net: fec: ptp: avoid register access when ipg clock is disabled
Subsystems (3)
PATCH v2 1/1 net: fec: ptp: avoid register access when ipg clock is disabled
When accessing the timecounter register on an i.MX8MQ the kernel hangs. This is only the case when the interface is down. This can be reproduced by reading with 'phc_ctrl eth0 get'.
Like described in the change in 91c0d987a9788dcc5fe26baafd73bf9242b68900 the igp clock is disabled when the interface is down and leads to a system hang.
So we check if the ptp clock status before reading the timecounter register.
---
v2:
- add mutex (thanks to Richard)
drivers/net/ethernet/freescale/fec_ptp.c | 6 ++++++ 1 file changed, 6 insertions(+)
drivers/net/ethernet/freescale/fec_ptp.c +6 -0
@@ -377,9 +377,15 @@ static int fec_ptp_gettime(struct ptp_clock_info *ptp, struct timespec64 *ts)u64 ns;unsigned long flags; +mutex_lock (&fep->ptp_clk_mutex); +/* Check the ptp clock */ +if (!adapter->ptp_clk_on) +mutex_unlock (&fep->ptp_clk_mutex); +return -EINVAL ;spin_lock_irqsave (&adapter->tmreg_lock, flags); ns =timecounter_read (&adapter->tc);spin_unlock_irqrestore (&adapter->tmreg_lock, flags); +mutex_unlock (&fep->ptp_clk_mutex); *ts =ns_to_timespec64 (ns);
Signature · 1 line
2.30.0
kernel test robot
build botThank you for the patch! Yet something to improve:
Hi Heiko,
Thank you for the patch! Yet something to improve:
[auto build test ERROR on net/master]
[also build test ERROR on net-next/master ipvs/master linus/master v5.11 next-20210225] [If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]
url: https://github.com/0day-ci/linux/commits/Heiko-Thiery/net-fec-ptp-avoid-register-access-when-ipg-clock-is-disabled/20210226-050218 base: https://git.kernel.org/pub/scm/linux/kernel/git/davem/net.git 6cf739131a15e4177e58a1b4f2bede9d5da78552 config: mips-randconfig-r013-20210225 (attached as .config) compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project a921aaf789912d981cbb2036bdc91ad7289e1523)
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross
# install mips cross compiling tool for clang build
# apt-get install binutils-mips-linux-gnu
# https://github.com/0day-ci/linux/commit/a7258bb15d947bb808b6209012a56ae993ec6001
git remote add linux-review https://github.com/0day-ci/linux
git fetch --no-tags linux-review Heiko-Thiery/net-fec-ptp-avoid-register-access-when-ipg-clock-is-disabled/20210226-050218 git checkout a7258bb15d947bb808b6209012a56ae993ec6001
# save the attached .config to linux build tree
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=mips
If you fix the issue, kindly add following tag as appropriate
All error/warnings (new ones prefixed by >>):
>> drivers/net/ethernet/freescale/fec_ptp.c:380:14: error: use of undeclared identifier 'fep'
mutex_lock(&fep->ptp_clk_mutex);
^
drivers/net/ethernet/freescale/fec_ptp.c:383:17: error: use of undeclared identifier 'fep'
mutex_unlock(&fep->ptp_clk_mutex);
^
>> drivers/net/ethernet/freescale/fec_ptp.c:384:3: warning: misleading indentation; statement is not part of the previous 'if' [-Wmisleading-indentation]
return -EINVAL;
^
drivers/net/ethernet/freescale/fec_ptp.c:382:2: note: previous statement is here
if (!adapter->ptp_clk_on)
^
drivers/net/ethernet/freescale/fec_ptp.c:388:16: error: use of undeclared identifier 'fep'
mutex_unlock(&fep->ptp_clk_mutex);
^1 warning and 3 errors generated.
vim +/fep +380 drivers/net/ethernet/freescale/fec_ptp.c
364
365 /**
366 * fec_ptp_gettime
367 * @ptp: the ptp clock structure
368 * @ts: timespec structure to hold the current time value
369 *
370 * read the timecounter and return the correct value on ns,
371 * after converting it into a struct timespec.
372 */
373 static int fec_ptp_gettime(struct ptp_clock_info *ptp, struct timespec64 *ts)
374 {
375 struct fec_enet_private *adapter =
376 container_of(ptp, struct fec_enet_private, ptp_caps);
377 u64 ns;
378 unsigned long flags;
379
> 380 mutex_lock(&fep->ptp_clk_mutex); 381 /* Check the ptp clock */ 382 if (!adapter->ptp_clk_on) 383 mutex_unlock(&fep->ptp_clk_mutex); > 384 return -EINVAL;
385 spin_lock_irqsave(&adapter->tmreg_lock, flags);
386 ns = timecounter_read(&adapter->tc);
387 spin_unlock_irqrestore(&adapter->tmreg_lock, flags);
388 mutex_unlock(&fep->ptp_clk_mutex);
389
390 *ts = ns_to_timespec64(ns);
391
392 return 0;
393 }
394
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all(a)lists.01.org