[PATCH net 0/4][pull request] Intel Wired LAN Driver Updates 2022-04-13

This series contains updates to igc and e1000e drivers.

Sasha removes waiting for hardware semaphore as it could cause an
infinite loop and changes usleep_range() calls done under atomic
context to udelay() for igc. For e1000e, he changes some variables from
u16 to u32 to prevent possible overflow of values.

Vinicius disables PTM when going to suspend as it is causing hang issues
on some platforms for igc.

The following are changes since commit ef27324e2cb7bb24542d6cb2571740eefe6b00dc:
  nfc: nci: add flush_workqueue to prevent uaf
and are available in the git repository at:
  git://git.kernel.org/pub/scm/linux/kernel/git/tnguy/net-queue 1GbE

Sasha Neftin (3):
  igc: Fix infinite loop in release_swfw_sync
  igc: Fix BUG: scheduling while atomic
  e1000e: Fix possible overflow in LTR decoding

Vinicius Costa Gomes (1):
  igc: Fix suspending when PTM is active

 drivers/net/ethernet/intel/e1000e/ich8lan.c |  4 ++--
 drivers/net/ethernet/intel/igc/igc_i225.c   | 11 +++++++++--
 drivers/net/ethernet/intel/igc/igc_phy.c    |  4 ++--
 drivers/net/ethernet/intel/igc/igc_ptp.c    | 15 ++++++++++++++-
 4 files changed, 27 insertions(+), 7 deletions(-)

-- 
2.31.1

From: Sasha Neftin <redacted>

When we decode the latency and the max_latency, u16 value may not fit
the required size and could lead to the wrong LTR representation.

Scaling is represented as:
scale 0 - 1         (2^(5*0)) = 2^0
scale 1 - 32        (2^(5 *1))= 2^5
scale 2 - 1024      (2^(5 *2)) =2^10
scale 3 - 32768     (2^(5 *3)) =2^15
scale 4 - 1048576   (2^(5 *4)) = 2^20
scale 5 - 33554432  (2^(5 *4)) = 2^25
scale 4 and scale 5 required 20 and 25 bits respectively.
scale 6 reserved.

Replace the u16 type with the u32 type and allow corrected LTR
representation.

Cc: <redacted>
Fixes: 44a13a5d99c7 ("e1000e: Fix the max snoop/no-snoop latency for 10M")
Reported-by: James Hutchinson <redacted>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=215689
Suggested-by: Dima Ruinskiy <redacted>
Signed-off-by: Sasha Neftin <redacted>
Tested-by: Naama Meir <redacted>
Tested-by: James Hutchinson <redacted>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
---
 drivers/net/ethernet/intel/e1000e/ich8lan.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/intel/e1000e/ich8lan.c b/drivers/net/ethernet/intel/e1000e/ich8lan.c
index d60e2016d03c..e6c8e6d5234f 100644
--- a/drivers/net/ethernet/intel/e1000e/ich8lan.c
+++ b/drivers/net/ethernet/intel/e1000e/ich8lan.c

@@ -1009,8 +1009,8 @@ static s32 e1000_platform_pm_pch_lpt(struct e1000_hw *hw, bool link)
 {
 	u32 reg = link << (E1000_LTRV_REQ_SHIFT + E1000_LTRV_NOSNOOP_SHIFT) |
 	    link << E1000_LTRV_REQ_SHIFT | E1000_LTRV_SEND;
-	u16 max_ltr_enc_d = 0;	/* maximum LTR decoded by platform */
-	u16 lat_enc_d = 0;	/* latency decoded */
+	u32 max_ltr_enc_d = 0;	/* maximum LTR decoded by platform */
+	u32 lat_enc_d = 0;	/* latency decoded */
 	u16 lat_enc = 0;	/* latency encoded */
 
 	if (link) {

-- 
2.31.1

From: Sasha Neftin <redacted>

Replace usleep_range() method with udelay() method to allow atomic contexts
in low-level MDIO access functions.

