| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-ID: <8F4C390AFA9F4444A4AA77F4A3BEC78A190E7843@HASMSX110.ger.corp.intel.com>
Date: Wed, 27 Jul 2016 14:09:13 +0000
From: "Avargil, Raanan" <raanan.avargil@...el.com>
To: Jarod Wilson <jarod@...hat.com>,
"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
"Hall, Christopher S" <christopher.s.hall@...el.com>
CC: "netdev@...r.kernel.org" <netdev@...r.kernel.org>,
"intel-wired-lan@...ts.osuosl.org" <intel-wired-lan@...ts.osuosl.org>
Subject: RE: [Intel-wired-lan] [PATCH net-next v3 1/2] e1000e: factor out
systim sanitization
This is prepatory work for an expanding list of adapter families that have occasional ~10 hour clock jumps when being used for PTP. Factor out the sanitization function and convert to using a feature (bug) flag, per suggestion from Jesse Brandeburg.
Littering functional code with device-specific checks is much messier than simply checking a flag, and having device-specific init set flags as needed.
There are probably a number of other cases in the e1000e code that could/should be converted similarly.
Suggested-by: Jesse Brandeburg <jesse.brandeburg@...el.com>
CC: Jesse Brandeburg <jesse.brandeburg@...el.com>
CC: Jeff Kirsher <jeffrey.t.kirsher@...el.com>
CC: intel-wired-lan@...ts.osuosl.org
CC: netdev@...r.kernel.org
Signed-off-by: Jarod Wilson <jarod@...hat.com>
---
drivers/net/ethernet/intel/e1000e/82571.c | 6 ++- drivers/net/ethernet/intel/e1000e/e1000.h | 1 + drivers/net/ethernet/intel/e1000e/netdev.c | 66 ++++++++++++++++++------------
3 files changed, 44 insertions(+), 29 deletions(-)
diff --git a/drivers/net/ethernet/intel/e1000e/82571.c b/drivers/net/ethernet/intel/e1000e/82571.c
index 7fd4d54..6b03c85 100644
--- a/drivers/net/ethernet/intel/e1000e/82571.c
+++ b/drivers/net/ethernet/intel/e1000e/82571.c
@@ -2032,7 +2032,8 @@ const struct e1000_info e1000_82574_info = {
| FLAG2_DISABLE_ASPM_L0S
| FLAG2_DISABLE_ASPM_L1
| FLAG2_NO_DISABLE_RX
- | FLAG2_DMA_BURST,
+ | FLAG2_DMA_BURST
+ | FLAG2_CHECK_SYSTIM_OVERFLOW,
.pba = 32,
.max_hw_frame_size = DEFAULT_JUMBO,
.get_variants = e1000_get_variants_82571,
@@ -2053,7 +2054,8 @@ const struct e1000_info e1000_82583_info = {
| FLAG_HAS_CTRLEXT_ON_LOAD,
.flags2 = FLAG2_DISABLE_ASPM_L0S
| FLAG2_DISABLE_ASPM_L1
- | FLAG2_NO_DISABLE_RX,
+ | FLAG2_NO_DISABLE_RX
+ | FLAG2_CHECK_SYSTIM_OVERFLOW,
.pba = 32,
.max_hw_frame_size = DEFAULT_JUMBO,
.get_variants = e1000_get_variants_82571,
diff --git a/drivers/net/ethernet/intel/e1000e/e1000.h b/drivers/net/ethernet/intel/e1000e/e1000.h
index ef96cd1..879cca4 100644
--- a/drivers/net/ethernet/intel/e1000e/e1000.h
+++ b/drivers/net/ethernet/intel/e1000e/e1000.h
@@ -452,6 +452,7 @@ s32 e1000e_get_base_timinca(struct e1000_adapter *adapter, u32 *timinca);
#define FLAG2_PCIM2PCI_ARBITER_WA BIT(11)
#define FLAG2_DFLT_CRC_STRIPPING BIT(12)
#define FLAG2_CHECK_RX_HWTSTAMP BIT(13)
+#define FLAG2_CHECK_SYSTIM_OVERFLOW BIT(14)
#define E1000_RX_DESC_PS(R, i) \
(&(((union e1000_rx_desc_packet_split *)((R).desc))[i])) diff --git a/drivers/net/ethernet/intel/e1000e/netdev.c b/drivers/net/ethernet/intel/e1000e/netdev.c
index 41f32c0..1b2df11 100644
--- a/drivers/net/ethernet/intel/e1000e/netdev.c
+++ b/drivers/net/ethernet/intel/e1000e/netdev.c
@@ -4303,6 +4303,42 @@ void e1000e_reinit_locked(struct e1000_adapter *adapter) }
/**
+ * e1000e_sanitize_systim - sanitize raw cycle counter reads
+ * @hw: pointer to the HW structure
+ * @systim: cycle_t value read, sanitized and returned
+ *
+ * Errata for 82574/82583 possible bad bits read from SYSTIMH/L:
+ * check to see that the time is incrementing at a reasonable
+ * rate and is a multiple of incvalue.
