The patch titled Subject: mm: change nr_ptes BUG_ON to WARN_ON has been added to the -mm tree. Its filename is mm-change-nr_ptes-bug_on-to-warn_on.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Hugh Dickins <hughd@xxxxxxxxxx> Subject: mm: change nr_ptes BUG_ON to WARN_ON Occasionally an isolated BUG_ON(mm->nr_ptes) gets reported, indicating that not all the page tables allocated could be found and freed when exit_mmap() tore down the user address space. There's usually nothing we can say about it, beyond that it's probably a sign of some bad memory or memory corruption; though it might still indicate a bug in vma or page table management (and did recently reveal a race in THP, fixed a few months ago). But one overdue change we can make is from BUG_ON to WARN_ON. It's fairly likely that the system will crash shortly afterwards in some other way (for example, the BUG_ON(page_mapped(page)) in __delete_from_page_cache(), once an inode mapped into the lost page tables gets evicted); but might tell us more before that. Change the BUG_ON(page_mapped) to WARN_ON too? Later perhaps: I'm less eager, since that one has several times led to fixes. Signed-off-by: Hugh Dickins <hughd@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/mmap.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff -puN mm/mmap.c~mm-change-nr_ptes-bug_on-to-warn_on mm/mmap.c --- a/mm/mmap.c~mm-change-nr_ptes-bug_on-to-warn_on +++ a/mm/mmap.c @@ -2309,7 +2309,7 @@ void exit_mmap(struct mm_struct *mm) } vm_unacct_memory(nr_accounted); - BUG_ON(mm->nr_ptes > (FIRST_USER_ADDRESS+PMD_SIZE-1)>>PMD_SHIFT); + WARN_ON(mm->nr_ptes > (FIRST_USER_ADDRESS+PMD_SIZE-1)>>PMD_SHIFT); } /* Insert vm structure into process list sorted by address _ Patches currently in -mm which might be from hughd@xxxxxxxxxx are origin.patch mm-change-nr_ptes-bug_on-to-warn_on.patch prio_tree-debugging-patch.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html