This is a note to let you know that I've just added the patch titled
bnx2x: Improve reliability in case of nested PCI errors
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
bnx2x-improve-reliability-in-case-of-nested-pci-errors.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From foo@baz Wed Feb 28 16:19:30 CET 2018
From: "Guilherme G. Piccoli" <gpiccoli@xxxxxxxxxxxxxxxxxx>
Date: Fri, 22 Dec 2017 13:01:39 -0200
Subject: bnx2x: Improve reliability in case of nested PCI errors
From: "Guilherme G. Piccoli" <gpiccoli@xxxxxxxxxxxxxxxxxx>
[ Upstream commit f7084059a9cb9e56a186e1677b1dcffd76c2cd24 ]
While in recovery process of PCI error (called EEH on PowerPC arch),
another PCI transaction could be corrupted causing a situation of
nested PCI errors. Also, this scenario could be reproduced with
error injection mechanisms (for debug purposes).
We observe that in case of nested PCI errors, bnx2x might attempt to
initialize its shmem and cause a kernel crash due to bad addresses
read from MCP. Multiple different stack traces were observed depending
on the point the second PCI error happens.
This patch avoids the crashes by:
* failing PCI recovery in case of nested errors (since multiple
PCI errors in a row are not expected to lead to a functional
adapter anyway), and by,
* preventing access to adapter FW when MCP is failed (we mark it as
failed when shmem cannot get initialized properly).
Reported-by: Abdul Haleem <abdhalee@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Guilherme G. Piccoli <gpiccoli@xxxxxxxxxxxxxxxxxx>
Acked-by: Shahed Shaikh <Shahed.Shaikh@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c | 4 ++--
drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c | 14 +++++++++++++-
2 files changed, 15 insertions(+), 3 deletions(-)
--- a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c
+++ b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c
@@ -3052,7 +3052,7 @@ int bnx2x_nic_unload(struct bnx2x *bp, i
del_timer_sync(&bp->timer);
- if (IS_PF(bp)) {
+ if (IS_PF(bp) && !BP_NOMCP(bp)) {
/* Set ALWAYS_ALIVE bit in shmem */
bp->fw_drv_pulse_wr_seq |= DRV_PULSE_ALWAYS_ALIVE;
bnx2x_drv_pulse(bp);
@@ -3134,7 +3134,7 @@ int bnx2x_nic_unload(struct bnx2x *bp, i
bp->cnic_loaded = false;
/* Clear driver version indication in shmem */
- if (IS_PF(bp))
+ if (IS_PF(bp) && !BP_NOMCP(bp))
bnx2x_update_mng_version(bp);
/* Check if there are pending parity attentions. If there are - set
--- a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c
+++ b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c
@@ -9570,6 +9570,15 @@ static int bnx2x_init_shmem(struct bnx2x
do {
bp->common.shmem_base = REG_RD(bp, MISC_REG_SHARED_MEM_ADDR);
+
+ /* If we read all 0xFFs, means we are in PCI error state and
+ * should bail out to avoid crashes on adapter's FW reads.
+ */
+ if (bp->common.shmem_base == 0xFFFFFFFF) {
+ bp->flags |= NO_MCP_FLAG;
+ return -ENODEV;
+ }
+
if (bp->common.shmem_base) {
val = SHMEM_RD(bp, validity_map[BP_PORT(bp)]);
if (val & SHR_MEM_VALIDITY_MB)
@@ -14214,7 +14223,10 @@ static pci_ers_result_t bnx2x_io_slot_re
BNX2X_ERR("IO slot reset --> driver unload\n");
/* MCP should have been reset; Need to wait for validity */
- bnx2x_init_shmem(bp);
+ if (bnx2x_init_shmem(bp)) {
+ rtnl_unlock();
+ return PCI_ERS_RESULT_DISCONNECT;
+ }
if (IS_PF(bp) && SHMEM2_HAS(bp, drv_capabilities_flag)) {
u32 v;
Patches currently in stable-queue which might be from gpiccoli@xxxxxxxxxxxxxxxxxx are
queue-4.4/bnx2x-improve-reliability-in-case-of-nested-pci-errors.patch