lkml.org 
[lkml]   [2020]   [Nov]   [2]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v4 1/1] PCI/ERR: don't clobber status after reset_link()
Date
Commit 6d2c89441571 ("PCI/ERR: Update error status after reset_link()")
broke pcie_do_recovery(): updating status after reset_link() has the ill
side effect of causing recovery to fail if the error status is
PCI_ERS_RESULT_CAN_RECOVER or PCI_ERS_RESULT_NEED_RESET as the following
code will *never* run in the case of a successful reset_link()

177 if (status == PCI_ERS_RESULT_CAN_RECOVER) {
...
181 }

183 if (status == PCI_ERS_RESULT_NEED_RESET) {
...
192 }

For instance in the case of PCI_ERS_RESULT_NEED_RESET we end up not
calling ->slot_reset() (because we skip report_slot_reset()) thus
breaking driver (re)initialisation.

Don't clobber status with the return value of reset_link(); set status
to PCI_ERS_RESULT_RECOVERED, in case of successful link reset, if and
only if the initial value of error status is PCI_ERS_RESULT_DISCONNECT
or PCI_ERS_RESULT_NO_AER_DRIVER.

Fixes: 6d2c89441571 ("PCI/ERR: Update error status after reset_link()")
Signed-off-by: Hedi Berriche <hedi.berriche@hpe.com>

Reviewed-by: Sinan Kaya <okaya@kernel.org>
Cc: Russ Anderson <rja@hpe.com>
Cc: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Joerg Roedel <jroedel@suse.com>

Cc: stable@kernel.org # v5.7+
---
drivers/pci/pcie/err.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/pci/pcie/err.c b/drivers/pci/pcie/err.c
index c543f419d8f9..2730826cfd8a 100644
--- a/drivers/pci/pcie/err.c
+++ b/drivers/pci/pcie/err.c
@@ -165,10 +165,13 @@ pci_ers_result_t pcie_do_recovery(struct pci_dev *dev,
pci_dbg(dev, "broadcast error_detected message\n");
if (state == pci_channel_io_frozen) {
pci_walk_bus(bus, report_frozen_detected, &status);
- status = reset_link(dev);
- if (status != PCI_ERS_RESULT_RECOVERED) {
+ if (reset_link(dev) != PCI_ERS_RESULT_RECOVERED) {
pci_warn(dev, "link reset failed\n");
goto failed;
+ } else {
+ if (status == PCI_ERS_RESULT_DISCONNECT ||
+ status == PCI_ERS_RESULT_NO_AER_DRIVER)
+ status = PCI_ERS_RESULT_RECOVERED;
}
} else {
pci_walk_bus(bus, report_normal_detected, &status);
--
2.28.0
\
 
 \ /
  Last update: 2020-11-02 16:10    [W:0.088 / U:0.148 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site