmicro/stmmac/dwmac-sun8i.c
drivers/net/ethernet/stmicro/stmmac/dwmac4_lib.c
drivers/net/ethernet/stmicro/stmmac/dwmac_lib.c
drivers/net/ethernet/stmicro/stmmac/dwxgmac2_dma.c
drivers/net/ethernet/stmicro/stmmac/stmmac.h
drivers/net/ethernet/stmicro/stmmac/stmmac_ethtool.c
drivers/net/ethernet/stmicro/stmmac/stmmac_main.c