From: Kuppuswamy Sathyanarayanan sathyanarayanan.kuppuswamy@linux.intel.com
stable inclusion from stable-v5.10.121 commit 40d428b528c59dda1ba6377dbf387e2ff1c7f8ea category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I5L6CQ
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...
--------------------------------
[ Upstream commit 203926da2bff8e172200a2f11c758987af112d4a ]
When a Root Port or Root Complex Event Collector receives an error Message e.g., ERR_COR, it sets PCI_ERR_ROOT_COR_RCV in the Root Error Status register and logs the Requester ID in the Error Source Identification register. If it receives a second ERR_COR Message before software clears PCI_ERR_ROOT_COR_RCV, hardware sets PCI_ERR_ROOT_MULTI_COR_RCV and the Requester ID is lost.
In the following scenario, PCI_ERR_ROOT_MULTI_COR_RCV was never cleared:
- hardware receives ERR_COR message - hardware sets PCI_ERR_ROOT_COR_RCV - aer_irq() entered - aer_irq(): status = pci_read_config_dword(PCI_ERR_ROOT_STATUS) - aer_irq(): now status == PCI_ERR_ROOT_COR_RCV - hardware receives second ERR_COR message - hardware sets PCI_ERR_ROOT_MULTI_COR_RCV - aer_irq(): pci_write_config_dword(PCI_ERR_ROOT_STATUS, status) - PCI_ERR_ROOT_COR_RCV is cleared; PCI_ERR_ROOT_MULTI_COR_RCV is set - aer_irq() entered again - aer_irq(): status = pci_read_config_dword(PCI_ERR_ROOT_STATUS) - aer_irq(): now status == PCI_ERR_ROOT_MULTI_COR_RCV - aer_irq() exits because PCI_ERR_ROOT_COR_RCV not set - PCI_ERR_ROOT_MULTI_COR_RCV is still set
The same problem occurred with ERR_NONFATAL/ERR_FATAL Messages and PCI_ERR_ROOT_UNCOR_RCV and PCI_ERR_ROOT_MULTI_UNCOR_RCV.
Fix the problem by queueing an AER event and clearing the Root Error Status bits when any of these bits are set:
PCI_ERR_ROOT_COR_RCV PCI_ERR_ROOT_UNCOR_RCV PCI_ERR_ROOT_MULTI_COR_RCV PCI_ERR_ROOT_MULTI_UNCOR_RCV
See the bugzilla link for details from Eric about how to reproduce this problem.
[bhelgaas: commit log, move repro details to bugzilla] Fixes: e167bfcaa4cd ("PCI: aerdrv: remove magical ROOT_ERR_STATUS_MASKS") Link: https://bugzilla.kernel.org/show_bug.cgi?id=215992 Link: https://lore.kernel.org/r/20220418150237.1021519-1-sathyanarayanan.kuppuswam... Reported-by: Eric Badger ebadger@purestorage.com Signed-off-by: Kuppuswamy Sathyanarayanan sathyanarayanan.kuppuswamy@linux.intel.com Signed-off-by: Bjorn Helgaas bhelgaas@google.com Reviewed-by: Ashok Raj ashok.raj@intel.com Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com Acked-by: Xie XiuQi xiexiuqi@huawei.com --- drivers/pci/pcie/aer.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/drivers/pci/pcie/aer.c b/drivers/pci/pcie/aer.c index 77b0f2c45bc0..09b96d2e4ee7 100644 --- a/drivers/pci/pcie/aer.c +++ b/drivers/pci/pcie/aer.c @@ -101,6 +101,11 @@ struct aer_stats { #define ERR_COR_ID(d) (d & 0xffff) #define ERR_UNCOR_ID(d) (d >> 16)
+#define AER_ERR_STATUS_MASK (PCI_ERR_ROOT_UNCOR_RCV | \ + PCI_ERR_ROOT_COR_RCV | \ + PCI_ERR_ROOT_MULTI_COR_RCV | \ + PCI_ERR_ROOT_MULTI_UNCOR_RCV) + static int pcie_aer_disable; static pci_ers_result_t aer_root_reset(struct pci_dev *dev);
@@ -1194,7 +1199,7 @@ static irqreturn_t aer_irq(int irq, void *context) struct aer_err_source e_src = {};
pci_read_config_dword(rp, aer + PCI_ERR_ROOT_STATUS, &e_src.status); - if (!(e_src.status & (PCI_ERR_ROOT_UNCOR_RCV|PCI_ERR_ROOT_COR_RCV))) + if (!(e_src.status & AER_ERR_STATUS_MASK)) return IRQ_NONE;
pci_read_config_dword(rp, aer + PCI_ERR_ROOT_ERR_SRC, &e_src.id);