[PATCH AUTOSEL 4.19 079/191] PCI/AER: Take reference on error devices

From: Sasha Levin
Date: Sat Nov 09 2019 - 21:42:52 EST


From: Keith Busch <keith.busch@xxxxxxxxx>

[ Upstream commit 60271ab044a53edb9dcbe76bebea2221c4ff04d9 ]

Error handling may be running in parallel with a hot removal. Reference
count the device during AER handling so the device can not be freed while
AER wants to reference it.

Signed-off-by: Keith Busch <keith.busch@xxxxxxxxx>
Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
Reviewed-by: Sinan Kaya <okaya@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/pci/pcie/aer.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/pci/pcie/aer.c b/drivers/pci/pcie/aer.c
index 637d638f73da5..ffbbd759683c5 100644
--- a/drivers/pci/pcie/aer.c
+++ b/drivers/pci/pcie/aer.c
@@ -866,7 +866,7 @@ void cper_print_aer(struct pci_dev *dev, int aer_severity,
static int add_error_device(struct aer_err_info *e_info, struct pci_dev *dev)
{
if (e_info->error_dev_num < AER_MAX_MULTI_ERR_DEVICES) {
- e_info->dev[e_info->error_dev_num] = dev;
+ e_info->dev[e_info->error_dev_num] = pci_dev_get(dev);
e_info->error_dev_num++;
return 0;
}
@@ -1013,6 +1013,7 @@ static void handle_error_source(struct pci_dev *dev, struct aer_err_info *info)
pcie_do_nonfatal_recovery(dev);
else if (info->severity == AER_FATAL)
pcie_do_fatal_recovery(dev, PCIE_PORT_SERVICE_AER);
+ pci_dev_put(dev);
}

#ifdef CONFIG_ACPI_APEI_PCIEAER
--
2.20.1