+ **/
+static cycle_t e1000e_sanitize_systim(struct e1000_hw *hw, cycle_t
+systim) {
+ u64 time_delta, rem, temp;
+ cycle_t systim_next;
+ u32 incvalue;
+ int i;
+
+ incvalue = er32(TIMINCA) & E1000_TIMINCA_INCVALUE_MASK;
+ for (i = 0; i < E1000_MAX_82574_SYSTIM_REREADS; i++) {
+ /* latch SYSTIMH on read of SYSTIML */
+ systim_next = (cycle_t)er32(SYSTIML);
+ systim_next |= (cycle_t)er32(SYSTIMH) << 32;
+
+ time_delta = systim_next - systim;
+ temp = time_delta;
+ /* VMWare users have seen incvalue of zero, don't div / 0 */
+ rem = incvalue ? do_div(temp, incvalue) : (time_delta != 0);
+
+ systim = systim_next;
+
+ if ((time_delta < E1000_82574_SYSTIM_EPSILON) && (rem == 0))
+ break;
+ }
+
+ return systim;
+}
+
+/**
* e1000e_cyclecounter_read - read raw cycle counter (used by time counter)
* @cc: cyclecounter structure
**/
@@ -4312,7 +4348,7 @@ static cycle_t e1000e_cyclecounter_read(const struct cyclecounter *cc)
cc);
struct e1000_hw *hw = &adapter->hw;
u32 systimel, systimeh;
- cycle_t systim, systim_next;
+ cycle_t systim;
/* SYSTIMH latching upon SYSTIML read does not work well.
* This means that if SYSTIML overflows after we read it but before
* we read SYSTIMH, the value of SYSTIMH has been incremented and we @@ -4335,33 +4371,9 @@ static cycle_t e1000e_cyclecounter_read(const struct cyclecounter *cc)
systim = (cycle_t)systimel;
systim |= (cycle_t)systimeh << 32;
- if ((hw->mac.type == e1000_82574) || (hw->mac.type == e1000_82583)) {
- u64 time_delta, rem, temp;
- u32 incvalue;
- int i;
-
- /* errata for 82574/82583 possible bad bits read from SYSTIMH/L
- * check to see that the time is incrementing at a reasonable
- * rate and is a multiple of incvalue
- */
- incvalue = er32(TIMINCA) & E1000_TIMINCA_INCVALUE_MASK;
- for (i = 0; i < E1000_MAX_82574_SYSTIM_REREADS; i++) {
- /* latch SYSTIMH on read of SYSTIML */
- systim_next = (cycle_t)er32(SYSTIML);
- systim_next |= (cycle_t)er32(SYSTIMH) << 32;
-
- time_delta = systim_next - systim;
- temp = time_delta;
- /* VMWare users have seen incvalue of zero, don't div / 0 */
- rem = incvalue ? do_div(temp, incvalue) : (time_delta != 0);
-
- systim = systim_next;
+ if (adapter->flags2 & FLAG2_CHECK_SYSTIM_OVERFLOW)
+ systim = e1000e_sanitize_systim(hw, systim);
- if ((time_delta < E1000_82574_SYSTIM_EPSILON) &&
- (rem == 0))
- break;
- }
- }
return systim;
}
--
1.8.3.1
_______________________________________________
Intel-wired-lan mailing list
Intel-wired-lan@...ts.osuosl.org
http://lists.osuosl.org/mailman/listinfo/intel-wired-lan
Looks ok to me.
Adding Chris who asked what happens if we reach the max retry counter (E1000_MAX_82574_SYSTIM_REREAD)?
This counter is set to 50.
Can you, for testing purposes, decreased this value (or even set it to 0) and see what happens?
---------------------------------------------------------------------
Intel Israel (74) Limited
This e-mail and any attachments may contain confidential material for
the sole use of the intended recipient(s). Any review or distribution
by others is strictly prohibited. If you are not the intended
recipient, please contact the sender and delete all copies.
Powered by blists - more mailing lists