On Thu, Dec 26, 2013 at 10:20:52PM -0500, Sasha Levin wrote: > Most of the VM_BUG_ON assertions are performed on a page. Usually, when > one of these assertions fails we'll get a BUG_ON with a call stack and > the registers. > > I've recently noticed based on the requests to add a small piece of code > that dumps the page to various VM_BUG_ON sites that the page dump is quite > useful to people debugging issues in mm. > > This patch adds a VM_BUG_ON_PAGE(cond, page) which beyond doing what > VM_BUG_ON() does, also dumps the page before executing the actual BUG_ON. > > Signed-off-by: Sasha Levin <sasha.levin@xxxxxxxxxx> I like the idea. One thing I've noticed you have a lot of page flag based asserts, like: VM_BUG_ON_PAGE(PageLRU(page), page); VM_BUG_ON_PAGE(!PageLocked(page), page); What about adding per-page-flag assert macros, like: PageNotLRU_assert(page); PageLocked_assert(page); ? This way we will always dump right page on bug. -- Kirill A. Shutemov -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>