We get this stack when the rp doesn't power up in resume noirq:
dump_backtrace.cfi_jt+0x0/0x4
dump_stack_lvl+0xb4/0x10c
show_regs_before_dump_stack+0x1c/0x30
arm64_serror_panic+0x110/0x1a8
do_serror+0x16c/0x1cc
el1_error+0x8c/0x10c
do_raw_spin_unlock+0x74/0xdc
pci_bus_read_config_word+0xdc/0x1dc
pci_restore_msi_state+0x2f4/0x36c
pci_restore_state+0x13f0/0x1444
pci_pm_resume_noirq+0x158/0x318
dpm_run_callback+0x178/0x5e8
device_resume_noirq+0x250/0x264
async_resume_noirq+0x20/0xf8
async_run_entry_fn+0xfc/0x364
process_one_work+0x37c/0x7f4
worker_thread+0x3e8/0x754
kthread+0x168/0x204
ret_from_fork+0x10/0x18
The ep device uses msix, the restore process will write bar space
in __pci_msix_desc_mask_irq, which will result in accessing the
powerdown area when the rp doesn't power on.
It makes sense we should do nothing when the device is still powerdown.
Signed-off-by: Jianrong Zhang <zhangjianrong5@xxxxxxxxxx>
Signed-off-by: Jiantao Zhang <water.zhangjiantao@xxxxxxxxxx>
---
drivers/pci/pci.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index fba95486caaf..279f6e8c5a00 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -1764,7 +1764,7 @@ static void pci_restore_rebar_state(struct pci_dev *pdev)
*/
void pci_restore_state(struct pci_dev *dev)
{
- if (!dev->state_saved)
+ if (!dev->state_saved || dev->current_state == PCI_UNKNOWN)
return;
/*
--
2.17.1