The following issue can be seen by doing the following:
$ modprobe -r bonding
$ modprobe -v bonding max_bonds=1 mode=1 miimon=100 use_carrier=0
$ ip link set bond0 up
$ ifenslave bond0 eth0 eth1

[  982.357308] BUG: scheduling while atomic: kworker/u64:0/9/0x00000002
[  982.364431] INFO: lockdep is turned off.
[  982.368824] Modules linked in: bonding sctp ip6_udp_tunnel udp_tunnel mlx4_ib ib_uverbs ib_core mlx4_en mlx4_core nfp tls sunrpc intel_rapl_msr iTCO_wdt iTCO_vendor_support mxm_wmi dcdbas intel_rapl_common sb_edac x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel kvm irqbypass crct10dif_pclmul crc32_pclmul ghash_clmulni_intel rapl intel_cstate intel_uncore pcspkr lpc_ich mei_me ipmi_ssif mei ipmi_si ipmi_devintf ipmi_msghandler wmi acpi_power_meter xfs libcrc32c sr_mod cdrom sd_mod t10_pi sg mgag200 drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops drm ahci libahci crc32c_intel libata i2c_algo_bit tg3 megaraid_sas igc dm_mirror dm_region_hash dm_log dm_mod [last unloaded: bonding]
[  982.437941] CPU: 25 PID: 9 Comm: kworker/u64:0 Kdump: loaded Tainted: G        W        --------- -  - 4.18.0-348.el8.x86_64+debug #1
[  982.451333] Hardware name: Dell Inc. PowerEdge R730/0H21J3, BIOS 2.7.0 12/005/2017
[  982.459791] Workqueue: bond0 bond_mii_monitor [bonding]
[  982.465622] Call Trace:
[  982.468355]  dump_stack+0x8e/0xd0
[  982.472056]  __schedule_bug.cold.60+0x3a/0x60
[  982.476919]  __schedule+0x147b/0x1bc0
[  982.481007]  ? firmware_map_remove+0x16b/0x16b
[  982.485967]  ? hrtimer_fixup_init+0x40/0x40
[  982.490625]  schedule+0xd9/0x250
[  982.494227]  schedule_hrtimeout_range_clock+0x10d/0x2c0
[  982.500058]  ? hrtimer_nanosleep_restart+0x130/0x130
[  982.505598]  ? hrtimer_init_sleeper_on_stack+0x90/0x90
[  982.511332]  ? usleep_range+0x88/0x130
[  982.515514]  ? recalibrate_cpu_khz+0x10/0x10
[  982.520279]  ? ktime_get+0xab/0x1c0
[  982.524175]  ? usleep_range+0x88/0x130
[  982.528355]  usleep_range+0xdd/0x130
[  982.532344]  ? console_conditional_schedule+0x30/0x30
[  982.537987]  ? igc_put_hw_semaphore+0x17/0x60 [igc]
[  982.543432]  igc_read_phy_reg_gpy+0x111/0x2b0 [igc]
[  982.548887]  igc_phy_has_link+0xfa/0x260 [igc]
[  982.553847]  ? igc_get_phy_id+0x210/0x210 [igc]
[  982.558894]  ? lock_acquire+0x34d/0x890
[  982.563187]  ? lock_downgrade+0x710/0x710
[  982.567659]  ? rcu_read_unlock+0x50/0x50

45 more lines

diff --git a/drivers/net/ethernet/intel/igc/igc_phy.c b/drivers/net/ethernet/intel/igc/igc_phy.c
index 40dbf4b43234..6961f65d36b9 100644
--- a/drivers/net/ethernet/intel/igc/igc_phy.c
+++ b/drivers/net/ethernet/intel/igc/igc_phy.c

@@ -581,7 +581,7 @@ static s32 igc_read_phy_reg_mdic(struct igc_hw *hw, u32 offset, u16 *data)
 	 * the lower time out
 	 */
 	for (i = 0; i < IGC_GEN_POLL_TIMEOUT; i++) {
-		usleep_range(500, 1000);
+		udelay(50);
 		mdic = rd32(IGC_MDIC);
 		if (mdic & IGC_MDIC_READY)
 			break;

@@ -638,7 +638,7 @@ static s32 igc_write_phy_reg_mdic(struct igc_hw *hw, u32 offset, u16 data)
 	 * the lower time out
 	 */
 	for (i = 0; i < IGC_GEN_POLL_TIMEOUT; i++) {
-		usleep_range(500, 1000);
+		udelay(50);
 		mdic = rd32(IGC_MDIC);
 		if (mdic & IGC_MDIC_READY)
 			break;

-- 
2.31.1

From: Sasha Neftin <redacted>

An infinite loop may occur if we fail to acquire the HW semaphore,
which is needed for resource release.
This will typically happen if the hardware is surprise-removed.
At this stage there is nothing to do, except log an error and quit.

