Re: [PATCH] e1000e: Add error handling for e1e_rphy_locked()

On Mon, Apr 07, 2025 at 11:41:54AM +0800, Wentao Liang wrote:

The e1000_suspend_workarounds_ich8lan() calls e1e_rphy_locked to disable the SMB release, but does not check its return value. A proper implementation can be found in e1000_resume_workarounds_pchlan() from /source/drivers/net/ethernet/intel/e1000e/ich8lan.c.

Add an error check for e1e_rphy_locked(). Log the error message and jump to 'release' label if the e1e_rphy_locked() fails.

Fixes: 2fbe4526e5aa ("e1000e: initial support for i217") Cc: stable@vger.kernel.org # v3.5+ Signed-off-by: Wentao Liang vulab@iscas.ac.cn

---

drivers/net/ethernet/intel/e1000e/ich8lan.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/intel/e1000e/ich8lan.c b/drivers/net/ethernet/intel/e1000e/ich8lan.c index 2f9655cf5dd9..d16e3aa50809 100644 --- a/drivers/net/ethernet/intel/e1000e/ich8lan.c +++ b/drivers/net/ethernet/intel/e1000e/ich8lan.c @@ -5497,7 +5497,11 @@ void e1000_suspend_workarounds_ich8lan(struct e1000_hw *hw) e1e_wphy_locked(hw, I217_SxCTRL, phy_reg); /* Disable the SMB release on LCD reset. */

• 	e1e_rphy_locked(hw, I217_MEMPWR, &phy_reg);
  

• 	ret_val = e1e_rphy_locked(hw, I217_MEMPWR, &phy_reg);
  

• 	if (ret_val) {
  

• 		e_dbg("Fail to Disable the SMB release on LCD reset.");
  

• 		goto release;
  

• 	}
  phy_reg &= ~I217_MEMPWR_DISABLE_SMB_RELEASE;
  e1e_wphy_locked(hw, I217_MEMPWR, phy_reg);
  

  }

Hi,

The next few lines of this function look like this:

/* Enable MTA to reset for Intel Rapid Start Technology * Support */ e1e_rphy_locked(hw, I217_CGFREG, &phy_reg); phy_reg |= I217_CGFREG_ENABLE_MTA_RESET; e1e_wphy_locked(hw, I217_CGFREG, phy_reg);

And I think that to be consistent with e1000_resume_workarounds_pchlan() the return value of the above call to e1e_rphy_locked() should also be checked.

However, I am not at all sure if the current absence of error checking is intended as part of the logic flow, or if these are oversights.

Have you observed any run-time problems with this code?

I would naively expect that the i217 is or was a widely used device. And this code seems to have been around for a well over 10 years in it's current form. Which makes me thing we should tread carefully when changing it.