[PATCH 5.15 047/124] net: stmmac: Use readl_poll_timeout_atomic() in atomic state

Greg Kroah-Hartman
2022-04-26T09:14:40Z

From: Kevin Hao <haokexin@gmail.com>

[ Upstream commit 234901de2bc6847eaa0aeb4aba62c31ffb8d3ad6 ]

The init_systime() may be invoked in atomic state. We have observed the
following call trace when running "phc_ctl /dev/ptp0 set" on a Intel
Agilex board.
BUG: sleeping function called from invalid context at drivers/net/ethernet/stmicro/stmmac/stmmac_hwtstamp.c:74
in_atomic(): 1, irqs_disabled(): 128, non_block: 0, pid: 381, name: phc_ctl
preempt_count: 1, expected: 0
RCU nest depth: 0, expected: 0
Preemption disabled at:
[<ffff80000892ef78>] stmmac_set_time+0x34/0x8c
CPU: 2 PID: 381 Comm: phc_ctl Not tainted 5.18.0-rc2-next-20220414-yocto-standard+ #567
Hardware name: SoCFPGA Agilex SoCDK (DT)
Call trace:
dump_backtrace.part.0+0xc4/0xd0
show_stack+0x24/0x40
dump_stack_lvl+0x7c/0xa0
dump_stack+0x18/0x34
__might_resched+0x154/0x1c0
__might_sleep+0x58/0x90
init_systime+0x78/0x120
stmmac_set_time+0x64/0x8c
ptp_clock_settime+0x60/0x9c
pc_clock_settime+0x6c/0xc0
__arm64_sys_clock_settime+0x88/0xf0
invoke_syscall+0x5c/0x130
el0_svc_common.constprop.0+0x4c/0x100
do_el0_svc+0x7c/0xa0
el0_svc+0x58/0xcc
el0t_64_sync_handler+0xa4/0x130
el0t_64_sync+0x18c/0x190

So we should use readl_poll_timeout_atomic() here instead of
readl_poll_timeout().

Also adjust the delay time to 10us to fix a "__bad_udelay" build error
reported by "kernel test robot <lkp@intel.com>". I have tested this on
Intel Agilex and NXP S32G boards, there is no delay needed at all.
So the 10us delay should be long enough for most cases.

Fixes: ff8ed737860e ("net: stmmac: use readl_poll_timeout() function in init_systime()")
Signed-off-by: Kevin Hao <haokexin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/ethernet/stmicro/stmmac/stmmac_hwtstamp.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_hwtstamp.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_hwtstamp.c
index a7ec9f4d46ce..d68ef72dcdde 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_hwtstamp.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_hwtstamp.c
@@ -71,9 +71,9 @@ static int init_systime(void __iomem *ioaddr, u32 sec, u32 nsec)
writel(value, ioaddr + PTP_TCR);

/* wait for present system time initialize to complete */
- return readl_poll_timeout(ioaddr + PTP_TCR, value,
+ return readl_poll_timeout_atomic(ioaddr + PTP_TCR, value,
!(value & PTP_TCR_TSINIT),
- 10000, 100000);
+ 10, 100000);
}

static int config_addend(void __iomem *ioaddr, u32 addend)
--
2.35.1