powerpc/eeh: Use safe list traversal when walking EEH devices

Currently, we're trasversing the EEH devices list using list_for_each_entry().
That's not safe enough because the EEH devices might be removed from
its parent PE while doing iteration. The patch replaces that with
list_for_each_entry_safe().

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

3 files changed, 9 insertions, 9 deletions

diff --git a/arch/powerpc/include/asm/eeh.h b/arch/powerpc/include/asm/eeh.h
index 2ce22d7b71a0..e8c411b63caf 100644
--- a/arch/powerpc/include/asm/eeh.h
+++ b/arch/powerpc/include/asm/eeh.h
@@ -74,8 +74,8 @@ struct eeh_pe {
         struct list_head child;         /* Child PEs                    */
 };
 
-#define eeh_pe_for_each_dev(pe, edev) \
-                list_for_each_entry(edev, &pe->edevs, list)
+#define eeh_pe_for_each_dev(pe, edev, tmp) \
+                list_for_each_entry_safe(edev, tmp, &pe->edevs, list)
 
 /*
  * The struct is used to trace EEH state for the associated
diff --git a/arch/powerpc/kernel/eeh.c b/arch/powerpc/kernel/eeh.c
index ce81477316be..56bd4584f61f 100644
--- a/arch/powerpc/kernel/eeh.c
+++ b/arch/powerpc/kernel/eeh.c
@@ -231,7 +231,7 @@ static size_t eeh_gather_pci_data(struct eeh_dev *edev, char * buf, size_t len)
 void eeh_slot_error_detail(struct eeh_pe *pe, int severity)
 {
         size_t loglen = 0;
-        struct eeh_dev *edev;
+        struct eeh_dev *edev, *tmp;
         bool valid_cfg_log = true;
 
         /*
@@ -251,7 +251,7 @@ void eeh_slot_error_detail(struct eeh_pe *pe, int severity)
                 eeh_pe_restore_bars(pe);
 
                 pci_regs_buf[0] = 0;
-                eeh_pe_for_each_dev(pe, edev) {
+                eeh_pe_for_each_dev(pe, edev, tmp) {
                         loglen += eeh_gather_pci_data(edev, pci_regs_buf + loglen,
                                                       EEH_PCI_REGS_LOG_LEN - loglen);
                 }
diff --git a/arch/powerpc/kernel/eeh_pe.c b/arch/powerpc/kernel/eeh_pe.c
index 32ef40940bad..c8b815e45c8f 100644
--- a/arch/powerpc/kernel/eeh_pe.c
+++ b/arch/powerpc/kernel/eeh_pe.c
@@ -176,7 +176,7 @@ void *eeh_pe_dev_traverse(struct eeh_pe *root,
                 eeh_traverse_func fn, void *flag)
 {
         struct eeh_pe *pe;
-        struct eeh_dev *edev;
+        struct eeh_dev *edev, *tmp;
         void *ret;
 
         if (!root) {
@@ -186,7 +186,7 @@ void *eeh_pe_dev_traverse(struct eeh_pe *root,
 
         /* Traverse root PE */
         for (pe = root; pe; pe = eeh_pe_next(pe, root)) {
-                eeh_pe_for_each_dev(pe, edev) {
+                eeh_pe_for_each_dev(pe, edev, tmp) {
                         ret = fn(edev, flag);
                         if (ret)
                                 return ret;
@@ -501,7 +501,7 @@ static void *__eeh_pe_state_mark(void *data, void *flag)
 {
         struct eeh_pe *pe = (struct eeh_pe *)data;
         int state = *((int *)flag);
-        struct eeh_dev *tmp;
+        struct eeh_dev *edev, *tmp;
         struct pci_dev *pdev;
 
         /*
@@ -511,8 +511,8 @@ static void *__eeh_pe_state_mark(void *data, void *flag)
          * the PCI device driver.
          */
         pe->state |= state;
-        eeh_pe_for_each_dev(pe, tmp) {
-                pdev = eeh_dev_to_pci_dev(tmp);
+        eeh_pe_for_each_dev(pe, edev, tmp) {
+                pdev = eeh_dev_to_pci_dev(edev);
                 if (pdev)
                         pdev->error_state = pci_channel_io_frozen;
         }