Fixes: c0071c7aa5fe ("igc: Add HW initialization code")
Suggested-by: Dima Ruinskiy <redacted>
Signed-off-by: Sasha Neftin <redacted>
Tested-by: Naama Meir <redacted>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
---
 drivers/net/ethernet/intel/igc/igc_i225.c | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/intel/igc/igc_i225.c b/drivers/net/ethernet/intel/igc/igc_i225.c
index 66ea566488d1..59d5c467ea6e 100644
--- a/drivers/net/ethernet/intel/igc/igc_i225.c
+++ b/drivers/net/ethernet/intel/igc/igc_i225.c

@@ -156,8 +156,15 @@ void igc_release_swfw_sync_i225(struct igc_hw *hw, u16 mask)
 {
 	u32 swfw_sync;
 
-	while (igc_get_hw_semaphore_i225(hw))
-		; /* Empty */
+	/* Releasing the resource requires first getting the HW semaphore.
+	 * If we fail to get the semaphore, there is nothing we can do,
+	 * except log an error and quit. We are not allowed to hang here
+	 * indefinitely, as it may cause denial of service or system crash.
+	 */
+	if (igc_get_hw_semaphore_i225(hw)) {
+		hw_dbg("Failed to release SW_FW_SYNC.\n");
+		return;
+	}
 
 	swfw_sync = rd32(IGC_SW_FW_SYNC);
 	swfw_sync &= ~mask;

-- 
2.31.1

From: Vinicius Costa Gomes <vinicius.gomes@intel.com>

Some mainboard/CPU combinations, in particular, Alder Lake-S with a
W680 mainboard, have shown problems (system hangs usually, no kernel
logs) with suspend/resume when PCIe PTM is enabled and active. In some
cases, it could be reproduced when removing the igc module.

The best we can do is to stop PTM dialogs from the downstream/device
side before the interface is brought down. PCIe PTM will be re-enabled
when the interface is being brought up.

Fixes: a90ec8483732 ("igc: Add support for PTP getcrosststamp()")
Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Tested-by: Naama Meir <redacted>
Acked-by: Paul Menzel <redacted>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
---
 drivers/net/ethernet/intel/igc/igc_ptp.c | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/intel/igc/igc_ptp.c b/drivers/net/ethernet/intel/igc/igc_ptp.c
index 0d6e3215e98f..653e9f1e35b5 100644
--- a/drivers/net/ethernet/intel/igc/igc_ptp.c
+++ b/drivers/net/ethernet/intel/igc/igc_ptp.c

@@ -992,6 +992,17 @@ static void igc_ptp_time_restore(struct igc_adapter *adapter)
 	igc_ptp_write_i225(adapter, &ts);
 }
 
+static void igc_ptm_stop(struct igc_adapter *adapter)
+{
+	struct igc_hw *hw = &adapter->hw;
+	u32 ctrl;
+
+	ctrl = rd32(IGC_PTM_CTRL);
+	ctrl &= ~IGC_PTM_CTRL_EN;
+
+	wr32(IGC_PTM_CTRL, ctrl);
+}
+
 /**
  * igc_ptp_suspend - Disable PTP work items and prepare for suspend
  * @adapter: Board private structure

@@ -1009,8 +1020,10 @@ void igc_ptp_suspend(struct igc_adapter *adapter)
 	adapter->ptp_tx_skb = NULL;
 	clear_bit_unlock(__IGC_PTP_TX_IN_PROGRESS, &adapter->state);
 
-	if (pci_device_is_present(adapter->pdev))
+	if (pci_device_is_present(adapter->pdev)) {
 		igc_ptp_time_save(adapter);
+		igc_ptm_stop(adapter);
+	}
 }
 
 /**

-- 
2.31.1

Hello:

This series was applied to netdev/net.git (master)
by Tony Nguyen [off-list ref]:

On Wed, 13 Apr 2022 10:08:10 -0700 you wrote:

This series contains updates to igc and e1000e drivers.

Sasha removes waiting for hardware semaphore as it could cause an
infinite loop and changes usleep_range() calls done under atomic
context to udelay() for igc. For e1000e, he changes some variables from
u16 to u32 to prevent possible overflow of values.

[...]

Here is the summary with links:
  - [net,1/4] igc: Fix infinite loop in release_swfw_sync
    https://git.kernel.org/netdev/net/c/907862e9aef7
  - [net,2/4] igc: Fix BUG: scheduling while atomic
    https://git.kernel.org/netdev/net/c/c80a29f0fe9b
  - [net,3/4] igc: Fix suspending when PTM is active
    https://git.kernel.org/netdev/net/c/822f52e7efdc
  - [net,4/4] e1000e: Fix possible overflow in LTR decoding
    https://git.kernel.org/netdev/net/c/04ebaa1cfdda

You are awesome, thank you!
-- 
Deet-doot-dot, I am a bot.
https://korg.docs.kernel.org/patchwork/pwbot.html