[PATCH] mm: trigger panic on bad page or PTE states if panic_on_oops

[Christian Borntraeger <borntraeger@de.ibm.com>]

while debugging a memory management problem it helped a lot to
get a system dump as early as possible for bad page states.

Lets assume that if panic_on_oops is set then the system should
not continue with broken mm data structures.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
 mm/memory.c     | 2 ++
 mm/page_alloc.c | 2 ++
 2 files changed, 4 insertions(+)

diff --git a/mm/memory.c b/mm/memory.c
index 2c3536c..bdbf9cc 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -696,6 +696,8 @@ static void print_bad_pte(struct vm_area_struct *vma, unsigned long addr,
 		printk(KERN_ALERT "vma->vm_file->f_op->mmap: %pSR\n",
 		       vma->vm_file->f_op->mmap);
 	dump_stack();
+	if (panic_on_oops)
+		panic("Fatal exception");
 	add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE);
 }
 
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 8e20f9c..8c19db3 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -337,6 +337,8 @@ static void bad_page(struct page *page, const char *reason,
 
 	print_modules();
 	dump_stack();
+	if (panic_on_oops)
+		panic("Fatal exception");
 out:
 	/* Leave bad fields for debug, except PageBuddy could make trouble */
 	page_mapcount_reset(page); /* remove PageBuddy */
-- 
2.3.0

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